GB1563542A - Copy production machines - Google Patents

Abstract

In printing operation with automatic control, the copying machine can make copies on the basis of image information which originates from one of a number of connected image sources which are equipped with optical and/or electronic image-scanning devices. The image sources are called in serially as soon as a current job has been dealt with. The printing operation can be interrupted at any time if, in copying operation, copies, usually in small numbers, are to be made. The copying operation can, however, not be interrupted by printing jobs which arise.

Description

(54) COPY PRODUCTION MACHINES (71) We, INTERNATIONAL BUSINESS MACHINES CORPORATION, a Corporation organized and existing under the laws of the State of New York in the United States of America, of Armonk, New York 10504, United States of America do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to copy production machines.

Ever since Guttenberg's invention of the printing press, man has continually improved and modified the processes and machines for producing image bearing copies. Today, a wide variety of copy production machines exist for producing copies under varying conditions and at diverse speeds. Many of the copy production machines are of the so-called convenience copier class, wherein a relatively small number of copies are made from a given original. Other copy production machines produce a greater number of copies per original image through varying copy production processes, such as offset printing, transfer electrographic techniques, thermal techniques, no-contact printing, such as by ink jets, and impact printing.

Since the advent of power typing and utilization of magnetic memory tapes, cards, as well as optical systems, a set of diverse techniques for word processing has evolved. A main thrust to word processing is to relieve the typist from repetitive typing, in the same manner that copy production machines have relieved man from manual copy production. Both of such systems are commonly used independently in business and other types of offices. The functions have been treated as independent office functions. It is believed that such independent usage may not optimumly use the capabilities of these apparatus.

According to the invention, there is provided a copy production machine comprising a copy generator system for producing copies from original documents or from input digital data signals and including a control system for controlling the machine automatically to produce copy runs of one or more copies from an original document or from each of a series of original documents, fed to the machine, said control system being responsive to digital data control signals to cause interruptions in a run of copies from input digital data signals and to control the machine to produce copies from an original document or from each of a series of original documents during said interruptions.

In order that the invention can be fully understood, a preferred embodiment thereof will now be described with reference to the accompanying drawings, in which: Figure 1 is a block diagram of a system in which the present invention may be advantageously employed.

Figure IA is a block diagram of control circuits interpreting the present invention.

Figure I B is a diagrammatic showing of a machine incorporating the present invention and controlled by the Figure 1A illustrated control circuits.

Figure 2 is a block diagram of a multiprocessor machine controller used in the Figure 1A control circuits.

Figures 3A and 3B are schematic block diagrams of interconnections between a controlling digital computer and a controlled unit asconnected for use in the Figure 2 illustrated controller respectively for SCP 60 and CMC 61.

Figure 4 is a block diagram showing a digital computer used in the Figure 2 illustrated controller.

Figures 5 and 6 are shots showing the instruction execution of the pipelined processors.

Figure 7 is a diagram showing interprocess address space in the memory of CMC 61.

Figure 8 is a simplified diagrammatic showing of MPC 65 and bus select circuit 76 bus connections and control.

Figure 9 is a flow chart illustrating a noninterrupted flow of a background print job and automatic revision to the foreground copy mode.

Figure 10 is a flow chart detailing a job termination portion of the Figure 10 flow chart.

Figure 11 is a flow chart showing copy selection interrupt of an active print mode.

Figure 12 is a flow chart showing copy selection interrupt of an active print mode in simplex and duplex copy printing operations showing sheet and set copy interrupt synchronization points.

Figure 13 is a diagram showing circuits for AND logic of print mode interrupt by a copy selection for maintaining print mode print copy count.

Figure 14 is a diagram of circuits for AND logic of alternating image sources in the print mode.

Referring now more particularly to the drawings, like numerals indicate like parts and features in the various diagrams. Figure 1 shows communication and copy production network employs machines constructed using the present invention. Location A is physically remote from location B. Each location A and B has a copy production machine 10A and 10B, respectively, constructed in accordance with the present invention. Further, each location A and B include a word processing system 16A, 16B, respectively, copier mode input 12A1, 12by, respectively, and data processing systems 1 8A and 18B, respectively. The various illustrated units are interconnected by the copy production machine which includes word processing capabilities, data processing capabilities in addition to copy production capabilities.The machines 10A and 10B can intercommunicate for transferring image indicating signals such that signals originating in machine 10A can result in copies produced in machine 10B. Similarly, copy production machines 10A, 10B, also provide computer output from either of the illustrated data processing systems 18A, 18B. Machines also can receive word processing indicating signals from systems 16A, 16B, as well as supplying word processing indicating signals to such systems. The copier mode inputs 12A, 12B, create images from original documents for the production of copies by the machines 10A, 10B, respectively. Scanners may be employed to transmit original documents using either digital or slow-scan video (analog) techniques.Accordingly, in practicing the present invention in the manufacture of copy production machines, such machines can be advantageously employed in complex image transferring communication networks as will become more readily apparent.

Figures IA and 1B respectively show a copy production machine 10 constructed using the principles of the present invention and which may be advantageously employed in the Figure 1 illustrated image communication network. The copy production machine centers around a copy production portion CPP 13. CPP 13 is illustrated as a transfer electrographic copy production portion, no limitation thereto intended. A plurality of image inputs are provided to CPP 13.

Such inputs selectively denominated by numeral 12 include a document scanning optical input in optical communication with a semiautomatic document feed SADF 11. SADF 11 includes a document glass on which an original document may be placed either manually by lifting a SADF lid (not shown) or via semiautomatic document feed from input tray (not shown). The optical image from SADF 11 is transmitted to CPP 13 using known optical techniques commonly found in convenience copiers of several types. Additionally, original input optics 12 include a laser input LI which receives word processing indicating signals for creating an optical image as an image input to CPP 13 via common input 23. The original input optics 12 include a SADF control OIC 12A as well as a laser input control 12B.

The laser input can receive signals from a local terminal LT 16 which is a word processing terminal for receiving word processing signal bearing magnetic cards at input slot 137 and for ejecting such cards at output slot 137A. Signals from LT 16 are temporarily stored in nonvolatile store NVS 19. Additionally, for communication in an image communication network as shown in Figure 1, a remote terminal connector RTC 17 provides signal communication to various remote units, collectively denominated by numeral 18. In Figures 1A and 1B, numeral 18 indicates the remainder of the network as shown in Figure 1. The word processing signals from LT 16 or RTC 17 are initially stored in memory 64.From memory 64 (Fig. 2) multiprocessor machine controller MPMC 15 effects transfer of the signals to LIC 12B for generating an image to be transferred to CPP 13, as will become more readily apparent as well as to NVS 19. In producing a first set, signals from memory 64 actuate LIC 12B. In second and higher numbered sets, signals stored in NVS 19 go to memory 64 for being supplied to LIC 12B for image generation. In one embodiment print jobs received by RTC 17 and LT 16 are alternated. A priority scheme could be employed if desired.

Copy production machine 10 includes a copy output portion 14 having a plurality of copy receiving units. When laser input LI 12 supplies images to CPP 13, the copies produced are directed toward output portion 14B as will beater more fully described. When SADF 11 is used as an input to optics 12, the copy production machine 10 is in what is termed a copy mode wherein the copies produced by CPP 13 are directed either to copy exit tray 14A, or to copy collator 14C. The output unit 14B in a constructed embodiment was reserved for copies produced in the print mode.

MPMC 15 controls all units in copy production machine 10. The various closely controlled units such as LIC 12B, NVS 19, RTC 17, and LT 16, are controlled by a pair of later described unidirectional busses collectively denominated by MIDI in Figure IA. The other units are those related to copy production and which are supervised by MPMC. Communication is by a bidirectional data bus IOC shown connected to the copier exit control CEC 15A, printer exit control PEC 15B, CPP 13, SADF control 12A. The interactions of the various units of copy production machine 10 will become apparent from a continued reading.

CPP 13 Before proceeding further with the description of the invention, the operation of CPP 13 is described as a preferred constructed embodiment employing xerographic transfer electrographic techniques. Photoconductor drum member 20 rotates in the direction of the arrow past a plurality of xerographic processing stations, the first station 21 which imposes either a positive or negative electrostatic charge on the surface of photoconductor member 20. It is preferred that this charge can be a uniform electrostatic charge over a uniform photoconductor surface. Such charging is done in the absence of light such that projected optical images, indicated by dash line arrow 23, alter the electrostatic charge on the photoconductor member in preparation for image developing and transferring.The projected optical image from original input optics 12 exposes the photoconductor surface in area 22. Light in the projected image electrically discharges the surface areas of photoconductor member 20 in accordance with lightness. With minimal light reflected from the dark or printed areas of an original document, for example, there is no corresponding electrical discharge. As a result, an electrostatic charge remains in those areas of the photoconductive surface of member 20 corresponding to the dark or printed areas of an original document in SADF 11 (semiautomatic document feed) or by the image created. This charge pattern is termed a "latent" image on the photoconductive surface. Interimage erase lamp 30E discharges photoconductor member 20 outside defined image areas.

The next xerographic station is developer 24 which receives toner (ink) from toner supply 25 for being deposited and retained on the photoconductive surface still having an electrical charge. The developer station receives the toner with an electrostatic charge of polarity opposite to that of the charged areas of the photoconductive surface. Accordingly, the toner particles adhere electrostatically to the charged areas, but do not adhere to the discharged areas. Hence, the photoconductive surface, after leaving station 24, has a toned image corresponding to the dark and light areas of an original document in SADF 11 or of the image supplied by LI laser input.

Next, the latent image is transferred to copy paper in transfer station 26. The paper is brought to the station 26 from an input paper path portion 27 via synchronizing input gate 28. In station 26, the copy paper is charged and brought into contact with the toned image on the photoconductive surface which will result in a transfer of the toner to the copy paper. After such transfer, the sheet of image bearing copy paper is stripped from the photoconductive surface for transport along path 29. Next, the paper has the electrostatically carried image fused thereon in fusing station 31 for creating a permanent image on the copy paper. The copy paper receives electrostatic charges in station 26 which can have an adverse effect on copy handling. Accordingly, the copy paper is electrically discharged at station 32 before transfer to output portion 14.

Returning now to the photoconductor member 20, after the image area on member 20 leaves transfer station 26, there is a certain amount of residual toner on the photoconductive surface. Accordingly, cleaner station 30 has a rotating cleaning brush (not shown) to remove the residual toner for cleaning the image area in preparation for receiving the next image projected by original input optics 12. The cycle then repeats by charging the just-cleaned image area by charging station 21.

The production of simplex copies or the first side of duplexing copies by portion 13 includes transferring a blank sheet of paper from blank paper supply 35, thence to transfer station 26, fuser 31, and, when in the simplex mode, directly to the output copy portion 14. Blank paper supply 35 has an empty sensing switch 36 which inhibits operation of portion 13 in a known manner whenever supply 35 is out of paper.

When in the duplex mode, duplex diversion gate 42 is actuated by the duplex controlling circuits (not shown) to the upward position for deflecting single-image copies to travel over path 43 to the interim storage unit 40. These duplex controlling circuits (not shown) are actuated by MPMC 15. Here, the partially produced duplex copies (image on one side only) reside waiting for the next subsequent single-image run in which the copies receive the second image. Such copies residing in interim storage unit 40 is an intermediate copy production state.

In the next successive single-image run, initiated by inserting a document into SADF 11 or via MPMC 15, the copies are removed one at a time from the interim storage unit 40, transported over path 44, thence to path 27 for receiving a second image, as previously described. The two-image duplex copies are then transferred into output copy portion 14. Switch 41 of interim storage unit 40 detects whether or not there are any copies or paper in interim storage unit 40. If so, an intermediate copy production state signal is supplied over line 45 to later described control circuits.

The copy production machine has a control panel 52 having a plurality of lights and switches (most not shown) and connected to MPMC 15 for operating the entire machine 10 synchronously with respect to the movement of the image areas of photoconductor member 20. Billing meter M counts images processed for billing purposes. For example, paper release gate 28 is actuated synchronously with the image areas moving past developer station 24. Such controls are well known in the art and are not described here for purposes of brevity.

MPMC 15 The mulitprocessor machine controller MPMC 15 is shown in block diagram form in Figure 2. MPMC 15 includes a production machine controlling subsystem SCP 60 and a copy production machine controlling subsystem CMC 61. SCP 60 includes a system microprocessor SMP 62 which executes a set of control programs contained in control store 63 (either ROS or RAM or a combination of both), and uses page memory 64 as a main or working store. SMP 62 communicates with the other units in SCP 60 as well as peripheral units as later discussed, via a set of three unidirectional data transfer busses. The bus DI transfers data signals from the other units to SMP 62. In a preferred constructed embodiment, DI was eight bits wide (one character) plus parity, while signals emanating from SMP 62 were carried over bus MI to all of the other units.Address signals selecting which units are to send or receive signals with respect to SMP 62, as well as the other units are provided by SMP 62 over 16 bit wide address bus ADS. The above-described bus interconnedtions also provide signal communication between SCP 60 and the nonvolatile store 19, laser input 12B, local terminal LT 16, remote terminal connector RTC 17, and to CMC 61 via multiprocessor connector MPC 65.

CMC 61 is constructed similarly to SCP 60. It includes a copy microprocessor CMP 170 plus a control store 171 containing programs for operating CPP 13, a working store 172 for use as a main memory, and input/output registers 173, 174.

Signal communication between these units is via a bidirectional 8 bit data bus I/O under addressing control from CMP 70 via 16 bit address bus ADC. CMP 170 supplies address signals over bus ADC for selecting the source and destination of signals with respect to CMP 170. Such selection includes an address to multiprocessor connector MPC 65. I/O bus is preferably a character wide (8 bits) while ADC is preferbly two characters wide or 16 bits. CMC 61 via MDC 65 appears as an I/O device to the SCP 60 in the same manner as units 19, 12B, 16, and 17 appears as I/O device. Processor intercommunication via MPC 65 requires a plurality of memory cycles in both SCP 60 and CMC 61. A clock 75 times SCP 60 and CMC 61 on a memory cycle synchronized basis. That is, page memory 64 and working store 172 have identical length memory cycles.The operation of the memories are in synchronism under control of a two phase clock, phase 1, phase 2, supplied over lines 76 to all units within MPMC 15. Timing connections are not shown for purposes of brevity. Additionally, clock 75 issues a series of S pulses, S1 through S5, for timing instruction execution of CMP 170 and SMP 62.

Additionally, it may be desired under program control, to logically interconnect the busses MI, DI and ADS for enabling signal transfers in later described desired paths. To achieve this result, bus select circuit 76 under SMP 62 control, provides communication between the various busses. For example, signals received from MPC 65 on bus MI can be transferred through bus select circuit 76 to bus DI for receipt of SMP 62. Other permutations on signal transfers via the busses can be easily envisioned.

Referring next to Figure 3A, the logical interconnections between SMP 62 with controlled units 6365 and so forth. All the signals on the busses and individual control lines go to all units with the ADS and GP signals selecting which controlled unit is to respond for either receiving data signals or supplying data signals, respectively. From MI or to DI, SMP 62 supplies addressing signals over bus ADS to all units. If the instruction supplied over bus GP indicates data is to be transferred from SMP 62, to a controlled unit, that is indicated on the VO line when a binary 1 indicates signals are to be transferred to the microprocessor over DI while a binary 0 indicates microprocessor SMP 62 supplies a signal over MI. Write line WRT indicates to page memory that signals are to be recorded in the memory.The ITP line, the signal ITP indicates interrupt in process; i.e., the microprocessor 62 programmed had been interrupted and is handling that interrupt. I is interrupt, SDL is received from system clock 75, and means data latch, as will be later explained with respect to Figure 4, the line SK means sliver-killer which is a control signal for eliminating extraneous signals commonly referred to as slivers. These so-called signals result in interaction between successively actuated bistable circuits termed latches. Other timing signals for coordinating operation of all of the units in the MPMC 15 are received from system clock 75. Additionally, power-on reset circuit POR activates system clock 75 to send out timing signals and control signals for resetting all of the units to a reference state as is well known in the computer arts.

In the CMC 61 the decoding circuits and logic circuits which respond to the above-described signals are those normally used in conjunction with interconnecting controlling and controlled units. Since such circuits and design principles are well known, further description of these details are dispensed with.

