JPH082024A - Printer - Google Patents

Abstract

PURPOSE:To shortening depiction processing time by selecting the maximum bank number among ones that are smaller than time depiction address every character or graphic of printing information, and controlling the bank address regarding the address of a frame memory corresponding to this as a head address for effecting depiction. CONSTITUTION:The serial interface 41 receives command signals from the host computer and then stores them into the receiving buffer 5 and activates a PC application task (PC task) 42. The PC task 42 acts to edition analyze commands, and write the results down in command cues 44-47 every ink ribbon color. The depiction and print controlling task 43 reads command data from the command cures 44-47 and effects a bank switching operation of the frame buffer 6 by a bank switching process 48. The depiction utility 49 is called out for processing depiction in each depiction area of the frame buffer 6 every printing color.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer having a frame memory capable of forming a plurality of banks, drawing print information for each bank of the frame memory, and calling the drawing data for each bank to print on a sheet. Regarding

[0002]

2. Description of the Related Art Generally, in a printer, for example, a label printer, the length of one label in the scanning direction (paper transport direction) can be printed, for example, from 680 to 1000 mm.

By the way, a 16-bit CPU (central pro
In the case of a cessing unit (not shown), the address of the memory of the entire device is managed by one memory map, as described below.

FIG. 6 is a diagram showing the configuration of the entire memory map.

In the area of addresses 0 to 10000, the CP
A work RAM (random access memory) 101, in which areas of various memories used by U for processing are formed, is allocated, and data obtained by backing up by a battery or the like is allocated to an area of addresses 10000 to 20000. A backup SRAM 102 in which is stored is assigned.

A frame buffer 103 composed of a dynamic random access memory (DRAM) is allocated to the area of addresses 40,000 to 50,000. The actual allocation is designated by the frame buffer 6. One bank (1 segment = 6
4 kbytes) only. That is, in the frame buffer 6, the bank number. A plurality of banks identified by are set. Is designated, the bank assigned to the area of the addresses 4000 to 5000 is switched to manage the entire memory area of the frame buffer 103.

A program area 104 including a memory such as a ROM (read only memory) is assigned to the area from a predetermined address to FFFFF.

As described above, while a label of 680 to 1000 mm can be printed, only one segment is allocated as a frame buffer in the memory map of the CPU, so one bank can store image data of one label. It may not be possible to draw all.

In such a case, the image data of one label is drawn over two or more banks. Further, as the print quality is improved, the head density of the print head is increased, the memory capacity required for the frame buffer is increased, and the image data of one label is spread over more banks. Is drawn.

Therefore, when a 16 Mbits DRAM is used as the memory for the frame buffer, 1 bank = 1 segment = 64 as in the above example.
Bank No. as kbyte. 0 to bank No. 32 banks up to 32 will be formed.

For example, the width of the thermal head is 6 inch (=
If the density is 12 dots / mm at about 15 cm),
One line of the thermal head is about 180 dots 6
If it is 4 Kbytes, it will be 64000/180 = about 356 lines, and if this line is 12 lines per 1 mm, the number of lines for about 30 mm will be one bank.

For example, in the case of the label printing example shown in FIG.
The bank N of the frame buffer 103 of FIG. 6 described above
o. 0 to bank No. Image data for one sheet is drawn over the area up to 4.

This is divided into 64 kbytes in order from the start address of the DRAM in advance, and the bank number is divided into each.
0 to bank No. As 31, a bank is fixedly formed. When drawing, the bank No. Is specified and the image data to be drawn is drawn.

For example, in the frame buffer 103 shown in FIG. By designating 0, the image data of the number "1230" is drawn. Next, bank No. Specify 1 and draw the image data of “A” and “(upper half of W)”. Next, bank No. Specify 2 and draw the image data of "(lower half of W)". Next is Bank N
o. Specify 3 and draw the image data of the barcode.

The dotted line in FIG. 7 shows the bank switching point, and is not the actual printing.

[0016]

As described above, since the bank of the frame buffer in the conventional printer is fixedly formed for each segment in order from the start address of the memory (for example, DRAM), the structure shown in FIG. , The image data of the character "A" can be drawn in one bank, but the image data of the character "W" is drawn in two banks.

In the case where the image data of the character "W" spans two banks, the bank No. 1 and bank No. Drawing will be performed while switching to 2.

For example, an Intel CPU 80186,
CPU clock 12MHz, RAM access 2WAIT, I /
Considering the condition of O output 2 WAIT, the number of soft steps required for bank switching is PUSH DX ... 10 clocks, MOV DX, BANKR ... 4 clocks, MOV AL, bank No. 10 clocks, OUT DX, AL ... 8 clocks, POP DX ... 8 clocks, a total of 40 clocks are required, and the time required for one bank switching is about 4.0 μs.

Therefore, there is a problem in that when the image data that extends over a plurality of banks is drawn while the banks are switched, the drawing processing time is extended by the time required for the bank switching.

Some color printers such as those having a plurality of print heads are provided with a frame buffer corresponding to each print head, and bank switching is further increased when drawing is performed in each frame buffer. There is a possibility that the drawing processing time becomes longer.

