JPS59176843A - Microprogram control system - Google Patents

Abstract

PURPOSE:To improve the correcting efficiency of a program when the specification is changed or a fault arises by transferring a main program for control to an RAM, then reading the program out of the corresponding RAM to execute it. CONSTITUTION:When a computer main body device is actuated, a main program in an ROM5 is shifted to an RAM10 and the control is jumped to a program written to the RAM10. The control of the main body device is carried out by reading the program of the RAM10 through an MPU6. In this case, the main program of the ROM5 is not executed. When a correction command is given from the main body device during execution of the RAM program, a new statement is written to an indicated address within the area of the RAM10. When a data reference command is given from the main body device, the reference data is sent to the computer main body device.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a control system for controlling output devices, input devices, and other peripheral terminal devices of an electronic door machine using a microprogram.

・Technical background Most of the current electronic tl' computer peripheral terminal devices are controlled by a microprogram system, and are equipped with a read-only memory (J: J, abbreviated as ``ROMl'' below and in the claims. ) is controlled by a microprocessor executing a control program written in advance.In such peripheral terminal devices, changes in control operations due to changes in specifications, etc. are realized by changing the control program.

- Prior art and interlayer points In the conventional microprogram control system for computer peripheral terminal devices, the program was directly read from the ROM by the microprocessor and executed. Therefore, when the control specifications of the device change or a failure occurs, it becomes necessary to change the program stored in the ROM, and the ROM in question must be removed from the device and the modified program is written to the ROM writer. A complicated procedure of writing and re-installing ROλ1 into the device was required. Maruko,
When developing peripheral terminal devices or changing specifications, when a failure occurs, it is necessary to write each program to ROM and try to operate the device in order to check the operation of the developed or modified program. Program development and debugging required a large amount of time.

-Purpose of the Invention The present invention was made with the aim of solving the problems of the conventional means described above, and it is possible to modify and execute the control microprogram written in the ROM online from the main unit. By providing a possible microprogram control method, it is possible to perform control program development work, program modification work in the event of specification changes or failures in an efficient manner, and program modification commands can be issued from the main unit at startup. This was done with the aim of making it possible to control devices whose specifications have been changed without rewriting the ROM, in the event that there is a slight change in the control specifications of the peripheral terminal device fat, by always giving be.

・Structure of the invention In order to achieve the above-mentioned purpose, the method of the present invention uses the conventional RO
The control program that was directly read from M and executed by the microprocessor is once transferred to a read/write memory (hereinafter referred to as rRA MJ in the claims) and then read and executed by the microprocessor. There is. RIJ, the microprogram control system of the present invention is an operation control system for an electronic divider peripheral terminal device that is controlled based on a program written in a ROM. A program area is provided in the ROM, and a routine is added to the program in the ROM to accept the initial control program and microprogram modification or reference commands sent from the computer main unit. The program is such that the main program in the ROM is transferred to the RAM, and control is jumped from the final step of the initial control program to the main program transferred to the RAM. When an online program modification command or data reference command is issued from the computer main unit, the command is accepted by a routine, making it possible to freely modify or refer to the program or data in the RAM. It is something.

Embodiment Next, an embodiment in which the method of the present invention is applied to a serial printer will be described based on the drawings.

FIG. 1 is a diagram showing the hardware configuration of the device, and M P
U indicates a microprogrammer, numeral 1 indicates a print head, 2 indicates a motor, 3 indicates a rock structure of the printer, and 4 indicates a printer control section. The printer is controlled by the microprogram by the MPU 6 reading out and executing the microprogram written in the ROM 5, and using the print data given from the divider body 8 through the interface circuit 7 and the printing surface given from the sensor 9. j
? ``Depending on the state of section 3, motor 2 and print mode 1
The printing operation is performed by driving the . RAM 106 is
This RAM is also provided as a print data buffer in conventional devices, but in the method of the present invention, this RAM
Add an area and provide a program area within the RA hi.

Figure 2 is a flowchart showing a conventional control method.In the conventional method, after inputting the m-e of the device, an error check is performed by vertical)+return or vertical addition of the program written in the ROM. After that, the control program is directly read from the ROM and executed. In the figure, FRO
MROM program j means the program written in ROO12.

On the other hand, in the method of the present invention shown in FIG. 3, when the device is started up, the ROM program is thoroughly checked in step 11 as in the conventional method, and the main program part of the ROM program is transferred to RAλ1 in step 12. move it. Then, in step 13, the main program moved to the RAM is checked again, and in step 14, control is transferred to the RAM.
^1 Jump to the program. Here, the term "rRAM program" means the program loaded into the RAM in step 12. The device is controlled by the MPU reading and executing the program in the RAM in step 15, and the main program in the ROM is not directly executed. The MPU controls printing based on instructions from the main unit, self-test printing, and operations using the paper feed switch, using programs written in the RAM. If a program modification command is input from the divider main unit while this RAM program is being executed, this command is accepted in step 16 and the control flow branches to step 17, where a new command is entered at the specified address in the RAM area. Popularize the statement. Also, when a data reference command is received from the main unit,
This command is accepted by step IJ, and the control flow branches to step 19 to send the referenced data to the subtraction machine main unit. In the embodiment shown in FIG.
Steps 11 to 14 are initial system a (1 program), and steps 16 to 19 are routines for accepting microprogram modification or reference commands sent from the subtracter main unit.
This is a routine included in the main program transferred from OM to R'AM.