Referring next to Figure 3B, the logical interconnections between microprocessor 170 with controlled units 171-175 are shown. All of the signals on the busses and individual control lines to to all units with the ADC signals selecting which controlled unit 171-175 is to respond for either receiving data signals or supplying data signals, respectively, are bus IO. Control line I/O indicates whether CMP 170 is supplying or receiving signals in bus IO. When the I/O line has a binary I indicating signal data or instruction signals are to be transferred to the microprocessor 170 over IO while when it is a binary zero microprocessor 170 supplies data signals over IO. Write line WRT indicates to memory 172 that signals are to be recorded in the memory. The IIP line, the signal IIP indicates interrupt in process, i.e., the microprocessor 170 program has been interrupted and microprocessor 170 is handling that interrupt. I is interrupt, SDL (data latch) is received from system clock 176, and means data signals from IO are to be latched in microprocessor 170.The line SK means sliver-killer which is a control signal for eliminating extraneous signals commony referred to as slivers. These so-called signals result in interaction between successively actuated bistable circuits termed latches. Other timing signals for coordinating operation of all of the units 171-175 are received from system clock 176. Additionally, power on reset circuit POR activates system clock 75 to send out timing signals and control signals for resetting all of the units 170175 to a reference state as is well known in the computer arts.

The Microprocessors 62 and 170 Referring next to Figure 4, the data flow of the microprocessor 170 is detailed.

The data flow and operation of SMP 62 are identical. The sequence control circuits 180 are those logic circuits designed to implement the now to be described functions performable in the timing context of the following description. Such sequence control circuits SCC 180 include instruction decoders, memory latchers and the like, for sequencing the operation of the Figure 6 illustrated data-flow circuits, using a two-phase clock, l, 2 from clock 176. The processor contains an 8 bit wide (1 character wide) arithmetic and logic unit ALU 181. ALU 181 receives signals to be combined during a 2 and supplies static output signals over ALU output bus 182 during each phase 1.Operatively associated with ALU 181 is a 16 bit accumulator consisting of two registers, a low register ACL 183 which has its output connections over 8 bit wide bus 184 as one input to ALU 181. The second register of the accumulator is ACH register 185. When the microprocessor 170 operates with a two character wide or 2 byte wide word, the functions of ACL 183 and ACH 185 alternate. That is, in a first portion of the operation, which requires two complete microprocessor 170 cycles, as later described, ACL 183 contains the lower order 8 bits of a 16 bit wide word, while ACH 185 contains the upper 8 bits of the 16 bit wide word. ALU 181 first operates on the lower 8 bits recieved over ACL bus 184 and supplies the result signals over ALU output bus 182 to DB register 186.

During this same transferring action, ACH 185 is supplying the upper 8 bits through DO register 187, thence over DO bus 188 to ACL 183. During the next ALU cycle, the upper 8 bits are operated upon. In the preferred and constructed embodiment, ALU 181 operates with two's complement notation and can perform either 8 bit wide or 16 bit wide arithmetic as above described. Eight bit wide logic operations are also performed.

ALU 181 contains three indicating latches (not shown) which memorize the results of arithmetic and logical functions for use in later processor cycles, such as conditional jumps or branches, and so-called input carry instructions. These three indicators are low, equal (EQ), and carry. Utilization of these indicators will be better understood by continued reading of the specification. Processor sequence control circuits 180 can entertain a single level of interrupt and includes an internal interrupt mask register (not shown) for disabling interrupts as is well known in the computer arts. The low order bits of the address signals supplied to bus ADS by the ALH register 190 (high order bits of the address) and ALL register 191 (the loworder 8 bits of the address) are denominated as work registers. These registers are divided into 32 groups of 16, 2 byte wide, logical registers.A portion of ALL register 191 supplies GP signals for selecting which groups of registers are accessible by microprocessor 170.

As will be later detailed, microprocessor 170 requires two processor cycles for processing an I/O instruction. The first cycle is a set-up cycle while the second cycle is a data transfer cycle. When an I/O operation requires a transfer of a succession of bytes, then the first cycle sets up a unit 171-175 for transferring a plurality of bytes such that the I/O operation appears as a set-up cycle followed by a plurality of data transfer cycles. The microprocessor 170 is designed to operate with a plurality of relatively slow acting devices, i.e., copy production machine 10.

The time required for the microprocessor 170 to perform its functions is relatively small compared to the time required by the controlled devices. Accordingly, under clock 176 control, the microprocessor 170 can be effectively turned off to allow a controlled device to have exclusive use of the IO bus.

From examination of Figure 6, it can be seen that all of the registers, being latches, will maintain their respective signal states whenever the clock phases l and 2, are not supplied. Therefore, upon an interruption of the microprocessor 170 functioning by a controlled device 171-175, the signal state of the processor 170 enables it to begin operating again as if there had been no interruption.

The other registers in the microprocessor 170 are described with the instructions set for facilitating a better understanding of the interaction of these registers. The microprocessor employs instructions of variable length, 1, 2, or 3 bytes. The first byte of any instruction always includes the operation code, while succeeding bytes, numbered 2 or 3, contain address data or operand data, also referred to as immediate data.

The fastest instruction execution requires one microprocessor cycle while the longest instruction requires six processor cycles. An interrupt requires ten cycles to process. In all designations, bit 0 is the least significant bit.

Instruction Repertoire The instruction repertoire is described in groups of instructions, all of which have defined instruction word formats. The instructions are defined by the title, mnemonic, number of cycles required by the microprocessor to execute the instruction, number of operands (OP) and the number of bytes in the instruction word. Additionally, breakdown of the command structure of the first byte is given.

REGISTER ARITHMETIC Instruction Mnemonic Cycles OP Bytes Add AR 3 1 1 Subtract SR 3 1 1 Load LR 3 1 1 Store STR 3 1 1 Load/Decrement LRD 5 1 1 Load/Bump LRB 5 1 1 The instruction byte is divided into two portions. The most significant 4 bits indicate the instruction code while the lower 4 bits indicate a register within a group of 16 registers as the operand source. All operations are taken to the accumulator register. The Register Arithmetic is 2-byte wide arithmetic.

BYTE ARITHMETIC Instruction Mnemonic Cycles OP Bytes Add AB 3 1 2 Subtract SB 3 1 2 Load LB 3 1 2 Store STB 3 1 2 Compare CB 3 1 2 And NB 3 1 2 Or OB 3 1 2 Xor XB 3 1 2 The most significant 5 bits of byte one of the instruction indicate the instruction command while the lower-most 3 bits indicate one of 8 registers. The second byte indicates one of 256 bytes addresses in memory to be used in the arithmetic, i.e., a difference between the register arithmetic and the byte arithmetic is that a byte arithmetic obtains the operand from memory.

IMMEDIATE ARITHMETIC Instruction Mnemonic Cycles Op Bytes Add AI 2 1 2 Subtract SI 2 1 2 Load LI 2 1 2 Compare CI 2 1 2 And NI 2 1 2 Or OI 2 1 2 Xor XI 2 1 2 Group GI 2 3 2 The byte 1 format is the same as for byte arithmetic with the second byte being the operand data. In the last instruction, Group, GI, the immediate data selects the registers in the register group as will become apparent.

ACCUMULATOR ARITHMETIC Instruction Mnemonic Cycles OP Bytes Add 1 Al 2 0 1 Subtract 1 S1 2 0 1 Shift Left SHL 2 0 1 Shift Right SHR 2 0 1 Clear CLA 1 0 1 Transpose TRA 1 0 1 Input Carry IC 1 0 1 All 8 bits of byte 1 are used to denote the function to be performed. All operations are conducted within the accumulator. Transpose instruction, TRA, swaps the high and low order register content of accumulator registers I83 and 185.

INDIRECTS Instruction Mnemonic Cycles OP Bytes Store STN 4 1 1 Load LN 4 1 1 This is an indirect addressing set of instructions wherein the upper-most 5 bits indicate the function while the lower-most 3 bits signify which of 8 registers are to contain the address in memory to be accessed.

BIT CONTROL Instruction Mnemonic Cycles OP Bytes Test/Preserve TP 1 1 1 Test/Reset TR 1 1 1 The upper 5 bits of the instruction byte indicate the function while the lower 3 bits indicate what bit to be tested in the accumulator register.

INPUT/OUTPUT Instruction Mnemonic Cycles OP Bytes Input In 4 1 2 Output OUT 4 1 2 The two instructions use the first byte as a command and the second byte to address one of the 256 addresses on the busses, MI, DI, or IO.

BRANCHES Instruction Mnemonic Cycles OP Bytes JUMP J 3 1 1 JUMP NOT EQUAL JNE 3/1 1 1 JUMP EQUAL JE 3/1 1 BRANCH B 3 1 2 BRANCH NOT EQUAL BNE 3/2 1 2 BRANCH NOT LOW BNL 3/2 1 2 BRANCH EQUAL BE 3/2 1 2 BRANCH HIGH BH 3/2 1 2 BRANCH AND LINK BAL 6 2 3 RETURN RTN 5 1 INTERRUPT - 10 The first three JUMP instructions are the three most significant bits for indicating the function. A fourth bit for indicating JUMP on plus or minus and the four lower order bits for indicating the jump length. In one notation, the plus indication, the binary 0 while the minus indication is a binary 1.

In the branch instructions, except for the BRANCH AND LINK first most significant bits together with the lower two significant bits, indicate the functions.

The middle two bits indicate plus or minus 256 address positions or ignore. The BRANCH AND LINK, a 3 byte instruction, selects one of four registers with the lower 2 bits of the command first byte and uses the upper-most 6 bits as a function indicator. The two bytes are a 16 bit address for the address bus with the second byte being the 8 low significant bits and the third byte being the 8 more significant bits. The return instruction is merely a 1 byte instruction having the same format as the BRANCH AND LINK command byte. The interrupt is not an instruction, but a single signal received over interrupt line I.

ALU Condition Codes The table below indicates the condition code in the ALU low, equal (EQ), or carry set as a result of the executed class of instructions as set forth in the table below.

Instruction Class Low Equal (EQ) Carry Register Arithmetic 16th bit = 1 All bits (0-15) = 0 Carry from 16th bit Byte Arithmetic 8th bit = 1 All bits (0-7) = 0 Carry from 8th bit Bit Control All bits exclusive of Tested bit = 0 Unchanged bit being tested = 0 Shift Left All bits = 0 0 was shifted out of the 1 was shifted out of the 16th bit 16th bit Shift Right All bits = 0 0 was shifted out of the 1 was shifted out of the 1st bit 1st bit *Logical OR Results of OR Bits set by OR were Unchanged equals all ones all 0's **Logical AND Preserved bits are all Result of AND equals Unchanged ones all 0's Logical XOR Result all ones Result all zeroes Unchanged Input All bits exclusive 8th bit = 0 Unchanged of bits 8 = 0 (Data Input and Output) Input Carry Always Reset Carry = 0 Unchanged Compare Number compared is Number compared equals Carry from 8th bit greater than the byte the contents of the low of accumulator byte of accumulator *Test the set of bits (set by "OR") to be all 0's, and the result for all ones. Does TBS of individual bits. The set bits are indicated by ones in the mask (logical OR).

**Test the preserved bits to be all 0's, all ones, or mixed. The preserved bits are indicated by ones in the mask (logical AND).

A Jump instruction does not modify the accumulator 183,185 or indicator bits whether taken or not. The program counter has had one added to it since it addressed the jump instruction. The program counter 192 includes PCL register 192A and PCH register 192B, hereinafter referred to as counter 192. If taken, the low 4 bits of the instruction first byte replace the low 4 bits of the program counter 92 and the high 11 bits are modified if necessary. The range of the instruction address change is -15 to +17 bytes measured from the jump instruction address. If the destination is within this range, it is only necessary to specify the low 4 bits absolutely of the destination address and a bit to describe which direction (0 for +2 to +17 or 1 for -15 to +0: the +1 condition is not realizable).The +1 condition is not useful because the processor goes to +1 if the jump is not taken (therefore, if it was valid the processor would go to + 1 if the jump was taken or not).

In a branch instruction, the program counter 192 has been incremented to point to the second byte of the branch instruction word. The low 8 bits absolute of the destination program address are coded in the data byte (second byte). A code which describes how to modify the high 8 bits is coded into the instruction byte to: leave the high 8 bits the same, add one to the high 8 bits, or subtract one from the high 8 bits.

Branch on Equal and Branch on Not Equal test only the condition of the ALU 181 EQ indicator. Branch on Not Low tests only the condition of the Low indicator. Branch on High requires that both the EQ and Low indicators be off.

The BRANCH AND LINK instruction is an unconditional branch that specifies the 16 bit absolute branch address of the program destination and a 2 bit number indicating a register to be used. The address of the next executable instruction (following the BAL) is stored in the register specified by the 2 bit number.

Interrupt is not a programmable instruction but is executed whenever the Interrupt Request line F is activated by an external device and an Interrupt mask in STAT register 195 is equal to zero. Interrupt stops the execution of the program between instructions, reads the new status (register group, interrupt mask, EQ, LOW, CARRY) from the high byte of REGISTER 8, stores the old status in the low byte of REGISTER 8, stores the address of the next instruction to be performed in REGISTER 0, stores the accumulator in REGISTER 4 (without altering the accumulator), and branches to the address specified by the contents of REGISTER 12. The processor always specifies REGISTER GROUP 0 for interrupt. Interrupt requires ten processor cycles to complete. Register groups will be later described.

Return is an unconditional branch to a variable address and can be used in conjunction with the BRANCH AND LINK or to return to the main Program after having been interrupted. Two bytes are read from the register specified to define the absolute branch address. A return using register 8 of register group 8 is defined as a return from interrupt. In this case the new status (EQ, LOW, CARRY, interrupt mask and register group) is read from the low order byte of REGISTER 8.

Arithmetic Group instructions operate with the 16 bit accumulator 183,185 and 8 bit arithmetic-logic unit ALU 181 that are capable of performing various arithmetic and logical operations. Three condition indicators (LOW, EQ, CARRY) are set on the results of some operations. Two's complement 16 bit arithmetic is performed except for byte operations and some immediate operations which are two's complement 8 bit operations. The high order bit is the sign bit; negative numbers are indicated by a one in the sign bit position. Subtraction is accomplished by two's complement addition. Any arithmetic operation that results in a CARRY will set and CARRY latch even though the accumulator may not be changed.

Double Byte Arithmetic is performed with registers 0-15 of the current group for the Add, Subtract, Load and Store instructions. Load Register and Bump (add +1) uses registers 4-7 and registers 12-15. Load Register and Decrement uses registers 0--3 and registers 8-11. In the add register and subtract register instructions, AR, SR, the 16 bits of the addressed or specified register are added to or subtracted from the accumulator and the result is placed in the accumulator. EQ is set if the result is all zeroes. Low is set if the high order bit is a one.

Load Register instruction LR loads 16 bit signal contents of the specified register into the accumulator 183, 185. The contents of the addressed register are unchanged. The ALU 181 indicators are not altered. The Store Register instruction, STR, stores the 16 bit contents of the accumulator 183, 185 into the specified register. The contents of the accumulator 183, 185 and the ALU 181 indicators are not altered.

In the Load Register and Bump, LRB, and Load Register and Decrement, LRD instruction, an absolute one is added to or subtracted from the contents of the specified register, respectively. The result is placed in the accumulator 83, 85 and the specified register. The indicators are updated as for an add or subtract, AR, SR.

For the Byte Arithmetic instructions, bytes 0-511 of memory 64 are addressable by the Byte Arithmetic instructions. The directly addressable memory 172 is divided into sections: bytes 0-255 are addressable when register groups 0-7 are selected while bytes 256-511 are addressable when register groups 8-15 are selected. Bytes 512-767 and 768-1023 are two additional groups. This sectioning yields 32 register groups in memory from which the processor operates, In the instructions AB, SB, CB, LB and STB, the 8 bit contents of the specified byte are added to, subtracted from, compared with, loaded into, or stored from the accumulator register ACL 183, respectively.The high order byte of the accumulator in ACH register 185 is not disturbed. The ALU 181 condition indicators are set on the result of the single byte arithmetic; add, subtract, and compare. The results of all of the byte operations except compare CB and store STB are placed in the accumulator register 183. Store alters the specified byte in the active byte group. Compare is a subtract operation that does not alter the contents of the accumulator 183, 185. Byte arithmetic is 8 bit signed arithmetic.

In the byte NB, OB and XB instructions, the specified byte is logically ANDed, ORed, or EXCLUSIVE-ORed with the accumulator register 183 contents, respectively. The result is kept in the accumulator register 183. The EQ ALU 81 indicator is set: for the AND operation if the result of the AND equals all 0's; for the OR operation if the bits set by the OR were all 0's; for the EXCLUSIVE-OR operation if there is identity between the byte and accumulator (result = all 0's).

The LOW indicator is set: for the AND operation if the preserved bits are all l's; for the EXCLUSIVE-OR operation if the byte and accumulator are bit for bit opposites (result = all l's). The logical AND can test the mask selected to be all zeroes, all one or mixed. The mask selected bits are indicated by ones in the corresponding positions of the byte used as the mask. The logical AND tests the bits that are preserved, while the logical OR tests the bits that are then set to one. If only one bit is selected then the logical OR does a test bit and set.