Furthermore, an 8-bit CPU or a 4-bit CPU
Since the memory map that can manage addresses is small,
The capacity allocated as the frame buffer is reduced, and the memory capacity per bank is also reduced. As a result, image data is more likely to be drawn over two or more banks. That is, there is a problem that the number of bank switching is further increased and the drawing processing time is lengthened.

Therefore, it is an object of the present invention to provide a printer which can reduce the number of times of bank switching in drawing and therefore can shorten the drawing processing time.

[0023]

The present invention is provided with a frame memory capable of forming a plurality of banks each having a preset number of bytes, and drawing print information for each bank formed in the frame memory. In the printer that calls the specified data and prints on the paper, set the bank number in a predetermined byte unit in the address of the frame memory, and for each character or graphic of the print information, the largest bank among those smaller than the drawing address. A bank number selecting means for selecting a number, a bank forming means for controlling a bank address with a frame memory address corresponding to the bank number selected by the bank number selecting means as a start address, and a bank forming means for controlling the bank address. The drawing is performed based on the address.

[0024]

In the present invention having such a configuration, the bank number setting means selects, for each character or graphic of the print information, the largest bank number among those smaller than the drawing address.

The address of the frame memory corresponding to the selected bank number is controlled by the bank forming means as the head address.

Characters or graphics are drawn based on the controlled addresses.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a block diagram showing a circuit configuration of essential parts of a color printer to which the present invention is applied.

Reference numeral 1 is a CPU (centr
al processing unit).

A ROM (read only memory) 2 in which program data for processing performed by the CPU 1 is stored, the C
A RAM (random access memory) 3 in which areas of various memories used by the PU 1 for processing are formed, a serial interface 4 (or parallel interface) for controlling data transmission with a host computer through a line, and this serial A reception buffer 5 for temporarily storing data received by the interface 4, a frame buffer 6 for expanding print data, a frame buffer address setting circuit 7 as a bank forming means for setting a drawing start address on the frame buffer 6, I / O (input / output) for inputting / outputting signals to / from external peripheral devices
The command and data to be supplied to the port 8 and the engine unit 9 that performs the actual printing operation are set.
Each lport random access memory) 10 is connected to the CPU 1 via a first system bus 11.

Although not shown, the engine section 9 is a CP.
U, ROM, RAM, etc. control unit, a motor for conveying paper, yellow (Y), magenta (M), cyan (C
), Black (B) ink ribbons, and a plurality of print heads mounted on the frame buffer 6 and the D.P.
Each is connected to the RAM 10. Therefore, the frame buffer 6 is formed with four drawing areas corresponding to the respective print colors (Y, M, C, B).

The engine unit 9 includes the D / P / RAM.
Based on the information set in 10, the paper (label paper)
To convey each print color (Y,
The print data and graphic data drawn in the drawing areas corresponding to M, C, and B) are printed on the paper by each print head.

The first system bus 11 and the second system bus 12 are composed of various buses such as a data bus and an address bus.

The frame buffer 6 is a DRAM (dyn
amice random access memory) 21
As shown in FIG. 4, a 4-terminal input NAND circuit 22 and a latch circuit 23 are provided.

At each input terminal of the NAND circuit 22,
The address registers A16 to A19 of the CPU1 (Intel system 80186) are connected to each other, and
The output terminal of the circuit 21 is a negative logic CE of the DRAM 21.
It is connected to the terminal.

The address register A0 of the CPU 1 is connected to terminals A0 to A15 of the DRAM 21, respectively.
To A15 are connected, and A16 to A2 of this DRAM 21
0 to banks D0 to D4 via latch circuits, respectively.
Is connected.

Frame buffer address setting circuit 7
Are three registers 31, 32, 3 as shown in FIG.
3 and an adder circuit 34. In the first register 31, 0000 is fixedly set in the lower 4 digits, and the bank N is set in the upper 12 digits by the I / O port 8.
o. Is set. The second register 32 has the C
PU1 sets the offset address in the bank via the address bus. The adder circuit 34 adds the two registers 31 and 32 and sets the addition result in the third register 33. This third register 33
The data set to is output to the frame buffer 6 as an output address.

FIG. 4 is a diagram showing a schematic configuration (schematic software configuration) of a program for processing performed by the CPU 1.

A command such as a print format such as character type, print coordinates, print color, print data, graphic data, etc. sent from the host computer, and an issue command in which parameters such as print speed, print method, number of prints, etc. are set. It is transmitted via a line and received by the serial interface 4.

Serial interface driver 41
When the command is received by the serial interface 4, the command temporarily stores the received command in the reception buffer 5 and activates a PC (personal computer) application task 42.

The PC application task 42 reads the command temporarily stored in the reception buffer 5, edits and analyzes it, and draws commands and issues commands.
The drawing / printing management task 43 is activated, and drawing-related commands and issuing commands are passed to this drawing / printing management task 43.

That is, the PC application task 42 uses the command queue (command buffer) Y44, the command queue M45, and the command queue for the edited and analyzed commands (data) for each color (Y, M, C, B) of the ink ribbon. C46 and the command queue B47 are sequentially written, and the drawing / printing management task 43 receives the commands (data) from the command queues 44, 45, 46 and 47 in the order written by the PC application task 42. ) Is read.

