JPS58117036A - Print controller - Google Patents

Abstract

PURPOSE:To output data to a print head continuously without interrupting the reception of external print data, by providing two-line's share of buffer memory and using one for printing and the other for a transfer buffer from external devices. CONSTITUTION:A print control circuit 5 outputs a dot matrix data to a character code at each character and an interruption signal 11 informs the end of print of one character to a CPU2 immediately and the next character data is requested. When a printer 7 prints one character, the time is enough shorter than the required time to set the next character data by the CPU2, then the character codes of the next line is inputted externally in the rest time and the data is stored in the other buffer memory not used for the print at the time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a print control device, and more particularly to a print data output control device in a serial dot matrix printer.

Conventional serial dot matrix printers are equipped with a buffer memory that stores multiple character codes, and the character codes transferred from outside are stored in the buffer memory.
When the memory is filled, interrupt external input,
The dot patterns corresponding to the character codes read from the buffer memory are sequentially accessed by the preprocessor and output to the printer for printing. After that, when the buffer memory becomes empty, the character code is again stored externally in the buffer memory.
In dot matrix printers, such as charge-controlled inkjet printers, it is necessary to continuously output t-1 lines of dot matrix data of characters, and printing cannot be interrupted character by character due to external circumstances. .

Therefore, it is equipped with a buffer memory with a capacity for the maximum number of prints per line, and when the buffer memory is filled with print data for one line, the dot matrix data corresponding to the character code is transferred from the beginning of the line. A method is adopted in which all patterns are read from memory and sequentially output to a printer. However, with this method, reception of external print data σ) must be interrupted while printer print matrix data is being output.

On the other hand, in a serial dot matrix printer in which the print head can stop at any position, a character code register 't- is provided, a character hood transferred from the outside is set in that register, and the character code and address of the register are set. - The character pattern memory is accessed by a counter, and the dot pattern is sequentially output to the printer at one character position.

Then, when one character is completed, the print head is stopped,
Insert the next character hood to be printed from outside, set it in the character code register again, and repeat printing.

In this case, the interruption time is long because the printing is about one character, but the dot matrix data is still output to the printer, and while the printer is printing, the reception of print data from the outside is interrupted. I have to do it.

An object of the present invention is to eliminate such conventional drawbacks by continuously transmitting dot matrix data to a print head that is required to run at a constant speed without interrupting the reception of print data from the outside. An object of the present invention is to provide a print control device for a serial dot matrix printer that is capable of outputting
, a pattern memory for storing a dot matrix pattern of a character corresponding to a character code, a register providing a storage address for the pattern memory, and an address counter for generating an address within one character of a character pattern for each character. In serial dot matrix printers with
A register, a pair with each address register, a pattern size register indicating the size of the character pattern, and an acid pattern size register value and the above address register.
The present invention is characterized by providing a comparator that performs a sound comparison of the counters and obtains a -tone signal, and means for selecting and specifying one pair from the plurality of pairs of address registers and character size registers as a match signal t-click. .

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a driver) and a pattern/address configuration of a printer to which the present invention is applied.

The dot matrix can be accessed in units of 8 piF.
Assume that it is stored in OM. The character (W) shown in FIG. 1(a) is composed of 32 x 32 dots (128 bytes), and 32 dots (1st to 4th bytes) form one main scanning line from the bottom left upwards. When one main scan is completed, the second main scan is repeated from bottom to top.

Therefore, the ROM (character pattern memory) has
The data is stored sequentially from the main scanning direction as 4 bytes per main scanning direction, and when read out, 32 lines in the main scanning direction are read out in the same order in the sub-scanning direction.

Next, the character pattern Atrea is the first [ff1(b
), for example, it is composed of the upper 7 bits and the lower 7 bits, and the upper 7 bits are the characters (1
28 characters/phone)) t-J%, the lower 7 bits are 1
Specify character dot/matrix data (128 bytes/character).

FIG. 2 is a block diagram of the entire printing control section of a printer to which the present invention is applied.

The maximum number of prints for one line in the printer is predetermined, and a buffer for two lines is logically provided in the memory 4. One of these buffer memories is used for printing, and the other is used as a transfer buffer from the outside (such as a host computer).

Currently, character data (character code, control code *
) 9 is transferred, the interface unit 1 notifies the processor (hereinafter referred to as 0PU) 2 with an interrupt signal 10.

The 0PtF2 stores the transferred character data in one buffer memory in the work memory 4 via the bus 8, but at that time it converts the character code in the code conversion table in the program memory 3. There are two ways to store the character code in the buffer memory after converting it to the corresponding address and character pattern size in the character pattern memory, and to store the character code as it is in the buffer memory, which will be described later. There is a method of converting the data into a corresponding address and character pattern size and setting it in the DMA circuit 6, and any method may be used.

When one line of character data is stored in the buffer memory, 0Ptr2 issues a print command to the printer via the printer control register 6.

The control register 6 controls the feeding of printing paper and the carriage.
It is provided for controlling return, carriage scanning instructions, etc. Before starting carriage scanning, optr2 operates a print control circuit (hereinafter referred to as DM circuit) δ according to the present invention.
It is necessary to set the character information (R0M address, character size) corresponding to the first and second character codes to be printed on the printer, and when the carriage starts scanning, it is synchronized with the clock 13 from the printer 7. and output the dot matrix data 12't to a printer.

The DMA circuit 5 outputs all the dot matrix data corresponding to the character code for each character, and as soon as printing of one character is completed, it notifies the optr 2 by an interrupt signal 11 and requests the next character data.

The time the printer is printing one character is 0ptr2
Since the time required to set the next character data is sufficiently longer than the time required to set the next character data, the character code for the next line can be entered from outside in the remaining time, and the character code used for printing at that point can be inputted from outside. data is stored in the other buffer memory.