The Immediate Arithmetic Instructions AI, SI, CI, LI, NI, OI and XI are the same as the byte operations except that eight bits of immediate data are used instead of the contents of an addressed byte and the Add and Subtract Operations are 16 bit signed arithmetic rather than 8 bit signed.

The Group Immediate Instruction GI takes 8 bits of immediate data to alter the contents of the status indicator register 195 to select register groups and enable or inhibit interrupt. LOW, EQ, and CARRY condition indicators in ALU 81 are not altered. The immediate data (byte two) is divided into five parts. BITS 0 are the new register group bits (new register group is coded in binary). BIT 5 is the command bit to put BITS 0--4 into the internal register group buffer if the command bit is a zero. BIT 7 is the new interrupt mask (a one masks out interrupts). BIT 6 is the command bit to put BIT 7 into the internal interrupt mask if the command bit is a zero.

The accumulator arithmetic instructions Al, S1, respectively add or subtract an absolute one to or from the contents of the accumulator 183, 185, and the result is left in the accumulator 183, 185. This is 16 bit signed arithmetic and the ALU 181 condition indicators are set on the result.

The accumulator instructions SHL and SHR shift the signal contents of the accumulator 183, 185 left or right one digit position or binary place, respectively.

For shift left, the high order bit is shifted into the CARRY latch (not shown) in ALU 181 and a zero is shifted into the low order bit except when the previous instruction was an input CARRY. After an input CARRY, the CARRY latch condition before the shift is shifted into the low order bit. For shift right, the lower order bit is shifted into the CARRY latch, and the state of the high order bit is maintained. When SHIFT RIGHT is preceded by input CARRY, the state of the CARRY latch before the shift is shifted into accumulator 183, 185 Bit 15. EQ condition indicator of ALU 181 is set if a 0 is shifted to the carry latch. LOW condition indicator of ALU 181 is set if the resulting contents of the accumulator 183, 185 is all 0's.

The accumulator instruction CLA clears the accumulator 183, 185 to all 0's.

Transpose TRA exchanges the low order register 183 with the high order byte register 185 signal contents. The ALU 181 indicators are unchanged.

The accumulator instruction IC transfers the signal state of signal contents of the CARRY latch to the low order bit of the arithmetic-logic unit 181 on the next following instruction if the next instruction is an add, subtract, bump, decrement, shift left, or compare operation. CARRY is inputted to Bit 15 on a shift right.

Interrupt is inhibited by this instruction until the next instruction is performed. The ALU 181 indicators Low is reset and EQ is set if the carry latch is a 0. If the input carry precedes any instruction other than the ones mentioned above it will have no effect on instruction execution. If the instruction following the input carry changes the ALU 181 condition indicators, then the indicator information from the input carry is destroyed.

The two Indirect Data Transfer instructions STN and LN can access registers 8-I 5. Load Indirectly instruction accesses the specified register and uses its contents as an address to fetch a byte of data and load it into the low eight bits (register 183) of the accumulator without disturbing the high 8 bits (register 185).

Store Indirectly accesses the specified register and uses its contents as an address to store the low eight bits of the accumulator register 183 into the specified byte. The ALU 181 indicators are not altered.

The Bit Test or control instructions TR and TP take specified bit of the low order byte of the accumulator register 183 for test. The ALU 181 condition indicator EQ is set if the bit is a 0. Concurrently, the bit is either reset or preserved in the accumulator respectively.

The Input/Output instruction, IN, OUT, respectively transfer data to the accumulator register 183 from an VO device (CPP 13 for example) and from the accumulator to an I/O device (CPP 13 for example). These instructions are two cycle operations. The first cycle puts the modified device code on the data out lines, the second cycle is the actual data transfer cycle; the low eight bits of the accumulator in register 183 are outputted to data in lines, and the device code is outputted on the address lines ADC. An OUT instruction does not change the ALU 181 indicators. On an IN instruction, EQ is set if the high order bit of the data inputted is a . LOW is always reset. The Input/Output instructions can specify 256 devices each'for data transfer.Generally, an VO device will require more than one device address to specify different types of operations such as READ and TEST STATUS, etc.

A Power On Reset POR initialization places the processor in the following state: Accumulator = Register Group = Interrupt Mask = 1 LOW, EQ CARRY = X (unknown) The microprocessor 170 will begin operation by reading memory location 65,533.

Microprocessor Instruction Execution The processor 170 is pipelined to allow the memory 172 a full processor cycle for access time. To do this, the microprocessor 170 requests a read from memory several cycles ahead of when it needs a data byte. Several restrictions are maintained throughout the instruction set.

1. Each instruction must fetch the same number of bytes as it uses.

2. Each instruction must leave the microprocessor with the next instruction in the INSTRUCTION BUFFER, IB register 196.

3. At "Phase Two Time" at the beginning of Sequence Two, as later described, the TEMPORARY BUFFER (TB) 197 must contain the byte following the current instruction. (Note that this byte was fetched by the previous instruction).

4. Each instruction decodes "TERM" (Terminate) as later described, which resets the instruction sequence counter (not shown) in clock 176 for CMP 176 and a separate sequence clock (not shown) for CMP 170 to Sequence one, allows the next fetch to be done from the IB 196 and loads the next instruction into IR 198.

5. At "Phase Two Time" at the beginning of instruction Sequence Two the low accumulator register 183 and the high accumulator register 185 must contain the appropriate signals. (Note that the previous instruction may have had other data in these registers during its execution.) Microprocessor 170 is built exclusively of latch logic. 2 signals are the output of latches (or static decodes using the output of latches) that are strobed (sampled or transferred by a clock signal called a strobe) at 2 time. l sighals are the outputs of latches (or static decodes using the outputs of latches) that are strobed at l time. l signals are used as the inputs to 2 latches and 2 signals are used as the inputs to l latches.

The fetch decodes (memory references) are done from the IB register 196 at SEQUENCE 1 (SEQ 1), because the IR register 198 is loaded at l, SEQ 1 (FIGURES 7 & 8). At sequences, other than SEQ 1, the fetch decode is done from IR register 198. The fetch decodes are 2 signals, and therefore are strobed at C1.

The output of the fetch decodes are strobed into registers ALL 191, ALH 190, OL 200 and SCC 180. The Program counter 192 is updated from registers AOL 201 and AOH 202 at a 2 time. The execution and designation decodes l decodes off the IR' 198. These decodes are strobed at 2 time into SCC 180 to set up the ALU 181 and DESTINATION strobes which occur at l time. The output signals of ALU 181 are strobed into DB 186, DO 187 or AOH 202 in accordance with the instruction being executed. Then ACL 183 and ACH 185 are updated at 2 so another ALU 181 cycle can begin. It takes three processor cycles from the start of a fetch decode to the time that the accumulator 183, 185 is updated.A pipelined configuration means that in some cases a processor can be executing three separate instructions at the same time, as is known in the computer arts.

Instruction Sequences An instruction sequence chart in FIGURES 5 and 6 is a convenient shorthand catalog of the internal operation of the processor 170 during each sequence of each instruction. It can be a very useful tool in understanding the processor's operation.

This glossary of terms provides the information necessary for proper interpretation of these charts.

General Information The processor 170 is pipelined. While it is executing one instruction, it reads the next two bytes from memory 172. The first byte is guaranteed in IB 196 at the beginning of SEQ 1 and is used during SEQ 1 to provide three SEQ 1 decodes in SCC 180. At 81, SEQ 1, IB e TR where it remains until the next l, SEQ 1. All remaining instruction decodes are done from IR 198.

The second byte is in TB 197 at the beginning of SEQ 2. This byte may contain immediate data for the current instruction or it may be a next instruction byte. If it is a next instruction byte, then the current instruction needs to read only one byte from memory to provide the required two bytes. This two byte read occurs for all one byte instructions.

All memory 172 access begin at 1. The memory data is guaranteed in the data latch register DL 205 via bus 10 for CMP 170 by 2, i.e., one and one-half instruction execution sequences later. In the table below the memory timings for all instructions are set out together with the register destination (dest) from data latch register 205.

MEMORY REFERENCE TIMING TABLE 1 2 3 INSTRUCTION START DEST START DEST START DEST LRARSR 1 TB 1 TB 3 TB LRELRD 1 ACL 2 ACL 3 TB STR I TB - - - - AISI 1 TB 2 TB - CI GPI LI XIOINI 1 TB 2 TB - CBABSB LBXBOB NB 1 TB 2 TB 3 TB MEMORY REFERENCE TIMING TABLE INSTRUCTION START 1 DEST START2 DEST START3 DEST STB I TB 3 TB - - AI SI SHL SHR 1 TB 2 TB TRA CLA ICTBPTBR 1 TB BAL 1 ACL 2 X 5 TB RTN I TB 2 ACL 3 TB 4 TB B## IJO 1 TB 2 TB 3 TB B IJO* 1 TB 2 TB INTERRUPT 1 TB 5 ACL 8 TB 9 TB 10 TB BLI 1 TB 2 ACL 3 TB 4 ACL BSI I TB 2 ACL 3 TB IN OUT 1 TB 3 ACL 4 TB *A bar over a jump or branch instruction indicates jump or branch was not taken.

Code Operation (Phase 2) Decode TB DL e TB, ACL unchanged None ACL DL z ACL, TB unchanged TACL* or ITAL X None. ACL and TB are unchanged. NOTB* or TBNS Data will be lost unless SDL on line 206 is inhibited by DMA active on line 207. AND circuit 208 blocks 2 from generating SDL signals on line 206.

DMA means direct memory access as by registers 173, 174.

If IR 198 still contains the current instruction byte, the decodes are static. If the decode is for the overlap cycle of SEQ 1 (with the next instruction byte in IR 198), the ALU 181 condition latches are set during the last sequences (3-5) of the current instruction execution. The designated register is decoded by SCC 180. This special case is shown on the instruction sequence charts, Figures 7 and 8, by the terms TBNS or ITAL in the ALU columns.

The operation of the processor 170 in each sequence is divided into two categories: Control Logic (CL) of SCC 180 and ALU and Destination (ALU). The position of these two blocks within the sequence, (i.e., left half or right half) has no meaning. Operations can occur at 1 or 2 in either category. l occurs in the middle of a sequence. The 2 is always a sequence boundary.

Control Logic Glossary This is a list of terms which appear in the control logic CL columns.

WRITE.-WRT Indicates that a write into memory is initiated at Phase 1 rather than a read. A read is the default condition and requires no decodes. The WRT output line (Figure 5) is active when WRT appears in the chart.

OUTPUT 1ST I/O - OUT 1IO Indicates that the first cycle I/O code is placed on the output lines IO at #1. Address lines AL9 and AL11 of ADC are driven by the decode IOC1. I/O line is active (Figure 5).

OUTPUT 2ND I/O - OUT 2IO Indicates that the second cycle I/O code is placed on the output lines IO to #1.

Address lines AL10 and ALI 1 of ADS are driven by IOC2. I/O line is active (Figure 5).

TB # IB At each #2, SEQ 1 of every instruction, the signal contents of TB register 197 are transferred to IB register 196. The signal contents represent the next successive instruction following the current instruction.

IB SET Same operation as TB # IB but the intent is to stop IB 196 from following TB 197 rather than save the contents of the TB 197. It is followed at the next #1 by IB SET TO "TRA".

IB SET TO "TRA" Indicates that the reset inputs (not shown) on the IB 196 latches (not shown) are driven at #1. CNT OR PORX drives an overlapping set on bits 0, 3 and 5 producing a "TRA" instruction code BAL, POR then execute a TRA to complete their respective operations.

(TERM) Indicates the end of the instruction. SEQ 1 begins at the doubled line 220 on the chart. The sequence counter (not shown S1-S6) in clock 176 is reset by the decode TERM*.

PCI Indicates a read from memory and a Program Counter Increment. This action is a default condition and no decodes are needed.

#1: PC + 1 # AC #2: AO # PC PCNI A "NO OP". Same as PCI except the PC 192 is not updated at 2. The next PCI reads the same location again as though the first read did not occur. It is used because the processor lines signify something every l and some instructions have no Read/Write or I/O requirements during SEQUENCE 1. SPC (Set PC) is inhibited for the jumps and branches, for the shift instructions, and for Al and Sl instructions.

IBL, IRL, IRH Indicates a memory access (read or write) to a register IR (IB) means the register is specified by the low four bits of IR (IB). IB must be used during SEQ 1. IR 198 is used during all other sequences. L means the access is to the low byte of the register, H specifies the high byte. The decode IRSL* (IR selected) controls the formation of the address at #1.

Operation Control IB (0-3) z AO (0-3) IBX (SEQ 1 only) IR (0-3) # AO (0-3) IRX (all other sequences) L=0, H=1 # AO (4) ILH GP (0-2) AO (5-7) RGX GP (3) e AO (8) R3 0AO z AO (9-14) TBIR TB Indicates a memory access using the contents of TB 197 as the address. The decode TBSL* (TB selected) controls the formation of the memory address at #1.

Operation Control TB (0-7) # AO (0-7) TBX GP (3) # AO (8) R3 0 # AO (9-14) TBIR IRL + 8 Same as IRL except 1 e AO (3). It is used only in the RTN instruction to read the new status from memory. A one is placed on AL (3).

CAL HIGH BITS, TB e AOL Indicates a memory access to a location being branched to. The decodes TBSL* and AOSL* control address formation at Phase 1. The high bits are calculated by the counter logic CL for PCH + 1 and PCH and by the ALU for PCH - 1.

Phase 1: Operation Control TB (0-7) # AO (0-7) TBX PCH + 1 # AO (8-14) AOSL* = 1, BNF = 1 PCH # AO (8-14) AOSL* = 1, BNF = 0 PCH -1# AO (8-14) AOSL* = 0 Phase 2: AO # PC CAL HIGH BITS, IR AOL Similar to TB z AOL above except only the low four bits of the IR are used, and bits 4 through 7 are calculated by the counter logic. The decodes IRSL* and AOSL* control address formation by driving other control lines.

Phase 1: Operation Control IR (0-3) # AO (0-3) IRX CL (4-7) # AO (47) None (default) PCH + 1 # AO (8-14) AOSL* = 1, JF8 = 1 PCH # AO (8-14) AOSL* = 1, JF8 = 0 PCH - 1 # AO (8-14) AOSL* = 0 Phase 2: AO e PC OL, OH, 4L, 4H, 8L, 8H, 12L, 12H Indicates a memory access to a register directly specified by the control SCC 180.

Occurs only during interrupt. L indicates the low byte, H indicates the high byte.

Phase 1: Operation Control Register # AO (0-3) CN2, CN3 L=0,H= I eAO(4) ILH 0 # AO (5-13) TBIR 1 # AO (14) R9 Update PC, ACL # AOH, TB z AOL Indicates a memory 172 access to an address specified by the contents of TB and ACL. The address is also placed in PC 192 at 2. The address formation is controlled by AOTB* which drives other control lines. ACL 182 go through ALU 181.

Phase 1: Operation Control TB (0-7) # AO (0-7) TBX ACL (0-6) # AO (8-14) SAO Phase 2: AO z PC ACL # AOH, TB # AOL Same as above except PC 92 is not updated at Phase 2.

Destination (Dest) Glossary Items with boxes around them (e.g., ACL to DO # ACL) do not always occur.

On Branch or Jump taken the boxed destination occurs only when PCH 192B must be decremented to produce the proper address. The decrement occurs always, it just isn't loaded when it isn't needed. On all other instructions the boxed destination occurs if the instruction is also boxed.

Items in parenthesis are "don't care" conditions which occur but are not part of the desired operation.

There are seven standard data transfers: Phase 1 Phase 2 Decodes 1. ALU # DO - None (Default) 2. ALUDO DOACL BF3 3. ALU # DB - DBDS* ACH # DO - 4. ALU # DB DB # ACH BF2 ACH # DO DO # ACL 5. ALU # AOH - AOTB* TB # AOL DB # ACH ACH # DO DO # ACL 6. PCL # DO - PCSL.PSX 7. STATUS # DO - STSL.PSX Any variations of these are decoded separately as exceptions.

MISCELLANEOUS OPERATIONS Update Status The new status (REG GROUP, EQ, CARRY, LOW, INT MASK) which has been read from memory replaces the old status.

Operation Decode (Phase I) TB # STATUS UPST*, CHST, CHST* (Phase 2) Clear ACL and ACH ACL 182 and ACH 185 are reset to zero by driving the reset inputs of the register latches (not shown).

(Phase 1) (Phase 2) 0 - > ACL, 0 - > ACH CLAC Processor Forced to Execute TRA The IB 196 has been reset to a TRA instruction. The sequence counter (not showp) in clock 176 is reset to SEQ 1 and the processor executes the TRA before the next instruction from memory.

Interrupt is prevented from occurring until after the TRA is completed.