For the drawing command, the drawing / print management task 43 switches the bank of the frame buffer 6 by a bank switching process 48, which will be described later, and calls the drawing utility 49 of the subroutine to set each print color (Y, Y,
For each M, C, B), a drawing process for drawing print data or graphic data in each drawing area of the frame buffer 6 is performed. Then, the sequence is repeated for each drawing command.

For the issue command, the D.
Each parameter of the issuing command is set in the P-RAM 10 and necessary information is written.

FIG. 5 is a diagram showing the flow of the bank switching process performed by the CPU 1 described above.

First, the drawing color (printing color) data is obtained from the received drawing command.

With respect to the obtained drawing color, the head address (F) of the corresponding drawing area of the frame buffer 6 is obtained.

Next, the drawing address (P) data of the character or graphic to be drawn is obtained from the drawing command.

Next, the start address (F) of the drawing area corresponding to the above-mentioned drawing color and the drawing address (P) of the character or graphic to be drawn are added (T = P + F),
The drawing address (T) on the frame buffer 6 is obtained.

Drawing address on this frame buffer 6
Divide (T) by 16 (B = T / 16), bank N
o. (B) is obtained (bank number selection means).

Drawing address on frame buffer 6 (T
) Is the bank number. Divide by the result of multiplying (B) by 16
(S = [remainder of T / (16 × B)]), and its remainder (the upper 12 digits of the address are all 0s, and the lower 4 digits are in effect), and the offset address in the bank Get as (S). That is, the obtained offset address (S) is set in the second register 32 of the frame buffer address setting circuit 7.

When the offset address (S) is set in the second register 32, the bank number. (B) is output to the I / O port 8 and the subroutine drawing utility 49
This is called so as to perform a character or graphic drawing process (drawing call), and the bank switching process is ended.

Frame buffer address setting circuit 7
Then, the bank No. set in every 16 bytes set in the first register 31. The start address of the bank (the address in which the lower 4 digits of all 0s are added to B) and the offset address set in the second register 32
(S) is added by the adder circuit 34, and the third register (output address
) 33 is set.

In drawing, the third register 33
Drawing is started from the drawing start address set in.

In this embodiment having such a structure, the bank is not fixedly formed in the frame buffer 6, but is flexibly formed based on a drawing command (including print data).

That is, the drawing address for drawing a character or graphic is obtained from the drawing command, and the bank No. corresponding to the nearest position before this drawing address in 16-byte units. (The value of the address in which the lower four digits 0000 of the address in 16-byte units are omitted) is specified. And this bank No. The offset address of the print start address of the character or graphic data in the bank specified by is calculated.

Obtained bank No. And the offset address are set in the frame buffer address setting circuit 7. Therefore, drawing on the frame buffer 6 is started by the drawing start address output from the frame buffer address setting circuit 7.

As a result, bank No. If the bank is switched by the bank No. The bank specified by is in the range of 64 kbytes from near the drawing address for drawing characters or graphics, and all graphic image data such as characters (character strings) or barcodes fit within the bank.

Therefore, the character or graphic is not drawn over two or more banks, and the bank switching process is eliminated (reduced) during drawing of the drawn character or graphic.

As described above, according to this embodiment, the bank No. corresponding to the nearest position before the drawing address for drawing a character or graphic in units of 16 bytes. Specify the bank number. The offset address of the drawing address in the bank specified by the By providing the frame buffer address setting circuit 7 in which the drawing start address is set from the offset address and the drawing start address and starting the drawing based on this drawing start address, the number of bank switching in the drawing can be reduced. The processing time can be shortened.

[0061]

As described above in detail, according to the present invention,
By forming the bank in the frame memory based on the drawing address of the character or graphic, it is possible to reduce the number of times of bank switching in drawing, and thus to provide a printer that can shorten the drawing processing time.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of a main part of a color printer according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a frame buffer of the color printer of the embodiment.

FIG. 3 is a block diagram showing a circuit configuration of a frame buffer address setting circuit of the color printer of the embodiment.

FIG. 4 is a block diagram showing a schematic software configuration of the color printer of the embodiment.

FIG. 5 is a diagram showing a flow of bank switching processing performed by the color printer of the embodiment.

FIG. 6 is a diagram showing a configuration of an entire memory map of a conventional color printer.

FIG. 7 is a diagram showing an example of printing a label.

[Explanation of symbols]

 1 ... CPU, 6 ... Frame buffer, 7 ... Frame buffer address setting circuit, 8 ... I / O port.

Claims (1)

[Claims] 1. A frame memory is provided which can form a plurality of banks each having a preset number of bytes, print information is drawn for each bank formed in the frame memory, and the drawn data is called to print on a sheet. In a printer for printing, a bank number is set in a predetermined byte unit at the address of the frame memory, and a maximum bank number smaller than the drawing address is selected for each character or graphic of print information. Means and bank forming means for controlling the address of the bank with the address of the frame memory corresponding to the bank number selected by the bank number selecting means as the start address.
A printer which performs drawing based on an address controlled by the bank forming means.