FIG. 4 is a block diagram schematically showing the operation of the initial control program shown in steps 11 to 14 in FIG. 3, and the initial control program 20. A main program 21 and check data 22 and 23 are included. In step 11 described above, the contents of the initial control program 2o and the main program 21 are checked by vertical parity or vertical addition with reference to the check data 22.23, and the main program 21 in the ffiROM is divided into 9 elements in 1-bit units. The data is transferred to a program area of RAM consisting of. At this time, a parity bit is added to each byte of the main program 21 by the parity bit generator 24, and the data is converted into 9 bits and transferred to the RAM. After all the main programs 21 are transferred to the RAM, the check data 23 is used to check errors using vertical parity or vertical addition for the transferred programs.
, control jumps from the last address of the initial control program 20 to the first address of the main program written in the RAM, and control is transferred to the RAM.

Currently, IC memory is I x 641 (bit or l x 2
56 bits and inexpensive dynamic R and AM are provided, while ROM is 8 x 8 bits and 8 x 1 bits.
The mainstream is 6K bits, which is the largest byte. For this reason, when trying to add parity bits to data byte by byte, in the case of RAM, 1 bit for every 8 bits is added.
It is sufficient to add RAM M2S for parity of R
In the case of OM, in the worst case, one ROM for parity is required for each ROM and M, resulting in a lot of wasted equipment installation. However, according to the method of the present invention, as shown in FIG.
When transferring from OO12 to RAM, a parity bit is added to each byte, and the vertical parity or vertical addition result of the program in ffl RAM after the transfer is transferred to RO.
Once the check data 23 of M is checked to confirm that there are no errors, the main control program can be run while being parity-checked after that, making it possible to realize highly reliable control without malfunctions at low cost. There is.

In addition, if there is sufficient storage space or communication lines on the computer main unit, and offline operations such as self-test functions of peripheral terminal devices are not required, the main program for control may be stored in the main unit storage device (for example, a magnetic disk). By storing the program and writing the program into the RAM of the peripheral terminal device using a program modification command from the main unit, the ROM capacity of the peripheral terminal device can be reduced and the cost of the device can be reduced. It also has some characteristics.

- As described in detail, the microprogram control method of the present invention is such that the main program for control is transferred to the RAM, and then the program is read out from the RAM and executed. It becomes possible to freely modify the program during execution or refer to the program data by the subtracter itself, making it easy to change and refer to microprograms for controlling peripheral devices, greatly improving maintainability. In addition, it becomes extremely easy to check program operation and debug when developing a device or changing specifications, and the number of man-hours required when developing or modifying a program can be significantly reduced. In addition, when changing the control specifications or adding optional operations, there is an advantage that control can be performed using modification commands from the subtraction machine main unit without modifying the RO'M program. . In addition, since the microprogram itself has the ability to rewrite itself in response to input boat signals, operator instructions from the console, or commands from the computer main unit, it is more flexible in program creation than when directly controlled by a ROM program. can significantly increase the performance. Furthermore, for the reasons mentioned above, the memory elements can be used efficiently, and control can be realized at low cost and with high reliability.

[Brief explanation of drawings]

Figures 1, 3, and 4 are diagrams showing one embodiment of the present invention. Figure 1 is a block diagram showing the hardware configuration, and Figure 3 is a block diagram showing the hardware configuration.
Figure 4 is a flowchart showing the control procedure, Figure 4 is a block diagram showing the flow of data during program transfer, and Figure 4 is a block diagram showing the flow of data during program transfer.
The figure is a flowchart showing a conventional control method. In the figure, 3 is a mechanical unit, 4 is a control unit, 16 to 19 are routines for receiving commands, 20 is an initial control program, 21 is a main program, 22 and 23 are check data, 24 is a parity bit generator, and 25 is a parity This is RAM for Agent Patent Attorney Takashi Nishi 1; Figure 2 Figure 3, Figure 4 ROM AM Bit x 9

Claims (1)

[Claims] (1) In the operation control method of the electronic i1' computer peripheral device 6 which is controlled based on a microprogram written in a ROM, a program area is provided in a RAM connected to a bus common to the ROM. In addition, a routine is added to the program in the ROM to accept the initial control program and microprogram modification or reference commands sent from the computer main unit, and when the peripheral terminal device is started, this initial control program is stored in the ROM. A microprogram control method characterized in that after a main program is transferred to a RAM, control is transferred to a program in the transferred RAM area.