AC7* < EQ The EQ indicator is set by AC7* (used by VO instruction), the bit 7 of ACL 183.

IC SETS IC The Input Carry instruction sets the IC latch (not shown) in ALU 81.

"32" < DO DO z DO (5). Part of POR code.

ALU GLOSSARY This is a list of terms which appear in the ALU category.

X ALU NO - OP. No ALU decodes are provided. ALU 181 output at 182 defaults to all l's.

ACL + TB ALU 181 output is either ACL plus TB 197 or ACL 183 minus TB 197 depending on whether instruction was an ADD or a SUBTRACT.

ACL x TB ALU output is some logical combination of ACL and TB which is dependent on the actual instruction.

ACL ALU output is ACL.

TB ALU output is TB.

(MODIF) ALU output is modified in some manner depending on the instruction. Example: On an IN or OUT instruction TB -, DO except for bits 5 and 6 which are modified to reflect 0 and OUT respectively. ALU output is shown as TB (MODIF).

ACL INCR/DECR ALU output is ACL plus I or ACL minus 1 depending on the instruction.

PCH - ALU output is PCH minus 1.

PCH - I + CR Same as PCH - I except carry is added.

TBNS, ITAL ALU NO - OP. The destination of data signals entering the processor at the end of SEQUENCE 1 via register 105 must be specified by the previous instruction (although that instruction is no longer in the machine). To accomplish this action, two sets of latches are necessary. The ALU latches are used as the first set. The ALU latches drive the second set, TBNS and ITAL.

ITAL specifies the ACL as the destination. TBNS specifies no destination. The default condition (no decodes) specifies the TB as the destination.

CMP WORKING STORE 172 ADDRESSING Either SMP 62 or CMP 170 can access working store 172 as well as input and output registers 173, 174. SMP 62 accesses the registers and working store 172, 173, 174 via MPC 65 as will be later described. As shown in the Figure 7, the 16 bit address for bus ADC, is not completely used for accessing the registers in store 172 or the input/output registers 173, 174. Bit 12 of the CMP address space selects whether working store 172 or registers 173, 174 are accessed. When bit 12 is a binary I then registers 173, 174 are selected, as represented by the VO address space from addresses 4K to 8K. When bit 12 is a zero then the working store 172 address space from zero to 4K are selected. The lesser significant 12 bits select the address space within the two sections, using known address decoding techniques.

For the I/O address space, bits 3 through 11 select which VO semiconductive chips constituting the input and output registers 173, 174 are selected, while bits zero through 2 select bit positions within the chips forming the registers 73, 74 as will be later described. For working store 172, bits zero through 11 are a continuim of address space.

SMP 62 addressing accesses working store 172 and registers 173, 174 in two segments. With 8 byte group fetching for each access, i.e., the SMP 62 command to MPC 65 minimum access is for 8 bytes of signals in CMC 61. The first segment corresponds to address space of working store 172 while the second segment corresponds to the address space for registers 173, 174. Selection of the first and second segments as well as the byte groups will be better understood from a reading of description of MPC 65. In the address space bits zero to 7 of the ADS address bus from SMP 62 is used for controlling MPC 65. The upper four bits are a device select while the lower four bits are a command select which selects the segment and groups for initializing MPC 65 for data transfer; i.e., the address space shown in Figure 7 for SMP 62 is for the first byte of a two-byte command, as will become apparent.

Bus Controls MPC 65 and bus select circuit 76 are both shown in Figure 8. Bus select circuit 76 includes decoder 104 responding to signals from SMP 62 via control lines 103.

Decoder 104 output signals in turn control a pair of AO circuits 105, 106 for selectively interconnecting the byte wide busses MI and DI as well as connecting page memory 64 to DI via AO 106 and memory output line 102. With these connections, SMP 62 completely controls the bus interconnections and hence the data flow in MPMC 15 under microcode or software control. The lines 103 include CWRT which when active indicates that SMP 62 is supplying signals to be written either in page memory 64 input/output, etc. Line POR signifies that hardware circuits (not shown) are initiating a power on reset and that the bus connections are to be set for initializing MPMC for operation. In general, POR control causes a write into page memory 64 from MI as received from NVS 19.ADS 12 signal line signifies that the cycle of SMP 62 is in the address cycle; i.e., a memory address is being sent to page memory 64. DMACY indicates that DMA 64A has access to page memory 64. B1XCC, as well as 82DAM are timing cycles corresponding respectively to l and 2 phases of the system clock. Additional gating for generating these signals is not shown for brevity. CHNSW carries a signal defining the time that data on DI is valid during system clock 2. Lines INHDI and INHIO are special test control signals for testing the circuits and hence, are beyond scope of the present description.

Decoder 104 responds to the various lines 103 signals to actuate the AOs 105, 106 as described. The Al input portion of AO 105 connects DI to MI in that the other inputs to the Al input portion are DI and the output is directly connected to MI.

Similarly, A2 input portion of AO 105 interconnects DI to MI under DMA memory access control. Additionally, decoder 104 detects from SMP 62 control signals that it is all right to connect to DI.

AO 106 selectively connects IOX from MPC 65 to MI or the output of page memory 64 received over line 102 to MI. The Al input portion passes the IOX receive signal whenever the IO in line from decoder 104 is active and that DI is OK.

Further, the A2 input portion is activated when decoder 104 signifies it is not IO; i.e., it is a memory reference.

With regard to the above statements, page memory 64 is continuously cycled and AO 106 selectively degates it outputs from bus DI during input operations; i.e., when signals from IOX are to be transferred to MI.

MPC 65 is constructed using a similar design philosophy. Decode 110 responds to SMP 62 lines 103 signals as indicated in the drawing and to the ADS address signals to activate AND circuits 111 to pass signals from bus IO of CMC to cable IOX for gating by AO 106. Similarly, decode 112 responds to the SMP 62 control lines 103 signals to the ADS signals to activate AND circuits 113 to pass the signals of bus DI to IO bus of CMC. In general, MPC 65 operates in two phases. The first phase is the addressing phase; the second phase is the data transfer phase. The address of the memory in CMC which includes ROS control store 171, working store 172, plus registers 173, 174 is set forth in MPC register 114 at ADS 12 time from bus ADS. Additional control signals are supplied over DI.MPC register 114 supplies its output signals to bus ADC for addressing the above-mentioned modules in CMC. On the next and successive cycles data is transferred through AND circuits 113 from DI to IO bus as indicated by the addresses supplied to ADC from MPC register 114.

MPC register 114 includes a control bit (not shown) that inhibits CMP 170 by supplying an inhibit signal over line 114A. This inhibit signal makes memory space of CMC 61 available to SMP 62 for exercising complete control, obtaining information; performing diagnostics and program loading.

The Print Mode CPP 13 produces copies identically independent of the operational mode of the copy production machine 10, the mode difference being the selection of the image source being either SADF 11 or laser input LI 12B, with the output portions 14B or 14A, C, respectively. Before proceeding to print, SMP 62 determines whether the machine is in the copy mode or the print mode. The characteristics of these two modes are first described. In the copy mode, which is a foreground operational mode, i.e., the one most available to an operator of the machine, SADF 11 supplies optical images to CPP 13 for production of copies to be deposited in either exit tray 14A or to be collated in output portion 14C. A feature of the copy mode is that all collation is done in the output portion and that the input optics scan an original document to be reproduced.Such scanning can be by using the usual convenience copier optics, flying spot scanner, laser scanner, or any other form of scanning instrument. For example, the image on the document in SADF 11 may be scanned by a digitized scanner which converts the image into noncoded information (NCI) which then in turn operates laser input LI 12B for reproducing the document via area 22 of photoconductor drum 20. The other mode, the print mode, selects word processing or data processing inputs in the form of image indicating signals normally stored in non-volatile store NVS 19. These signals are buffered in page memory 64 and interpreted at the laser input to generate images in accordance with the signal indications to produce what is termed "print copies" for deposit in output portion 14B.Reverser REV may be used in conjunction with duplex copy production for use in connection with either 14B or 14C as is well known in the arts. A distinguishing feature of the print mode from the copy mode as embodied in copy production machine 10 is that all collation of the images being produced in the print mode is done before the images are processed by photoconductor drum 20. This mode of operation may be conveniently termed precollation. Precollation is performed by manipulating the image indicating signals received from data processing or word processing input in such a manner that the print copies exit from CPP 13 in a proper collated order. In this manner a single output at 14B receives fully collated copy sets in the print: mode.

From the above it is readily seen that in the copy mode there is a SADF 11 image source which shares the CPP 13 with other image sources yet has its own unique output portions 14A, C. In this manner, the copy mode and the print mode insofar as input and output are concerned are completely independent which facilitates sharing CPP 13 between the two modes of operation. Since the copy' mode is the foreground mode, i.e., the most convenient mode insofar as operators are concerned, during a power on reset (POR) copy production machine 10 is initially selected to be in a copy mode. This copy mode is inactive whenever no copies are actually being produced by CPP 13 or being transported to output ,portions 14A, C.When the copy mode is inactive, a request from a data Processor or a word processing station to print copies takes precedence bringing the background print mode into a foreground operating state. Initation of the print mode activity, taking it from a background state to a foreground operating state is described shortly. The background print mode can be maintained in the foreground operating state until the copy mode is selected or until the print mode becomes inactive whereat the copy production machine 10 automatically reverts to the foreground copy mode. In the print mode local terminal 16, nonvolatile store 19, and remote terminal connector 17 cooperate with MPMC 15 and LI 12B for producing print copies in CPP 13. A print mode request is initiated by an operator language called OCL (operator control language) which contains information enabling copy production machine 10 to produce a requested number of print copies in a predetermined format, also as defined by OCL. OCL language includes definitions of margins, font selection, tab stops, number of lines per page, and the like as is well known in the word processing industry. To initiate a word processing input, word processing recorded magnetic cards are inserted into local terminal 16 hopper 137 such as a unit built by International Business Machines Corporation, Armonk, New York, and identified as a Magnetic Card Model II automatic typewriter.This recorder unit senses the word processing image indicating signals and transfers them under program control to memory 64 whereat SMP 62 performs word processing functions or text processing functions on the received image indicating signals. Such text processing functions are necessary to convert the word processing input into a textual format suitable for use by LI 12B. The details of such text processing become immensely complicated and are dispensed with for purposes of brevity, it being understood that known text processing techniques may be used for converting the received word processing image indicating signals to a format including control signals for use by the copy production machine 10. This mode continues until the hopper 137 of the local terminal 16 is empty. A switch (not shown) in hopper 137 signals to CMP 62 via DI bus that hopper 137 is empty.

This signal signifies that all image indicating signals from word processing input LT 16 have been transferred into copy production machine 10. The hopper empty signal is transferred to SMP 62 for use as will become readily apparent.

The programming of SMP 62 in connection with the initiation of a print mode as requested by LT 16 receiving magnetic record cards (not shown) and actuation of "read" button 155 is shown in Figure 9 and further explained with respect to the code listings included in the specification. It is to be understood that the supplied code listings are those necessary to provide the functions set forth in the claims and do not show all of the functions performed by SMP 62 in supervising the operating copy production machine 10. For example, text processing has been dispensed with as well as diagnostic and other supervisory functions usually performed by programmable computers in connection with controlling machines.Further, source code not necessary to an understanding of the claimed subject matter and which is interleaved with the listed codes has been omitted for purposes of more clearly describing the claimed invention.

Upon receipt of a print job initiating OCL, SMP 62 enters a start print job subroutine via a program path termed "set next job" which corresponds to memory address E874 in Table I below. The start print job at 120 is termed "ACTBACK" which is a shorthand name for activate background print mode. The details of ACTBACK 120 are shown in the Table I below in source code language operable on the above described pipeline processor. In Table I and all other source code tables in this specification the left hand column entitled "LOC" indicates the actual memory location of the instruction word; "OBJ" is the object code itself; the terms "OP1" and "OP2" refer to operands 1 and 2, respectively, and the source statement is the wide right hand column which defines the function being performed by the object code using operands 1 and 2.

MICROCODE TABLE I - ACTIVATE PRINT MODE LOC OBJ OP1 OP2 SOURCE STATEMENT E874 EF 000F ACTBACK LR STATER EXP2 E875 AB88 0088 NI,P(BDDSTF,DDSTF) TEST 2 BITS-ZERO ALL OTHERS E877 46 E886 JE NOTDRK BOTH BITS = 0 EXP2 E878 AD88 0088 XI,P(BDDSTF,DDSTF) E87A 3D91 E891 BE DUPALT BOTH BITS = 1 E87C EF 000F LR STATER STATE = 0/1 | 1/0 E87D 97 0007 TP BDDSTF E87E 61 E811 JNE CDRK E87F 96 0006 TP BLDSTF E880 6D E88D JNE CLT CDRK TSMR FLCNTLR,P(CHNGDRKF) FRGND LT, BCKGND DRK-SO CHANGE E881 E8 0008 E882 AF08 0008 E884 88 0008 *** HARDWARE WILL TURN OFF LT DOC E885 01 E891 J DUPALT E886 EF 000F NOTDRK LR STATER EXP2 NI,P(BLDSTF,LDSTF) MICROCODE TABLE I - ACTIVATE PRINT MODE E887 AB44 0044 E889 41 E891 JE DUPALT BOTH = 0, NO CHANGE REQUIRED EXP2 XI,P(BLDSTF,LDSTF) E88A AD44 0044 E88C 41 E891 JE DUPALT BOTH = 1 SO NO CHANGE REQUIRED CLT TSMR FLCNTLR,P(CHNGLTF) FRGND DRK, BCKGND LT-SO CHANGE E88D E8 0008 E88E AF04 0004 E890 88 0008 *** HARDWARE WILL TURN DARK DOC E891 DUPALT DC * * 1. SET UP DUPLEX FOR PRINT E891 EF 000F LR STATER EXP2 NI,P(BDSTF,DSTF) E892 AB11 0011 E894 4C E89C JE GOOD1 BOTH OFF SO NO CHANGE EXP2 XI,P(BDSTF,DSTF) E895 AD11 0011 E897 4C E89C JE GOOD1 BOTH ARE ON NO CHANGE TSMR FLCNTLR,P(CHNGDUPE) ONE OR THE OTHER IS ON MICROCODE TABLE I - ACTIVATE PRINT MODE E898 E8 0008 E899 AF01 0001 E89B 88 0008 SO TOGGLE STATE OF DUPLEX ** 1.SET UP SUPPLY BIN FOR PRINT * STATER E89C EF 000F GOOD1 LR NI,P(BSSSTF,SSSTF) EXP2 E89D AB22 0022 E89F 47 E8A7 JE GOOD2 BOTH ARE OFF-SO NO CHANGE EXP2 XI,P(BSSSTF,SSSTF) E8A0 AD22 0022 E8A2 47 E8A7 JE GOOD2 BOTH ARE ON-SO NO CHANGE TSMR FLCNTLR,P(CHNGALTF) ONLY ONE WAS ON-SO TOGGLE E8A3 E8 0008 E8A4 AF02 0002 MICROCODE TABLE I - ACTIVATE PRINT MODE E8A6 88 0008 * 1. RESET LIGHTS FOR NUM: PAGES & ADJUST GOOD2 TRMR LIGHTSR,P(ADJUSLTF,NUMPGLTF) E8A7 E9 0009 E8A8 AB9F 009F E8AA 89 0009 * 1. SETUP ADJUST * NUMBER PAGES STATES (NUMPGF ADJUSTF) *C E8AB A63F 023F LBL STATE1B EXP2 NI,P(NUMPGF,ADJUSTF) E8AD AB60 0060 E8AF A729 0229 OBL $LITES2B E8B1 A129 0229 STBL $LITES2B * 1.RESTORE OLD STATES-THIS CLEARS THE BACKGROUND STATES *C E8B3 25 CLA *** E8B4 A62F 022F LBL STATE2B SHRM 4 MICROCODE TABLE I - ACTIVATE PRINT MODE E8B6 2F E8B7 2F E8B8 2F E8B9 2F E8BA A12F 022F STBL STATE2B * 1. RESET READ AND RECEIVE FLASH (READFLF RECVFLF) *C TRMBL $LITESFB,P(READFLF,RECVFLF) E8BC A638 0038 LB $REK874 NI X'FF'-($CA1875+$CA2875+$CA3875+$CA4875+$CA5875+$CA6875+$X CA7875+$CA8875) E8BE AB6F 006F E8CO A138 0038 STB $REK874 * 1. RESET COPY LIGHT (COPYLTF) TRMBL $LITES1B,P(COPYLTF) E8C2 A639 0039 LB $REK878 E8C4 B6 0006 TR COPYLTF E8C5 A139 0038 STB $REK878 MICROCODE TABLE I - ACTIVATE PRINT MODE * 1. SET COPIES REQUESTED=SETS REQUESTED CPYREQR=PRNTREQR) *C E8C7 E5 0005 LR PRNTREQR E8C8 84 0004 STR CPYREQR 1. IF RECORD LIGHT IS ON SOLID (RECRDLTF=1) * 1. THEN *C * E8C9 97 0007 TP RECRDLTF E8CA 40 E8DO JE XMIT * 2. .RESET RECORD FLASH (RECRDFLF) TRMBL $LITESFB,P(RECRDFLF) E8CB A638 0038 LB $REK880 E8CD B1 0001 TR RECRDFLF E8CE A138 0038 STB $REK880 * 1. ENDIF * 1. IF TRANSMIT IS ON SOLID (XMITLTF=1) * 1. THEN E8DO A639 0239 XMIT LBL $LITES1B E8D2 92 0002 TP XMITFLF E8D3 49 E8D9 JE LGHTSGD MICROCODE TABLE I - ACTIVATE PRINT MODE * 2. . RESET TRANSMIT FLASH (XMITFLF) TRMBL $LITESFB,P(XMITFLF) E8D4 A638 0038 LB $REK882 E8D6 B5 0005 TR XMITFLF E8D7 A138 0038 STB $REK882 * 1. ENDIF * 1. TURN DOCUMENT LAMP OFF (DOCLMPF=1) * 1. SELECT PRINT EXIT POCKET (SELPRNTF=1) LGHTSGD TSMR FLCNTLR,P(SELPRNTF,DOCLMPF) E8D9 E8 0008 E8DA AF90 0090 E8DC 88 0009 * 1. SET CHANGES ACTIVE FLAG (CHNGACTF) TSMBL STATE1B,P(CHNGACTF) E8DD A63F 003F LB $RE887 OI $CA1888+$CA2888+$CA3888+$CA4888+$CA5888+$CA6888+$CA7888+X E8E1 A13F 003F STB $REK887 * 1. RESET INHIBIT PRINTING FLAG (PRNTINHF) E8E3 EC 000C LR SOFTJOBR E8E4 B3 0003 TR PRNTINHF E8E5 A12C 022C STBL JOBFLGB * 1. SUBROUTINE EXIT E8E7 21 001 ACTEND RTN BAL1 * ENDBEGIN ACTBACK In the above Table I the first part of the table shows SMP 62 readjusting the copy production machine 10 to accommodate the print mode. For example, the change from light or dark background copier settings to a normal setting. Also the duplex mode is selected if requested by OCL, such as at E89 1 memory address. The copy mode light is extinguished by an instruction at E8C2. The number of copies per set and the number of sets requested are set at by an instruction at E8C7 and other controls incidental to effecting a print job are initialized in ACTBACK 120.