In this way, by alternately using two sets of buffer memories (as a print buffer and an input buffer), it is possible to input character codes continuously from the outside.

FIG. 3 is a block diagram of a print control circuit showing an embodiment of the present invention.

In the present invention, character address registers 21.22, character size registers 23.24 and r
Address counter value and character size register 23 and 24 that provide w number of sets and read the character dot matrix
A comparator 26 that compares all values with the value of
rW/, a character dot matrix is continuously output to a printer having a head running at a constant speed.

Address registers 21, 22 . font size·
Registers 23 and 24 are assigned as output registers of OFυ2, and character information (address, character size) is passed through bus 8 to register write signals 41, 42, and 4.
Set by 3.44. That is, the character data to be printed (the storage address of the character dot matrix memory 25 corresponding to the character code) is set in the address register 21 of Na1, and the character data to be printed is set in the character size register 23 of Na1. Character size (character dot matrix memory 2δ corresponding to character code)
matrix size) is set. Furthermore, the character data to be printed first is set in the address register 22 of Na2, and the size of the character pattern to be printed next is set in the character size register 24 of Na2.

As mentioned above, the character data and character size conversion table for character codes is stored in the program memory δ, and the character data input from the outside by OPH1 is stored as is in one buffer memory in the work memory 4. If so, start up the oytr2#DMλ circuit 5, convert the character code into the storage address of the character pattern memory and the size of the character pattern by a program, and send the converted data via lines 41 to 44]) It can also be set in each register of the MM circuit 6. Then, while the printer is performing a printing operation, 0Pty2 sequentially stores manual character data from the outside into the other buffer memory of work memory 4 via bus 8.

In FIG. 3, the address register number 1 contains the top seven characters in the dot matrix memory of the first character to be printed.
F less is set, and the tod matrix memory 25 is accessed by the upper address specified by the address register φ1 and the lower address specified by the address counter 30. In synchronization with the click (OZX) from the serial dot matrix printer,
In order to output the dot matrix data (b) as serial data in the main scanning direction, the shift register 28
is provided. In other words, the character dot matrix
From the memo 925, set the accessed parallel data in the shift register 28 and transfer it to the
) and output as serial data ((9)).

Each time the contents of the shift register 28 change, a carry signal 33 is output from the pixel counter 29, and this carry signal 33 loads the next parallel data into the shift register 28, and the address counter 30t is incremented to set the address. Update. This address
The value of counter 30 is the character dot matrix memory 2.
6 as a lower address, and is sequentially specified within the maximum number of bytes that make up one character, 128 bytes, and serves as one input to the comparator 26. Comparator 26 and character size registers 23 and 24 are The character width differs depending on the size (for example, 24 lines for 1/10 inch width, 20 lines for 1/12 inch width, 16 lines for 1716 inch width, 12 to 32 lines for square space characters) , each 7-ont-sized to control the character width.

At the other input of comparator 26, character size register 23
．． 24 is switched and input, so each time the value of the address counter 30 is updated, the character size registers 23 or 24 are compared, and the last value of the character is It is determined that this is a byte access.

Address registers 21, 22 and 2
The character size registers 23.2 of , and 2 each have a tristate output structure and are wired-OR connected.

1-character dora) v) When the risk range ends, the match output from the comparator 26 is sent to the 7-lip/70-tub flop 27 for register specification, and the setting/reset of this 7-lip/70-tub 27 is switched. Accordingly, either one of address registers 21 and 22 and character size registers 23 and 24 can be switched by a set or reset signal.

On the other hand, the comparison signal clears the address counter 30 and at the same time becomes an interrupt signal 11 which sets the next character data and character size to 0PU2.

The reason why two sets of address registers and two character size registers are provided is that the character data is set by a program using the operation t-OF'U2.
This is because the printing characters are switched in real time because it takes a certain amount of time and data output to the printer 7 cannot be made to wait during that time.

As explained above, according to the present invention, address registers twI of the dot matrix memory are provided every time, and the conversion t-1 from character code to dot matrix data is performed.
Since it can be performed continuously for each character, it can be used for serial, dot matrix, and printhead printheads that require constant speed running.
It becomes possible to continuously output data to the printer, and it is also possible to receive print data from the outside without interruption.

[Brief explanation of drawings]

Diagram 1 is a configuration diagram of the dot matrix and pattern address of the printer using the present invention, and Figure 2 is a block diagram of the entire print $1 control unit of the printer using the present invention.
FIG. 3 is a block diagram of a print control circuit showing an embodiment of the present invention. σ l: interface, 2: OPU, 3 nibs, 4 duram memory, 4: work memory, 5: print control circuit (D
MM circuit), 6: Control register, 71 Serial dot matrix printer, 21. 22 Near address register, 23. 24: Character size register, 25: Character dot! ) risk memory, 26: comparator, 27: 7 rip 70 registers, 28 digital registers, 29: [element counter, 30 near address counter. For patents - Dai Rico Co., Ltd. - Agent Patent attorney Masatoshi Isomura: ]. ,・(',・. Figure 1 (a) □ Sub-scanning direction 32 lines (b) 1- position Do position 7bτ 7bτ

Claims (1)

[Claims] A pattern memory that stores a character dot matrix corresponding to a character code, a register that indicates a storage address of the pattern memory, and an address that generates an address within one character of each character pattern. In a serial dot matrix printer having a counter, a plurality of registers indicating the storage address of the character pattern memory; a second register forming a pair with each register and indicating the size of the character pattern; , a comparator that compares the value of the designated second register with the value of the address counter and provides a match signal, and uses the match signal as a cross-reference signal to select one of the first and second registers of the plurality of pairs. 19# [Printing control device characterized by being provided with a means for selective operation.