Next, copy production machine 10 receives an image to be printed as at 121.

This image can be supplied through LT 16 or through RTC 17. In either event, the first image to be printed has to be received and placed in page memory 64 after suitable text processing (not described) effected via SMP 62. Once an image is in place in page memory 64 copy production machine proceeds to print an image at 122. Since steps 121 and 122 are a part of the print job and are not a part of the controls for switching between print jobs and copy jobs the actual processing at the instruction level is dispensed with for purposes of brevity, it being understood that any suitable known text processing and image processing type of control may be used.

Upon printing an image as by imposing an image on photoconductor drum 22, and even before the imaged copy sheet has left fuser 31, SMP 62 checks to ensure that the print job is not over and determines the state thereof for determining the next action. Figure 9 shows the overall view of how this is achieved while the details of it will be explained later with respect to Figure 10. First, SMP 62 at 123 checks to see whether or not all images had been received. If not, SMP 62 actuates copy production machine 10 to receive another image to be printed. In this regard it should be noted that the images in page memory 64 may be transferred to nonvolatile store 19 in accordance with precollation techniques as will be later discussed. If all the images are in, i.e.LT 16 has completed its job or RTC 17 has completed its job, then SMP 16 determines whether or not all of the images are set as at 124. What this means is that all of the text processing has been performed by SMP 62 and that most of the image indicating signals had been stored in NVS 19. It should be understood that the image indicating signals per image are shuttled between page memory 64 and NVS 19 for printing successive precollated copies. If all of the images are not set, then SMP 16 returns to the first part of the program to process by text processing another image as at 125. It should be noted herein that before any image is printed text processing functions are performed on it, no limitation thereto intended.If on the other hand, all images had been text processed (set) SMP 62 then proceeds to check whether or not all of the images have been image on photoconductor drum 20, as at 126. If not, another image is printed. If all of the images had been impressed upon photoconductor drum 20, i.e., all copies have been started and all that remains is for copy production machine 10 to transport the imaged copy sheets to output portion 14.

Then, no more imaging is performed and SMP 62 proceeds for terminating the print job.

In terminating a print job, first SMP 62 determines at 127 whether or not there were any error conditions occurring during the print job. If yes, error conditions will be printed on a so-called summary sheet which is another imaged copy sheet supplied with the imaged print copies for use by the machine operator. Typically a printed summary sheet would be text from NVS 19 and memory 64 containing error data and operational problems and be printed as a regular print copy in a predetermined format. Such summary sheets assist the operator in successfully operating copy production machine 10 particularly when certain errors have occurred. A collection of such summary sheets are an efficient diagnostic aid to maintenance personnel for maintaining successful operation of copy production machine 10.

If there are no errors detected at 127 SMP 62 then proceeds to branch instruction at 128 to determine whether or not OCL initiating the print job had requested a job report in the form of a summary sheet. If yes, copy production machine 10 prints the summary sheet indicating no errors and indicating parameters of the print job. (Margins, etc.) SMP 62 after having determined the last printed copy sheet has successfully been transported to output portion 14B sets the copy mode at 130. It should be noted herein that the summary sheet being printed at 129 does not start until SMP 62 has determined successful completion of the print job which includes depositing the last copy sheet successfully in output portion 14B. For purposes of simplicity the wait loop necessary for SMP 62 to hold the print job summary sheet initiation is dispensed with because wait loops are so well known.

Before the "set next job" can be performed as at 120 by SMP 62 it must verify that the copy mode switch 135 (Figure IB) has not been actuated. If actuated, a copy mode job will be performed. This determination is achieved in a three instruction subroutine shown below in Microcode Table II Sense Copy Mode Switch. This routine merely consists of an input instruction which receives the switch 135 setting via input registers 173 (Figure 2) and then branches upon the input instruction to either set next job at 120 or perform copy mode operations (not herein described).

Further, the set copy mode 130 is shown in Microcode Table III Begin Print Job End. If this microcode routine senses if the drive motor of the copy production machine which rotates photoconductor 20 is not being energized (drive low), this state indicates an end of print job end has occurred, then SMP 62 executes branch instruction 128 to print summary sheet 129. After the summary sheet is printed, the copy mode will be reinstalled as an inactive foreground state. These actions are shown in Microcode Table III below.

MICROCODE TABLE II- SENSE COPY MODE SWITCH LOC OBJ OP1 OP2 SOURCE STATEMENT 263 A637 0237 NTCK LBL SWST3B E26 92 0002 TP COPYSWF E266 356E E36E BE CHKINV MICROCODE TABLE III - BEGIN PRINT JOB END (PROJBEND) LOC OBJ OP1 OP2 SOURCE STATEMENT ** * BEGIN PRJOBEND * 1. IF DRIVE IS LOW & JOB END HAS OCCURRED *C (DRIVESTF = 0 & JOBENDF = 1) DDEF E7 0007 CHKPRJEN LR SWST2R DDF0 97 0007 TP DRIVESTF DDF1 346A DE6A BNF ENDPJEND DDF3 EC 000C LR SOFTJOBR DDF4 B5 0005 TR JOBENDF DDF5 356A DE6A BE ENDPJEND Returning now to SMP 62 terminating a print job, more detailed description of such termination is shown in Figure 10. The print job control steps include items 120 thru 126 of Figure 9.When all the images are completed the subroutine shown in Figure 10 is entered at branch instruction 136; i.e., the Figure 10 subroutine is interposed between branches 126 and 127 of Figure 9. With different machine configurations it is to be understood that the Figure 10 subroutine would be changed accordingly.

SMP 62 having determined that all images are finished as at 126, it then determines the type of image input at 136. If it is a word processing WP input from LT 16 then the LT 16 hopper 137 is checked to determine whether or not it is empty, as at 138. If hopper 137 is not empty, the print job mode is left active. That is, in copy production machine 10, hopper 137 may receive a plurality of jobs to be automatically and successively printed. Each job would be started by a so-called OCL card which would denominante the parameters of the print job to copy production machine 10. When a given print job from LT 16 is being completed it is necessary for the copy production machine 10 via SMP 62 to sense whether or not there are more jobs in hopper 137.If hopper 137 is empty, then the end print job routine of Figure 9 including items 127-130 is entered including setting copy mode at 130.

On the other hand, if the images being printed are received via RTC 17 in the communications mode (COMMO) then the character of the job assignment must be examined by SMP 62. To this end it first determines whether or not copy production machine has been placed in a dedicated receive mode, such as by the image sending remote station 18 via the OCL transmitted just prior to, during, or after the print job. On dedicated receive mode copy production machine 10 automatically sets up the next communication job at 141 and then automatically performs the printing in accordance with the received image indicating signals.

Accordingly, if copy production machine is in the dedicated receive mode then it must always set up a print job in the communication mode at 141. Code listings for the routine of 141 are omitted for brevity in that programmed reception of image indicating signals are well known. Upon executing routine 141 SMP 62 then sets the next job via memory address ES74 and starts printing again as soon as image indicating signals are received, if any. In the dedicated receive mode, copy production machine 10 always has the print mode as the normal active foreground operational state. In the dedicated receive mode, source 18 may typically be a data processing system 18A, 18B. In this instance copy production machine 10 is a computer output peripheral interruptible to perform a manually actuated function in the computer peripheral.

If, on the other hand, copy reproduction machine 10 is not in the dedicated receive mode (not on communication all of the time) it proceeds to determine what the image signal sending source 18 has indicated as a job termination. In accordance with known communication protocol, sessions, i.e., transmission periods, of sending image indicated signals to copy production machine 10 dictate that jobs can be ended by indicating end of text, ETX, or at end of transmission, EOT. Therefore, a branch at 140 determines the type of termination required by the sending source 18. If EOT, SMP 62 detects whether or not an EOT character has been received at 142. If not, the print job is then resumed; if yes, the print job is ended. Similarly, ETX branch 143 looks for the character ETX and performs the same functions as described for EOT.

The above portions of the print job are for uninterrupted print jobs; i.e., where a print job has been requested and the print mode has been changed from a background mode to a foreground operating state. The copy mode, which is a foreground operating mode, is relegated to the background operational state while the print mode is active. However, upon a request that a copy mode be instituted in copy production machine 10 the print mode is automatically relegated to a background operational state while the copy mode is activated into the foreground operational state until all copies have been made. At that point the print mode is automatically reinstituted as the active foreground state as will become apparent from the immediately following description.

Copy Selection Interruption of Active Print Mode The sequence of operations of copy production machine 10 in responding to a copy request during a print job or dedicated receive mode for interrupting the print job is shown in Figure 11. SMP 62 periodically scans copy select switch 135 as set forth in Table II, supra. In Figure 11 the sensing of copy mode switch 135 at 150 may result in a branch operation indicating that the copy mode was not selected. In such a situation the Figure 11 illustrated program is exited. On the other hand, if the copy mode switch 135 is set, then SMP 62 executes the program set forth in Table IV which implements the three functions identified in flow chart blocks 151, 152, 153 which respectively sense print mode conditions for cycling out the print job and activating the copy mode. All of these functions are set forth in Table IV immediately below.

MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE LOC OBJ OP1 OP2 SOURCE STATEMENT E2D9 31E8E9 0001 E9E8 BAL BAL1,BAL41 E2DC 246D E36D B COPYEX * 2 . . ELSE PRINT SYSTEM NOT IDLE * 3 . . IF PRINT SYSTEM IS HALTED (SULPHALTF = 1) *C PRNTBCK SRG GROUPSU E2DE A9C7 00C7 SUPERB E2E0 A6E4 00E4 LBL SUPHALTF E2E2 B2 0002 TR SUPERB E2E3 A1E4 00E4 STBL GROUPCD SRG CCIP E2E5 A9D1 00D1 E2E7 4C E2EC JE * 3 . . THEN * 4 . . RESET PRINT SYSTEM HALT FLAG-CODED ABOVE (SUPHALTF) *C 4 . . RESET PG PROC. COPYMODE (PRNTINHF) * E2E8 EC 000C LR SOFTJOBR E2E9 B3 0003 TR PRNTINHF E2EA A12C 022C STBL JOBFLGB MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE * 3 ... ENDIF * 3 . . NOTE JAMS HAVE ALREADY BEEN LOOKED FORE *C 3 . . IF DRIVE HIGH (DRIVESTF = 1) * E2EC E7 0007 CCIP LR SWST2R E2ED 97 0007 TP DRIVESTF E2EE 3509 E309 BE STDUPLX * 3 . . THEN * 4 . .STILL ACTIVELY PRINTING SO SET NOT READY LIGHT AND COPY SWITCH FLAG (NTRDYLTF; *C COPYSWF) AND WAIT FOR PRINT TO FIND CONVENIENT STOPPING POINT *C *C *C TSMR LIGHTSR,P(NTRDYLTF) E2F0 E9 0009 E2F1 AF10 0010 E2F3 89 0009 TSMBL SWST3B,P(COPYSWF) E2F4 A637 0037 LB $REK494 OI $CA1495+$CA2495+$CA3495+$CA4495+$CA5495+$CA6495+$CA7495+X E2F6 AF04 0004 $CA8495 E2F8 A137 0037 STB $REK494 MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE * 4 . . IF NOT IN DUPLEX STATE OR NO COPIES IN DUPLEX TRAY (DSTF = 0 | CIDTF = 0) *C *C E2FA EF 000F LR STATER E2FB 90 0000 TP DSTF E2FC 3502 E302 BE PRNTSTOP E2FE E6 0006 LR SWST1R E2EF 96 0006 TP CIDTF E300 3C6D E36D BNE COPYEX * 4 . . THEN * 5 . . SET INHIBIT PRINTING FLAG (PRNTINHF) *C E302 EC 000C PRNTSTOP LR SOFTJOBR E303 AF08 0003 TS PRNTINHF E305 A12C 022C STBL JOBFLGB E307 2C6D E36D B COPYEX * 4 . . ENDIF * 3 . . ELSE * 4 . . IF IN DUPLUX MODE (DSTF = 1) E309 EF 000F STDUPLX LR STATER E30A 90 0000 TP DSTF E30B 3D1D E31D BE PRNTCOPY MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE * 4. .THEN * 5. .IF COPIES IN DUPLEX TRAY (CITDF = 1) *C SWSTIR E30D E6 006 LR CITDF E30E 96 006 TP PRNTCOPY E30F 3D1D E31D BE * 5. .THEN * 6. .REMEMBER THAT PRESENTLY NO ERROR *C RECOVERY FOR PRINT DUPLEX *C * 6. .SET FLAG TO WAIT FOR PRINT DUPLEX JOB TO FINISH (NTRDYLTF COPYSWF) *C *C TSMR LIGHTSR,P(NTRDYLTF) E311 E9 009 E312 AF10 0010 E314 89 0009 TSMBL SWST3B,P(COPYSWF) E315 A637 0037 LB $REK499 OI $CA1500+$CA2500+$CA3500+$CA4500+$CA5500+$CA6500+$CA7500+X MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE E317 AF04 0004 $CA8500 E319 A137 0037 STB $REK499 E31B 2C6D E36D B COPYEX * 5. .ELSE * 6..CHECK PGERRCOV SUBROUTINE & SET *C CONDITIONS TO GO TO COPYMODE DONE BELOW TO SAVE CODE *C *C * 5. . .ENDIF * 4. .ELSE SET UP CONDITIONS TO GO FROM PRINT TO COPY MODE *C * 5. .CALL PGERRCOV PAGE ERROR RECOVERY SUBROUTINE *C E31D 31E8E8 0001 E8E8 PRNTCOPY BAL BAL1,PGERRCOV * 5. .SET COPY REQUEST REGISTER = 1 (CPYREQR) *C E320 25 CLA *** E321 2E A1 *** E322 84 0004 STR CPYREQR MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE * 5. . .RESET LIGHTLIGHT,DARK, ALTERNATE, & BR< DUPLEX IF ON (CHNGLTF, CHNGDRKF, *C CHNGALTF, CHNGDUPF) *C *C E323 EF 000F LR STATER E324 A728 0228 OBL CPYCNTLB E326 A128 0288 STBL CPYCNTLB * 5. .SAVE PRINT STATES TO BACKGRND (HIGH NIBBLE-STATE2B) *C * 5. .RESET FOREGROUND STATES (DDSTF,,LDSTF, *C SSSTF,DSTF) E328 EF 000F LR STATER SHLM 4 E329 2B E32A 2B E32B 2B E32C 2B E32D A12F 022F STBL STATE2B * 5..TURN ON DOCUMENT LAMP (DOCLMPF) * 5. .SELECT COPY EXIT POCKET (SELPRNTF = 0) *C TRMR FLCNTLR,P(DOCLMPF,SELPRNTF) MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE E32F E8 0008 E330 AB6F 006F E332 88 0008 * 5. .MOVE PRINT ACTIVE LIGHTS TO FLASHING & SET COPY LIGHT *C E333 E9 0009 LR LIGHTSR E334 A638 0238 LBL $LITESFB E336 29 TRA *** E337 AF40 0006 TS COPYLTF E339 95 0005 TP READLTF E33A A4 E33F JE CHKXMITL E33B 29 TRA *** E33C AF80 0007 TS READFLF E33E 29 TRA *** E33F 92 0002 CHKXMITL TP XMITLTF E340 45 E3455 JE CHKRCVL E341 29 TRA *** E342 AF20 0005 TS XMITFLF E344 29 TRA *** E345 91 0001 CHKRCVL TP RECVLTF MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE E346 4B E34B JE CHKRCDRL E347 29 TRA *** E348 AF10 0004 TS RECVFLF E34A 29 TRA *** E34B 97 0007 CHKRCRDL TO RECRDLTF E34C 29 TRA *** E34D 40 E350 JE SUBEX E34E AF02 0001 TS RECRDFLF E350 A138 0238 SUBEX STBL $LITESFB E352 29 TRA *** E353 A139 0239 STBL $LITES1B * 5. .RESET NUMBER PAGES & ADJUST LIGHTS (NUMPGLTF ADJUSLTF) *C TRMR LIGHTSR,P(NUMPGLTF,ADJUSLTF) E355 E9 0009 E356 AB9F 009F E358 89 0009 * 5. . .SET COPY FIRST ENTRY TSMBL CONFLG2B,P(CPYFRSTF) E359 A63D 003D LB $REK508 OI $CA1509+$CA2509+$CA3509+$CA4509+$CA5509+$CA6509+$CA7509+X MICROCODE TABLE IV - COPY MODE INTERRUPTS PRINT MODE E35B AF04 0004 $CA8509 E35D A13D 003D STB $REK508 * 5. . .SET CHANGES ACTIVE FLAG (CHNGACTF) *C STATE1B,p(CHNGACTF) TSMBL E35F A63F 003F LB $REK511 OI $CA1512+$CA2512+$CA3512+$CA4512+$CA5512+$CA6512+$CA7512+X E361 AF02 0002 $CA8512 E363 A13F 003F STB $REK511 * 5. . .RESET NOT READY LIGHT (NTRDYLTF) TRMR LIGHTSR,P(NTRDYLTF) E365 E9 0009 E366 B4 0004 E367 89 0009 * 5..SET INHIBIT PRINTING FLAG (PRNTINHF) *C E368 EC 000C LR SOFTJOBR E369 AF08 0003 TS PRNTINHF E36B A12C 022C STBL JOBFLGB At flow chart block 151, SMP 62 checks for print jams (misfeeds) and maintains the status of the copies requested, copies made, number of originals to be printed and so forth. SMP 62 takes this print mode data and stores it in memory 64.

In the alternative SMP 62 can be programmed to store the print mode recovery information in NVS 19. In cycling out the print mode in flow chart step 152, which includes instructions stored at address E332, the print active lights are flashing indicating the print job has been interrupted. The cycling out of print mode also is synchronous to an image cycle. That is, a complete print copy has been made by CPP 13 before the copy mode is installed at step 153. When operating in the duplex print mode, because of the precollation of images by precollating image indicating signals, during production of the first set the interim storage unit 40 will never have more than one sheet of paper at a time. In such a situation the copy production machine 10 completes printing the second side of any sheet in interim storage unit 40.Therefore, the copy mode must wait until after a copy sheet has been completely imaged during the print mode. For subsequent sets in the duplex print mode, copy mode interruption occurs at the end of each set, as later explained. Of course in simplex printing, i.e., images on only one side of the copy sheet, interim storage unit 40 is not used.

Included in setting up the copy mode in step 153 is resetting the number of sheets to be printed by CPP 13 and adjusting the lights of the operator's control panel 52 as achieved by the instructions stored beginning at E353.

From flow chart step 153 SMP 62 actuates CMC 16 to execute the copy mode.

Since the operation of copy machines in copy modes are well known, that program is not further described for purposes of brevity, it being understood that any form of copy control may be used in connection therewith.

The next major step performed by SMP 62 is at flow chart step 154 which detects the end of the copy mode being active and reestablishes the print mode as the foreground operating state of copy production machine 10. The microcode listings for achieving flow chart step 154 are shown in Microcode Table V immediately below.

MICROCODE TABLE V - DEACTIVE COPY MODE LOC OBJ OP1 OP2 SOURCE STATEMENT E227 E8 0008 LR FLCNTLR E278 94 0004 TP DOCLMPF E297 3CA1 E2A1 BNE COPYPM * 1.THEN * 2..IF COPIER IS NOT BUSY (CPYBSYF = 0) E27B E6 0006 LR SWST1R E27C 96 0006 TP CPYBSYF E27D 3C9F E29F BNE LCOPYEX * 2..THEN * 3. .IF PRINT SYSTEM IS NOT IDLE (PRNTIDLE = 0) *C E27F EC 000C LR SOFTJOBR E280 97 0007 TP PRNTIDLF E281 246D E36D BNE COPYEX * 3. .THEN * 4. .IF DRIVE IS UP (DRIVESTF = 1) E283 E7 0007 CIF LR SWST2R E284 97 0007 TP DRIVESTF E285 4E E28E JE CIFX MICROCODE TABLE V - DEACTIVE COPY MODE * 4. .THEN * 5. .NOTE SAVE FACT COPY SWITCH PUSHED *C * 5. .SET COPY SWITCH (COPYSWF) TSMBL SWST3,P(COPYSWF) E286 A637 0037 LB $REK465 OI $CA1466+$CA2466+$CA3466+$CA4466+$CA5466+$CA6466+$CA7466+X E288 AF04 0004 $CA8466 E28A A137 0037 STB $REK465 * BEGIN TIMEOUT COPIER TIME OUT SEGMENT DE7E E8 0008 TO LR FLCNTLR DE7E 94 0004 TP DOCLMPF DE80 3406 DF06 BNE TOPM * 1.THEN * 2..PROCESS CKIDLPRT INCLUDE CKIDLPRT * BEGIN CKIDLPRT (SPLIT FROM TIMEOUT) * 1.IF PRINT SYSTEM IS IDLE (PRNTIDLF = 1) DE82 EC 000C CMNJE LR SOFTJOBR DE83 97 0007 TP PRNTIDLE DE84 3DF0 DEF0 BE CMNI MICROCODE TABLE V - DEACTIVE COPY MODE * 2..ENDIF * 2..IF DRIVE IS LOW & COPIER TIMEOUT HAS * OCCURRED (DRIVESTF = 0 & TIMEOUTF = 1) *C DE73 E7 0007 CHKCPYTO LR SWST2R DE74 97 0007 TP DRIVESTF DE75 3413 DF13 BNE CHKADINT DE77 A636 0236 LBL SWST1B DE79 B6 0006 TR TIMOUTF DE7A 3513 DF13 BE CHKADINT * 2..THEN * 3..REST COPIER TIMEOUT FLAG (TIMOUTF) DE7c A136 0236 TOX STBL SWST1B * 3. .PROCESS TIMEOUT COPIER TIMEOUT SEGMENT *C * 2..ENDIF * 1.ELSE PRINT SYSTEM NOT IDLE * 2..IF DUPLEX TRAY IS EMPTY (CIDTF = 0) * 2..THEN FLCNTLR DEFO E8 0008 CMNI LR CIDTF DEF1 96 TP DEF2 3413 DF13 BNE CHKADINT MICROCODE TABLE V - DEACTIVE COPY MODE * 3. .CALL ACTBACK ACTIVATE BACKGROUND SUBROUTINE *C DEF4 3174E8 0001 E874 TIMBACK BAL BAL1,ACTBACK E372 344A E44A BNE READEXIT ACTUALLY A BRANCH TO CKQUN * 5. .THEN * 6..IF READ SWITCH WAS SELECTED & NOT DUMP OF DUPLEX *C (READSWF = 1 & DODIPF = 0) *C E374 A637 0237 LBL SWST3B E376 95 0005 TP READSWF E377 354D 344D BE CHKRCD E379 A63F 023F LBL STATE1B E37B 93 0003 TP DODIPF E37C 344D E44D BNE CHKRCD * 1.IF SYSTEM IS IN COPY MODE (DOCLMPF = 0) E391 E8 0008 LR FLCNTLR E392 94 0004 TP DOCLMPE E393 3CF5 E35F BNE READPM GO CHECK PRINT MODE * 1.THEN * 2..IF COPIER IS NOT BUSY (CPYBSYF = 0) MICROCODE TABLE V - DEACTIVE COPY MODE E395 E7 0007 LR SWST2R E396 96 0006 TP CPYBSYF E397 344A E44A BNE READEXIT GO EXIT READ SWITCH SEG * 2 .. THEN * 3 . .IF DRIVE = & (COPIES IN DUPLEX TRAY OR PRINT NOT IDLE) SHOULD THIS BE FOR *C DRIVE = 1 ONLY ?????????? (DRIVESTF = 1 & BR< CITDF = 1) | (DRIVSTF = 1 & (IDTF = 0 & BR< *C PRNTIDLF = 0) *C *C *C E399 97 0007 TP DRIVESTF E39A 3DAA E3AA BE DRIVEDC * 4..IF COPIES ARE IN DUPLEX TRAY (CITDF = 1) *C E3AA E6 0006 DRIVEDC LR SWST1R E3AB 96 0006 TP CITDF E3AC 3D89 E3B9 BE CHKIPI * 4. .ELSE DUPLEX TRAY EMPTY * 5. .IF PRINT SYSTEM IS IDLE (PRNTIDLF = 1) *C MICROCODE TABLE V - DEACTIVE COPY MODE E389 EC 000C CHKIPI LR SOFTJOBR E3BA 97 0007 TP PRNTIDLF * 6......CALL ACTBACK ACTIVATE BACKGROUND SUBROUTINE *C E3F0 3174E8 E874 BCKGRND2 BAL BAL1,ACTBACK Termination of the active copy mode can be achieved in several ways. The operator may repress the copy select switch 135 deactivates the copy mode.

At such time the print mode is eligible to be elevated to the foreground operational state of copy production machine 10. The first portion of the microcode program in Table V is for sensing the copy mode switch 135 for reestablishing the activity of the print mode.

A second way of terminating the copy mode activity is a timeout (not shown) in the copier control CMC 61 which supplies a pulse indicating that a predetermined time has elapsed since the last copy was made. At this time the copy production machine 10 MPMC 15 automatically deactivates the copy mode and reactivates the print mode. This is achieved via the sequence of instructions beginning at memory adress E372.

Another way of terminating the activity of the copy mode is the selection by an operator of using local terminal 16 as an input to the copy production machine 10.

This action is achieved by activating read switch 155 on control panel 52.

Activation of read switch 155 signifies an operator desire to go from a copy mode to a word processing input mode for printing copies. Accordingly, copy production machine 10 responds to such an indicated desire on the part of the operator to deactivate the copy mode and reinstitute the activity of the print mode. At this time it should be noted that the print job currently interrupted will be completed before the word processing job requested by the operator will be started.

Upon detecting any of the three above described conditions, SMP 62 actuates the ACTBACK subroutine at memory routine E874 as set forth above in Table I.

ACTBACK program is executed by SMP 62 in such a manner as to recover the information stored in flow chart step 151 such that the print job is reinstituted at the appropiate place and that no print copies are missed and that no excessive print copies are made.

Copy Selection Interruption Point Control In Duplex and Simplex Printing In either the simplex (single-sided printing) or the duplex (two-sided printing) copy production machine 10 can receive images via either local terminal 16 or remote terminal connector 17. In either instance it is desired for throughput considerations to overlap the reception of image indicating signals, text processing of those received image indicating signals, with the production of a first set of print copies to be made in accordance with received OCL instructions. Such overlapping and setting up is achieved as shown in steps 160 thru 167 of Figure 12. In the production of subsequent print sets, all of the image signals have been processed and stored in NVS 19, hence the procedure for printing subsequent print sets varies from that for printing the first print set as will become apparent.

In step 160, MPMC 15 interprets the OCL for setting up a print mode, as shown for a duplex print mode. Step 160, in the event of receiving image indicating signals from LT 16, is initiated when the read button switch 155 selects LT 16 as an input followed by closure of start button 180. Then MPMC 15 actuates LT 16 to read the word processing first card (not shown), previously inserted into inlet slot 137. The first card (not shown) contains OCL indicating signals which include the selection of the duplex mode (duplex mode may be selected via panel 52, as well) as well as other parameters such as margins, line spacing, font style, and the like, beyond the scope of the present description. In step 160 MPMC 15 decodes the received OCL signals and sends out instruction signals to the various portions of copy production machine 10 for implementing the received OCL.Once the OCL signals have been received, decoded, and copy production machine 10 set up for duplex printing operations, the machine is ready to read the second card (not shown) in the stack of cards (not shown) within slot 137. Reading a card (not shown) is performed at step 161 as receiving one imge; i.e., one word processing card may correspond to one page of print, for example. Two such pages are on one copy sheet. Signals from the reader/recorder (not shown) of local terminal 16 are directed to page memory 64 under control of DMA 64A. Once the image indicating signals are in page memory 64, the completion of the reading of one track or line of a word processing card (not shown) LT 16 signals SMP 62 to begin text processing.

Once text processing is completed for the first or subsequent odd numbered page it is printed as at 162. Simultaneously therewith, or in sequence depending on how one wants to construct the machine, in the particular instance the printing occurs simultaneously with the reception of the second image signals at 163. For odd page printing in duplex mode D, CPP 13 transfers the print copy to interim storage unit (ISU) 40, whereas in the simplex mode S the print copy goes directly from CPP 13 to output portion 14B. In this regard the interrupt point XS (interrupt during simplex mode) 164 indicates the print production interruption point enabling interruption of the simplex print mode by copy mode selection.

As soon as the steps 162, 163 are completed, the second or subsequent evennumbered image received at 163 having been text processed can be printed as an even numbered page in step 165. In both simplex and duplex print modes, the print copy goes to output portion 14B. This action represents completion of the printing of one or more sheets of copy paper. At this point in time the sheet of paper in the duplex mode sent to ISU 40 has been retrieved and processed through CPP 13 to output portion 14B. Accordingly, CPP 13 has no interim stored partially completed print copies. CPP 13 is available for interruption in the duplex mode as indicated by the symbol XD 166. Accordingly, during the print copy production of any first print set, copy selection interruption may occur at the completion of the printing of any sheet of paper.

In branch step 167 MPMC whether or not the last page of the print set has been received. For example, the OCL decoded in step 160 may contain information indicating that 92 pages are to be printed on 46 sheets of copy paper. In executing the OCL instruction, the number of pages are merely counted through the end of the print job. Steps 161 thru 165 are repeated until the last page has been received from LT 16 or RTC 17 and printed as the first print set, at which time step 168 is entered. This step is a wait step waiting for the first print set to be substantially printed by CPP 13. In this regard, depending upon the error recovery or job recovery techniques employed with copy production machine 10, step 168 may be exited either when the last sheet of paper of the first print set leaves CPP 13, the last sheet has been picked from ISU 40, or the last sheet has been finally deposited in output portion 14B. It is preferred that the MPMC 15 program control exits step 168 to begin the printing of the second and subsequent sets of print copies as soon as the last copy sheet has been deposited in output portion 14B. This selection simplifies automatic job recovery procedures.

It has been stated earlier that the image indicating signals, as text processed by SMP 62, are stored in NVS 19. SMP 62 retrieves those stored image indicating signals in a predetermined order for insuring a proper collated set in output portion 14B. This collation is achieved by printing odd numbered pages first beginning with the highest odd numbered pages and proceeding to the lowest odd number page.

This production sequence of the odd numbered pages places the highest odd numbered page at the bottom of ISU 40 and the lowest odd numbered page as the top sheet in ISU 40. Then MPMC 15 actuates copy production machine to print the even numbered pages beginning with the lowest even numbered page. The first sheet picked from ISU 40 has the lowest odd numbered page. It also receives the lowest even numbered page. CPP 13 then deposits same in the bottom portion of output portion 14B odd numbered page facing down. The second sheet contains the next highest odd numbered page receives the next even numbered page and is deposited on top of the previously printed page in output portion 14B, and so forth.

Accordingly, the collated sets as stacked in output portion 14B have the lowest odd numbered page facing downward at the bottom of each print set and the highest even numbered page facing up on top of each print set. The general equation for this procedure is for even numbered pages, the page being printed at a given instant is 2(N - K), where N is the total number of sheets to be printed, and K is the number of completed printing cycles for even numbered pages; i.e., page number.

In the case of odd numbered pages the page being printed is 2K + 1 until the number of pages equals 2N - I where K is the number of complete print cycles in printing odd numbered pages.

Returning to Figure 12 step 162A executed by SMP 62 actuates copy production machine 10 to print the odd numbered pages and supply same to ISU 40 as above described. Then, at step 165A copy production machine 10 prints the even numbered pages and supplies the printed pages to output portion 14B. Upon completion of step 1 65A all print copies have been removed from CPP 13 and supplied to output portion 14B. At this point CPP 13 is available for copy selection interrupt as indicted by the symbol XD 166A. At all other times during the execution of steps 162A and 165A copies reside in ISU 40. Since a copy selection may employ the duplex mode and since ISU 40 is shared between the copy mode and the print mode, CPP 13 must be clear of copies prior to permitting copy mode interruption.Of course, in a simplex mode any completion of each page allows interruptions, such as at access 164A; i.e., copy mode interruption of the simplex print mode is at the end of each sheet.

Leaving step 165A SMP 62 enters branch step 169. In step 169 SMP 62 determines whether or not the last set has been successfully printed and supplied to output portion 14B. If not, steps 162A, 165A are repeated for printing successive sets. After the last set has been successfully printed the program is exited and the copy mode is again set up as the inactive foreground mode as described above.

Copy Selection Interruption Timing Control Figure 13 illustrates the logic of ascertaining permission to interrupt the print mode. Auxiliary control logic for sequencing CPP 13 is not shown for simplifying the description and for making it more pointed to the task at hand. The foreground mode is indicated by latch 181, the output P indicating print mode, output C indicating copy mode. Latch 181 is set to the C state via OR circuit 182 by the POR signal on line 183 during power on reset, upon completion of a print job by the signal on line 184 (and later explained) or by the output of AO AND input, OR output circuit 185 via line 197 for timing a copy selection interrupt. Latch 181 is set to the P state by AO circuit 186 at the end of a copy interrupt function or when the copy mode is inactive but still in the foreground state and a print request is received over line 187.

Copy interrupt latch 190 memorizes a copy selection interrupt request such that the illustrated circuits can force foreground mode latch 181 to the copy foreground state at the appropriate copy interrupt time. Copy interrupt latch 190 is set to the interrupt active state upon receiving a copy interrupt request signal over line 191. Such an interrupt signal can be generated in diverse ways. A copy interruption cycle is conditioned for activation by actuation of copy mode switch 135 which sets a memory latch (not shown) memorizing a single depression of the switch. Copy production machine 10 then becomes active in the copy mode. Start button 180 then can start actual copy production in the copy mode via OR circuit 194 which sends a copy request signal to CPP 13.Alternately, preentry switch 195 being actuated by an operator inserting a document into SADF 11 actuates copy production in the copy mode. Actuation of CPP 13 in the copy mode is the same as Copier Series III is actuated; that machine is manufactured by International Business Machines Corporation, Armonk, N.Y. The above described control arrangement does not enable the operator to inhibit copy selection interruption of a print mode job. The copy mode is selected and must be deselected by time 208 (later described) or terminated as described elsewhere. To enable operator override of the copy selection interrupt, a second depression of copy mode switch 135 can be made to reset the memory latch (not shown) removing the copy mode request selection.

When the copy mode is selected, an enabling signal travels over line 192 partially enabling AND circuit or interrupt detector 193. AND circuit 193 is also partially enabled by the foreground mode latch 181 being in the P state. Copy interrupt latch 190 does not at that time actually interrupt copy production machine 10 print foreground mode. Actual timed interruption is determined by the logic of operations described below.

The copy selection interrupt can also be made dependent on OR circuit 194 indicating that the operator has readied the copy production machine 10 for copying. That is, the interrupt signal on line 191 would then be supplied by AND circuit 193 only when an output from OR circuit 194 indicates that start button 180 of panel 52 has been activated or the pre-entry switch 195 indicates a document resides in document tray 11 A simultaneously with or after the copy mode switch 135 was activated and copy production machine 10 is in a print foreground mode.

In timing the interruption, AO circuit 185 responds to predetermined conditions to set foreground mode latch 181 to the copy state. The signal on line 191 goes to both the Al and A2 AND circuit input portions of AO 185. The Al input portion in one version interrupts the print mode when duplex has been selected in CPP 13 as indicated by the duplex signal on line 196, and ISU (Interim Storage Unit) 40 has switch 41 supplying signal over line 45 indicating whether or not a copy is in the storage unit. When switch 41 indicates ISU 40 is empty, the empty signal on line 45 completes the enablement of the Al input portion for supplying a latch setting signal over line 197 and through OR circuit 182 setting foreground mode latch to the C state. It is also preferred that all copies made for a print mode job be clear of CPP 13 before copy selection interrupt can occur.Jam circuits 200 supply a "paper patch clear" signal over line 204 to both AO 185 Al and A2 portions for inhibiting the interrupt until the paper path (not shown) of CPP 13 is clear.

Simultaneously with the above described actions, the timed copy selection interrupt signal on line 197 conditions copy path or jam detection circuits 200 for handling the transition between the print mode and the copy mode. Further, the line 197 timed copy selection interruption signal conditions AND circuit 201 tc pass any jam correcting signals from jam circuits 200 received over line 202. Since the present invention is not concerned with job recovery of a paper jam occurring at the transition between the print mode and the copy mode, the operation of AND circuit 201 is not further described. Print counter 203 contains a count indicating the number of sheets of paper picked from blank paper supply 35.If three sheets ol print copies are lost because of a jam, then three is subtracted from the count in counter 203 via AND 201 for ensuring completion of the print job even under error conditions. Operation of counter 203 and the tally of copies produced will be described later.

In setting foreground mode latch 181 to the Ç state, the Al input portion of AO 185 is also controlled by the copy production state in the duplex mode. In this regard the general counter control of copy production machine 10 for producing plural print sets will be described before the control of AO 185 is described. The number of pages to a print set may not be registered within copy production machine 10. Accordingly, during printing the first print set, the pages are counted in print counter 203, then transferred to print select register 205 when EOT or ETX (later described) signals indicate end of a print job set of print signals. AND circuits 209 respond to EOT/ETX in the print mode (latch 181 in P state) to pass the counter 203 signals. Simultaneously, AND circuit 209A passes the EOT/ETX signal via OR circuit 206A as a later described end of set or complete signal on line 207.

On the other hand, OCL could contain signals indicating the number of sheets in a print set. In such an instance, decoded print data is inserted into print select register 205 with a decoded inhibit signal supplied over line 205A to inhibit operation of AND circuits 209 and 209A. That is, OCL signals previously decoded by MPMC 15 may include print data signals stored in print select register 205 which indicates the number of pages to be produced in one print set; for example as stated above, 92 pages were printed in a print set. These 92 pages required 46 sheets; therefore, print select register 205 is set to 92 for counting the pages. Such print data signals could be either from OCL or from the control panel 52.

Compare circuit 206 compares the signal contents of print select register 205 and print counter 203 to determine when one print set has been printed. Compare circuit 206 then emits a complete signal over line 207 to CPP 13, jam circuits 200, timer 208 (used in the copy mode), and to print set counter 210. The complete signal also travels through OR circuit 211 for completing enablement of the Al input portion of AO 185 for setting foreground mode latch 181 to the C state thereby effecting interruption of the print mode when one print set has been completed.

It will be remembered that during the production of the first set the completion of any even numbered image production enables a copy selection interrupt. In this regard, print-set counter 210 supplies its "count equal to one" signal over line 212 through OR circuit 211 to enable the Al input portion of AO 185 during the production of the first print set enabling interruption after production of any even numbered print copies. Additionally, it is desired to have the interruption actually occur in the predetermined portion of a print copy cycle.

This timing is determined by CPP 13 supplying a timing signal over line 213 to both the Al and A2 input portions of AO 185. Such timing signal is emitted at a predetermined synchronous point in CPP 13 cycles of operation determined by the operational characteristics of copy production. Therefore, the signal supplied by AO 185 over line 197 is synchronous to the operation of CPP 13.

The copy selection interruption of a simplex print mode is achieved through the A2 input portion of AO 185. This interruption occurs when the signal from line 207, the timing signal on line 213, the line 191 copy select signal, and a simplex operation mode indicating signal on line 214 supplied by CPP 13 are all simultaneously active.

Termination of the print mode is determined by print set counter 210 reaching equality with the requested number of sets in print set selection register 215 previously set either from panel 52 or by MPMC 15 responding to OCL signals.

When MPMC 15 detects no OCL print set count, register 215 is conditioned to receive panel 52 ten key count input, as well known in the arts. Compare circuit 216 supplies a print mode terminating signal over line 217, thence to line 184 and OR circuit 182 for setting foreground mode latch 181 to the C state. Simultaneously, the line 217 print mode termination signal flows through OR circuit 218 resetting copy interrupt latch 190 to the zero or noninterrupt state. That is, since copy production machine 10 has been returned to the foreground copy mode, the copy interrupt latch should be in a noninterrupt mode.

AO circuit 186 sets foreground mode latch 181 to the print mode upon completion of the copy interrupt operation, upon receiving a print request over line 187 when the copy mode is inactive or when copy mode (interrupt activated or otherwise) is overridden by operator selection. The copy mode being inactive is indicated by the C state of foreground mode latch 181 and copy interrupt latch 190 being reset and the output of AND circuit 220 indicating that start button 180 has not been actuated when copy mode switch 135 was selected. The Al input portion of AO 186 then responds to a line 187 print request signal to set latch 181 to the P state.

The A2 and A3 input portions reset the copy mode to the print mode upon the termination of a copy selection interruption function. The A2 input portion responds to the duplex indicating signal received over line 196 from CPP 13. The copy interrupt latch active signal received from latch 190 indicating the copy mode was active because of a copy interrupt and the output of timer 208 to set the foreground mode latch 181 to the P state while resetting copy interrupt latch 190 to the noninterrupt state. A3 input portion to AO 186 performs the same function in the simplex mode. Deselection of the copy mode after an interrupt is detected by the A4 input portion of AO 186 for performing the same function. In this regard it may be noted that copy mode selection switch 135 when actuated in the copy mode deselects the copy mode.During a copy mode run switch 135 and start switch 180 are deactivated by circuits not shown. Actuating read switch 155 when the copy mode is the foreground mode (latch 181 is in the C state) actuates the A5 input portion of AO 186 to deselect the copy mode and activate the print mode. The read switch requests LT 16 to read a word processing card from slot 137. Therefore, such request is considered an operator override of copy mode selection, including copy selection interrupt.

Compare circuit 206, which indicates the completion of a print set production, is also used in conjunction with copy production in the copy mode and the indication of the completion of a copy set. A difference between a print set and a copy set is that the print set contains a plurality of images corresponding to one complete set of original documents, while a copy set is a plurality of reproductions of the same image from but one original document. A pair of AND/OR circuits 222 and 223 respectively provide selection and copy count input to compare circuit 206. The Al input portions of AOs 222 gate the signal contents of print select register 205 to compare circuit 206 when foreground mode latch 181 has been set to the P state. Similarly, the Al input portions of AOs 223 gate the signal contents of print counter 203 to compare 206 during the print mode.Similarly, a panel 52 selection indicates to copy production machine 10 the number of copies to be produced in the copy run. Copy select register 224 memorizes the selection and supplies its signal contents through the A2 input portions of AOs 222 during the copy mode. Similarly, copy counter 225 counts the copies during the copy mode and supplies such copy count through the A2 input portions of AOs 223 to compare 206. Compare circuits 206 operate identically in both the print and copy modes.

The A2 input portions of AOs 222, 223 respond to the C state of foreground mode latch 181 for passing the above-described signals. Further, AND circuits 226, 227 respond respectively to the P and C states of latch 181 to pass the copy count indicating signals supplied over line 228 by CPP 13 to counters 203 and 225, respectively. Operation of these circuits is well known and not further described.

Further, during the interrupt signal on line 191 may go to CPP 13 for inhibiting further paper picking until completion of print mode selection.

In a constructed embodiment of the invention it is preferred that the logic of operations illustrated in Figure 13 be performed by microcode in SMP 62 and CMP 170. In this regard SMP 62 contains programming corresponding to the operation of set control circuits 210, 215, 216, foreground mode latch 181, copy interrupt latch 190, as well as mode selections. CMP 170 contains programming for performing the functions represented by circuit elements 205, 224, 222, 206, 223, 203 and 225. Jam circuits 200 are preferably primarily known hardware circuits for performing the detection and jam control functions. With respect to jam recovery and job recovery it is preferred that the computer programming in SMP 62 cooperate with the computer programming in CMP 170 for effecting a complete job recovery. Such job recovery techniques are beyond the scope of the present description.Programming required to effect a programmed constructed embodiment of the present invention is believed to be well within the skill of the ordinary programmer who can understand the logical operations described with respect to Figure 13. Such combination of programming and response of computer circuits to such computer programming or the illustrated hardware logic circuits is couched in terms of means plus a function in several of the apparatus claims.

Image-Indicating Signal Source Selection and Control Figure 14 illustrated circuits show the logic of selection between local terminal LT 16 and remote terminal connector 17 as image sources for image generator 12C which is a portion of the laser input 12B. Text signal flow can come from the remote terminal connector 17, illustrated in Figure 14 as a modem 17M. The signals from modem 17M are text processed at 62T which is a symbolic representation of the text processing computer programs (not shown) residing in ROS (could be a RAM) control store 63, for example, or alternatively in page memory 64 and operated upon by SMP 62. The text processed signals are temporarily stored in page memory 64, as previously described. From page memory 64 the text processed signals are transferred to image generator 1 2C for generating images on copy sheets as described above. The text processed signals in page memory 64 are also transferred under SMP 62 control to nonvolatile store 19 for use in production of the second and subsequent print sets. Similarly, local terminal 16 is shown in Figure 14 as magnetic card recorder/reader 16M. Signals from recorder/reader 16M are text processed at 62T and thereafter treated within copy production machine 10 the same as those image indicating signals, or text signals received via modem 17M.

The signals in recorder/reader 16M are generally generated in the same physical proximity with copy production machine 10, no limitation thereto intended. That is, a word processing apparatus 16P includes a word processing station 16PA which includes a typewriter, a memory for storing text or word processing signals, and associated control circuits, such as used in the Magnetic Card Selectric Typewriter Model II produced by International Business Machines Corporation, Armonk, New York.Also in apparatus 16P is a magnetic card recorder/reader 16PB. Magnetic cards are recorded under control of the word processing station 16PA by recorder/reader 16PB. Once the cards are recorded which includes recording a top or a lead card for the OCL signals, the cards are manually transferred, as indicated by the double-headed arrow 230, to recorder/reader 16M by inserting same in slot 137 (Figure IB). Reader 16M then reads the previously recorded text signals and supplies same to page memory 64 as previously described as image indicating signal. Similarly, recorder/reader 16M may receive text processed signals via logic step 62T for recording same on magnetic cards.Magnetic cards are then transferred to the recorder/reader 16PB as indicated by double-headed arrow 230 for reproduction at word processing station 16PA. Further, signals received via modem 17M can be text processed by copy production machine 10 and then recorded on magnetic card recorder/reader 16M, cards transferred as indicated by double-headed arrow 230 for operation by word processing station 16PA or for storage in a central file in a copy production room (not shown). Also, it should be noted that the received signals recorded on recorder/reader 16M can also be supplied to image generator 12C for copy production.

It is apparent because of the serial path including items 62T, 64, 12C that either but not both modem 17M and reader/recorder 16M can be used at a given time. As constructed, in the illustrated copy production machine 10, receipt of signals by copy production machine 10 is alternated on a job group basis between modem 17M and reader 16M. Control is effected by local-remote latch 231 which activates modem 17M in the remote or R signal state and reader/recorder 16M in the local or L signal state. Switching between the L and R states is under control of a timing pulse received over line 232 from clock 75 and hence is asynchronous with respect to the operation of CPP 13. A pair of latches 233, 234 respectively indicate whether the local or remote image sources are active.When both latches 233, 234 are in the I state (inactive) neither image source is receiving signals. Only one of the two latches 233, 234 can be in the A or active state at a given time.

Assume that both image sources are inactive. To select LT 16 the operator actuates read switch 155 on control panel 52. Actuation of switch 155 sets a latch (not shown) which memorizes that a read selection has been made. Cancel switch 244 resets the latch (not shown) deselecting the read selection. Assume that switch 155 has been actuated to supply a read request signal over line 235 signalling magnetic card reader/recorder 1 6M that a read selection has been made.

Recorder/reader 16M responds by turning on certain motors and doing some automatic preparatory steps for reading the cards inserted into slot 137 (Figure 1 B).

The line 235 read request signal also goes to AND circuit 236 for setting localremote latch 231 to the L state. The only other requirement for setting local remote latch 231 to the L state is that latch 234 is in the I state. Simultaneously, the line 235 signal also goes to AND circuit 237 for setting local active latch 233 to the A state.

This action is achieved at timing pulse 232 time when latch 234 is in the I state and cards have been inserted into the slot 137. Recorder/reader 16M has a sensing switch 238A sensing the presence of magnetic record cards in slot 137. Line 238 carries the signal indicating that no cards are in slot 137 for resettting local-active latch 233 to the I state. Inverting circuit 240 inverts the hopper or slot empty signal on line 238 for activating AND circuit 237 whenever cards are in slot 137. AND circuit 237 having sensed all of the input conditions are being fulfilled, sets latch 233 to the active state thereby indicating that recorder/reader 16M is to supply image indicating signals as an image source for image generator 12C.

Similarly, remote active latch 234 set to the active or A state whenever local remote latch 231 is in the R state by AND circuit 241. AND circuit 241 responds to the timing pulse on line 232, local active latch 233 being in the I state and a request received over line 242 from modem 17M indicating signals are to be received by telephone line TP to set local remote latch 231 to the R state while simultaneously setting latch 234 to the A state. Latch 234 remains in the A state and local remote latch 231 remains in the R state until signals are received by modem 17M from the communication system indicated by line TP that the communication session has been terminated. Termination of the communication session (job group) is detected by decode circuit 243 responding to a preset condition set by SMP 62 in response to OCL decoded signals.When the proper code has been detected by decode 243 latch 234 is set to the I state freeing copy production machine 10 to receive image signals from recorder/reader 16M.

There are three states of control for decode 243. The first two respectively respond to an EOT (end of transmission) or an ETX (end of text) coded signals received over TP by modem 17M. In response to receiving these signals, when conditioned by the OCL language signals via SMP 62, decode 243 sets the remote active latch to the I state. Until these control signals are received, copy production machine 10 is in the so-called receive mode for receiving signals over line TP.

While Figure 14 shows that decode 243 receives signals directly from modem 17M it is to be understood that the functions of illustrated modem 17M not only include signal communication functions but also text analysis functions which include analysis and decoding of OCL signals. All of the latter two functions are preferably performed by SMP 62 in computer program form hence SMP 62 performs communication related tasks. Therefore decode 243 in a constructed embodiment preferably consists of a computer program routine decoding the received TP line signals.

The third state for OCL control of copy production machine 10 is a so-called dedicated receive mode wherein the OCL signal received over line TP indicate that the communication session is not to be terminated. Accordingly, when a receive mode is established in copy production machine 10 remotely via control signals received over line TP, copy production machine 10 is maintained in the receive mode until manual intervention is achieved at control panel 52 by an operator actuating a cancel button 244 which resets remote active latch 234 to the I state thereby disengaging machine 10 from the dedicated receive mode. OR circuit 245 combines the signals from decode 243 and cancel switch 244 for resetting latch 234.

When either latch 233 or 234 are in the active state, indicating that image indicating signals are to be transferred to image generator 12C, OR circuit 246 passes such active signals to line 187 as a print request signal for AO 186, described with respect to Figure 13. Accordingly, when the OCL language signals received over line TP set decode 243 to a nonterminating condition, latch 234 remains in the A state until cancel button 244 has been received. Therefore, by the OCL programming of document production machine 10 via the OCL control of decode 243, the print mode becomes a programmed "permanent" foreground mode of operation as opposed to the copy mode being the dominant foreground mode. This mode state is maintained irrespective of whether or not CPP 13 is actively producing copies from images supplied by modem 17M.Accordingly, copy production machine 10 can have a foreground mode of convenience copying when in the inactive state or a print mode when in the dedicated receive state. In the latter dedicated receive condition all copy requests result in a copy interrupt of the programmed but inactive print foreground mode.

When in the dedicated receive mode copy production machine 10 can still recognize OCL signals interleaved among signals supplied over line TP for changing the dedicated receive mode to a mode for terminating the communication session by either EOT or ETX; that is, copy production machine 10 can be initially set up at the beginning of a work shift in a dedicated receive mode, then later in the day under remote control, OCL signals can be transferred changing the dedicated receive mode to that of selected communication session termination by EOT or ETX.

From all of the above it is readily seen that the type of controls provided by the present invention in the utilization of CPP 13 for producing copies from diverse image sources results in a maximal utilization of the copy production machine while maintaining convenience copying facilities in a word processing area. While copy production machine has been illustrated as a transfer electrographic copy producer, no limitation thereto is intended. For example, so-called noncontact printing of the ink jet type may be equally employed with success, impact printers may also be used. Further, while the invention has been described in the word processing environment the use of image transfer such as facsimile, i.e., pictures, can be imposed on copy production machine 10 interleaved with text signals, all of the latter being determined by the construction of image generator 12C as well as the programming of MPMC 15 in controlling copy production machine 10.

It should also be noted that the termination of a local image input is based upon slot 137 sensing switch 238A indicating no more cards in recorder/reader 16M. Accordingly, recorder/reader 16M when activated can contain a plurality of actual print jobs and maintain reader/recorder 16M as the image source for image generator 12C throughout a succession of such jobs, that is, for example, four OCL cards may be interposed in slot 137 such that four word processing print jobs can be automatically performed by copy production machine 10 in active succession.

Further, if a print job is being performed by copy production machine 10 and additional cards are added to slot 137, copy production machine 10 will then respond to those newly added cards before allowing modem 17M to receive text signals in a receive mode. Accordingly, remote control of copy production machine 10 via modem 17M can dedicate it to receiving remote image indicating signals whereas the local terminal 16 can also be programmed via the insertion of cards in slot 137 for maintaining a dedicated print mode in copy production machine 10 for receiving locally generated images. On the other hand, recorder/reader 16M and copy production machine 10 may be programmed to respond to detecting an OCL card in slot 137 for sensing whether or not signals are to be received via modem 17M thereby allowing a greater interleaving of images being received locally and remotely.However, it is believed that the arrangement shown in Figure 14 wherein hopper or slot 137 must be empty of cards is a convenient control mechanism for copy production machine 10 in that all local jobs are grouped together in output portion 14B while all remote generated jobs received via modem 17M are also grouped together in output portion 14B. The programming represented by Figure 14 circuits therefore enables job grouping by image sources while enabling convenience copying interruption of those grouped print jobs without interfering with such print functions. Separate output portions can also be provided for each image signal source. Such image sources can be based on image bearing documents, electrical signal sources and the like. Instead of determining a foreground mode and a background mode, when no copies are being produced an IDLE mode can be established.An IDLE mode deselects both copy and print mode, i.e., both copy mode and print mode are background modes.

There may also be more image sources, with an operational mode associated with each source with a hierarchy of interruption levels for copy production. Each image source may or may not have an associated output portion, either dedicated by hardware design or dynamically under program control. A single output portion may be shown by offsetting copies from the various image sources. The copy production interruption may take the form of dynamic interleaving as described above.

In the copy mode the copy production machine operates as any convenience copier; the number of copies are predetermined usually via panel 52. In the print mode the panel 52 selections on the OCL select the number of print sets to be produced. Until the first print set has been printed, the number of pages in a print set are unknown or not registered in copy production machine 10; i.e., a predetermined number of print sets are to be produced, each print set having an indeterminate number of pages. Each print set can be produced without actually counting the pages in each set. Since NVS 19 contains image indicating signals for all pages of a set, CMP 62 merely reads all recorded image-indicating signals for a set to produce a printed set. Of course, billing meter M tallies the number of sheets employed in producing the print set.Counting the number of pages in a set and knowing the number of pages to a set facilitates error recovery, a subject beyond the scope of the present invention.

In the duplex print mode, SMP 62 is preferably programmed so that the number of print set pages is always even. For an odd number of received images (in the physical form of image-indicating signals) an additional page (blank) is added to the odd-numbered page duplex print set. Instead of printing the last image as a blank page, CPP 13 can be constrained in operation so that photoconductor drum 20 receives no toner ink; i.e., CPP 13 operates in a so-called dummy or no transfer cycle for keeping the last page blank.

There is no copy production machine control over the number of pages to be included in a print set. Copy production machine 10 has interim storage unit 40 used in the duplex print mode. The finite capacity of this unit could be executed in any given print set. When this situation arises, the print job is automatically divided into parts determined by the capacity of interim storage unit 40. For example, when interim storage unit 40 has a capacity of 100 sheets, each 500 page (250 sheets) print job for 43 print sets is handled as follows. NVS 19 receives the first 200 pages of the print job as described in steps 121-126 of Figure 9.When 200 images (100 sheets of printing in duplex print mode) have been received, RTC 17 or LT 16, as appropriate, are put in a hold status while LI 12B and CPP 13 print the first 100 sheets of all 43 print sets and supply same to output portion 14B. Then, SMP 62 under program control automatically restarts RTC 17 or LT 16 to receive the next 200 images. Then, RTC 17/LT 16 is again put on hold while LI 12B and CPP 13 supply the next 100 sheets of duplex copies to output portion 14B. The last 50 sheets of 100 images are handled in a like manner, all as shown in Figure 9, except for the automatic job requesting to accommodate limited capacity of copy production machine 10 while automatically performing a complete print job having a requirement exceeding capacity of copy production machine 10.The same technique is employed when NVS 19 fills up with a partial print job imageindicating signals.

In the even blank paper supply 35 becomes empty, all print operations of copy production machine 10 cease. In the print mode it is preferred the receipt of image indicating signals may continue until page memory 64 is filled or 200 images have been received. Alternately, receipt of image indicating signals may also be interrupted.

As stated above, various text parameters are imposed upon copy production machine 10 via OCL. In some instances OCL may not include sufficient parameters for successfully doing a print job. In such an instance document production machine 10 via SMP 62 scans the panel for those parameters insertable by an operator; for example, duplex mode, number of copies, and so forth. If there are no appropriate panel selections then SMP 62 fetches default parameters data from NVS 19. That is, upon initializing document production machine 10 NVS 19 stores so-called default parameters for operation of document production machine 10. In the absence of any parameter selection, these stored default parameters are fetched by SMP 62 and inserted for text processing purposes and subsequent printing of copies.Accordingly, the parameter selection hierarchy is OCL first, panel second (limited selections), and finally default parameters stored in NVS 19.

Further, a plurality of default sets may be stored on NVS 19. For example, it may be desirable to have a first set of default parameters for signals received over the communication line via RTC 17, and a second set of default Parameters for the word processing input from LT 16. Other variations on selection of text processing parameters can be easily envisioned. Of course, when the panel is being; used in an active copy mode, the panel is disregarded.

The interruption of the print mode by the copy mode and vice versa illustrates dynamic interleaving of image sources for producing diverse copies of the copy and print type with a single CPP 13. As described for a constructed embodiment, a photoconductor drum 20 has a pair of image areas for transferring images to copy sheets. When interrupting the print mode, the copy mode has exclusive use of the image areas. No such limitation thereto is intended. For example, depending upon the characteristics of the automatic image sources, i.e., RTC 17 and LT 16, it may be desirable to limit the number of copies made in a given copy mode run, such as not to delay operation of the image sources in an unduly manner. Primarily, cost considerations will affect this decision.Accordingly, in a print mode that is interruptible by a copy mode, the copy mode functions can be dynamically interleaved with print mode functions on a one out of two image area basis, one out of four image area basis, and so forth. Such is particularly easily implemented in a belt type of xerographic reproduction section CPP 13 wherein, for example, seven image areas on a belt. In such a case, one, two, or more displaced or adjacent image areas may be intermittently or repeatedly assigned the copy mode upon receiving a copy mode interrupt request. In any event, many instances may require a judicious balancing between copy mode operations and print mode operations. Ina broader sense, images received from diverse image sources are dynamically interleaved in a single CPP 13 and supplied to the similar diverse output portions.Of course, in all these dynamic interleaving design decisions jam recovery aspects must be fully considered.

The number and types of image sources that can be used with the present invention are substantially unlimited. The constructed embodiment combine an optical image source with an electrical image source. Image sources may all optical such as that provided by a semiautomatic document feed 11, plus a manual feed (not shown), a semiautomatic document feed and an automatic document feed which supplies successive originals from a stack of documents to be reproduced.

Alternatively, the image sources may be all electronic. For example, the SADF 11 may be replaced by an electrical scanning system which scans a document to be reproduced and produces noncoded information signals which then, in turn, are supplied to LI 12 for operation as aforedescribed when in a facsimile mode.

Further, word processing and analog (facsimile) signals may be dynamically interleaved as well, the latter being determined by the characteristics of LI 12, the details of which are beyond the present description.

WHAT WE CLAIM IS: 1. A copy production machine comprising a copy generator system for producing copies from original documents or from input digital data signals and including a control system for controlling the machine automatically to produce copy runs of one or more copies from an original document or from each of a series of original documents, fed to the machine, said control system being responsive to digital data control signals to cause interruptions in a run of copies from input digital data signals and to control the machine to produce copies from an original document or from each of a series of original documents during said interruptions.

2. A machine as claimed in claim 1 including means, under control of said control system, for directing copies produced from original documents and copies produced from input digital data into separate copy receivers.

3. A machine as claimed in claim 1 or claim 2 including a store for storing input digital data, a character generator arranged to generate character-representing signals from the stored signals, means for assembling the character-representing signals in image groups, in which said control system is responsive to a control signal indicating an assembled image group to initiate the production of a copy or copies corresponding to the assembled image group.

4. A machine as claimed in claim 3 in which said means for assembling' includes means for arranging the characters in groups such as to form collated sets of copies from the digital signals.

5. A machine as claimed in any of the previous claims including collation means for collating copies formed from original documents into collated sets.

6. A machine as claimed in any of the previous claims including means for storing partially completed copies for return to the copy generation system for completion, in which the control system includes means inhibiting said interruption whilst copies are so stored.

7. A machine as claimed in any of the previous claims in which said copy generation system comprises a xerographic system.

8. A copy production machine comprising a copy generator for producing copies from original documents or from input digital signals and including a control system for controlling the machine automatically to produce copy runs of one or more copies from an original document, or from each of a series of original documents fed to the machine or from input digital signals, said control system being responsive to digital control signals to interrupt a multiple copy run, to initiate a further copy run, and thereafter, at the end of the further copy run, or upon interruption thereof, to continue said first-mentioned multiple copy run.

9. A copy production system substantially as described herein with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. interleaved as well, the latter being determined by the characteristics of LI 12, the details of which are beyond the present description. WHAT WE CLAIM IS:

1. A copy production machine comprising a copy generator system for producing copies from original documents or from input digital data signals and including a control system for controlling the machine automatically to produce copy runs of one or more copies from an original document or from each of a series of original documents, fed to the machine, said control system being responsive to digital data control signals to cause interruptions in a run of copies from input digital data signals and to control the machine to produce copies from an original document or from each of a series of original documents during said interruptions.

2. A machine as claimed in claim 1 including means, under control of said control system, for directing copies produced from original documents and copies produced from input digital data into separate copy receivers.

3. A machine as claimed in claim 1 or claim 2 including a store for storing input digital data, a character generator arranged to generate character-representing signals from the stored signals, means for assembling the character-representing signals in image groups, in which said control system is responsive to a control signal indicating an assembled image group to initiate the production of a copy or copies corresponding to the assembled image group.

4. A machine as claimed in claim 3 in which said means for assembling' includes means for arranging the characters in groups such as to form collated sets of copies from the digital signals.

5. A machine as claimed in any of the previous claims including collation means for collating copies formed from original documents into collated sets.

6. A machine as claimed in any of the previous claims including means for storing partially completed copies for return to the copy generation system for completion, in which the control system includes means inhibiting said interruption whilst copies are so stored.

7. A machine as claimed in any of the previous claims in which said copy generation system comprises a xerographic system.

8. A copy production machine comprising a copy generator for producing copies from original documents or from input digital signals and including a control system for controlling the machine automatically to produce copy runs of one or more copies from an original document, or from each of a series of original documents fed to the machine or from input digital signals, said control system being responsive to digital control signals to interrupt a multiple copy run, to initiate a further copy run, and thereafter, at the end of the further copy run, or upon interruption thereof, to continue said first-mentioned multiple copy run.

9. A copy production system substantially as described herein with reference to the accompanying drawings.