JPS6027936A - Control system of printer - Google Patents

Abstract

PURPOSE:To connect a printer to various external devices by providing a tape for function code storage in the printer, and transferring and storing function codes for the external devices. CONSTITUTION:When a telegraphic message (a) is transferred from an external device through an I/O port 10, a CPU7 inputs data (b) and decodes the telegraphic message by a program stored previously in an ROM8. In this method, the address 000 of an RAM9 is specified by a telegraphic message (OO)H to store the code 1C of a telegraphic message FS, and this external device is specified to a 10cpi (character per inch) pitch. When this is indicated to the printer with another function character RS, the code 1E of a function character RS is only stored in the address 0000. Namely, a function code is specified optionally from the external device.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a printer control method for changing or deleting printer function codes according to instructions from an external device.

(Prior art) Printers generally print characters and characters according to the character code table shown in Figure 1.
Symbols, etc. are printed. In this character code table, 1 b8. b7. b6. b5 is the upper 4 bits of the character code,
2 b4. b3゜b2. bl represents the lower 4 bits of the character code. 3 is the MSB (
(most significant bit) and b5 is LSB (least significant bit)
It is expressed in hexadecimal, and 4 is the lower 4 above.
Bit b4 is MSB, b1 is I, SB is 1
It is expressed in hexadecimal. 5 is an area for characters, symbols, etc., and 6 is an area for functional characters. To specify the character It A IT in a character code table with this structure, use the code ``41'''' and the function character ``FS''.
To specify, give the code "ic".

In recent years, there has been a demand for personal computers to be used as external devices, that is, to have versatility. However, since the usage of the functions in the function character alias in the character code table differs from computer to computer, some countermeasures have been taken in the past. As a conventional measure, the function code conversion table (for example, ROM
) is provided in the printer, and the operator selects this conversion table using means such as a switch. However, as the types of computer computers increase and the number of conversion tables described above increases, the method described above has the disadvantage that it becomes difficult for printers to have the functionality to be compatible with all the computer systems. Another measure is to change the 7° program for determining the printer's function depending on the connected personal computer, but this is difficult and impractical.

(Objective of the Invention) The present invention has been made in view of the above points, and aims to provide an improved printer control system that connects a printer to an external device in each building with a simple operation. The goal is to provide the following.

(Structure of the Invention) In order to achieve the above object, the present invention provides a table for storing function codes inside the printer, and a function code corresponding to the function determined in an external device is assigned to an address assigned in advance for each function in the table. A code is transferred and stored in advance from an external device, and thereafter the table is searched using the function code transferred from the external device to find out the function corresponding to the code, which will be described in detail below.

(Example) FIG. 2 shows a configuration diagram of a printer control circuit according to the present invention, and 7 is a microcontroller (CP) that controls the printer.
U), 8 is a read-only memory (ROM) that stores 70 programs, 9 is a read-write memory (RAM) that stores print data, tables, flags, etc., 7
o is an input/output port (I10 port) to which an interface section (not shown), a space, a line feed motor, and a driver section for driving the print head are connected, 171dr-tapas, 12
is the address bus. In the printer control circuit configured in this way, the RAM 9 is stored in advance for each function as shown in Fig. 3 (c).
) Assume that addresses are assigned as shown in FIG. Here - as an example, the function of 10 characters/inch is the address "0000", and the function of 12 characters/inch is the address "0000".
0001°', 17 characters/inch function is address "00"
02". However, the address is not limited to the above example, and it goes without saying that the correspondence between functions and addresses is not limited to this. When the message shown in FIG. 3(a) is transferred to the CPU 7 via the I10 port 10 (the data shown in FIG. 3(b) is input to the CPU 7), the CPU 7 transfers the data stored in the ROM 8 in advance. Decipher the above message using the program.Now, instruct the ESCA of the message to store the function code in the function table.Continue <(00)
+1. (Ol))I.

(02) Define H as the storage address of the function table, * as the separator, continuation (FS, GS, R8 as the function character for specifying character pitch, and continuation: as the end code). Here, (00)H etc., H means a hexadecimal number. When the CPU 7 detects ESCA in the message, it performs a function operation on the function table. This operation is
The message (00)H following SCA indicates the address of RAM9.
o o o o” and the message FS code following the separator * °' l C” (00011100)
is to store. Therefore, this external device has 10 characters/
Indicates that the character pitch in inches is specified by the function character 'FS'.When an external device instructs the printer to specify the character pitch in 10 characters/inch by another function character 'R8', the address °' o o o o “The code for the functional character R3 is “I E” (000111
10) should be stored. The same applies to 12 characters/inch and 17 characters/inch.

Next, when using this function table, when the function code 'LD'' (function character GS) is transferred from the external device to the CPU 7, the CPU 7 refers to the data of the function table in the RAM 9 and sets the data +11p. +
Find the function table address where the same data as + is stored. If a function code is stored in the function table according to an instruction from an external device as shown in Figure 3 (C), then C
PU 7 has the same data at address ""OOOl""
Knowing that ``D'' is stored, the printer performs the following operations at a character pitch of 12 characters/inch, which is fixed at this address. Once the function table is set up, the function code can be inputted into the printer according to the format from an external device before the actual printing process is performed.

As explained above, since a function code can be specified arbitrarily from an external device, there is an advantage that the printer can be connected to various external devices.

In the first embodiment, all the function codes are input from the external device, but a method in which the pre-programmed function codes are stored in the ROM and transferred to the function table in the RAM when the printer is turned on, and only the function code to be changed is input from the external device. Also good. In addition, by using non-volatile RAM (NOVRAM) and electrically erasable ROM (EEFROM'), the function code once set is retained and the function code is saved every time the power is disconnected. It is also possible to use a method that eliminates the need to re-enter the Shinneng code.

Further, in the first embodiment, a single function code is explained, but it goes without saying that the invention can be extended to function codes composed of two or more bytes.

FIG. 4 shows an example of a function code composed of 2 bytes as a second embodiment. The second example is an example of a function code that specifies the line feed pitch. 6 lines/inch is specified by ESC6,
This is a case where 8 lines/inch is specified as ESC8.

In the message of FIG. 4(a), ESCB is an instruction to store a function code consisting of 2 bytes in a function table,
Continuation < (1o)H, (12)H is the storage start address of the function table, the following tree is the separator, continuation (ESC6, E
SC8 is a function character that specifies a 2-byte function code, and the following: is an end code. Function code is 2
In the case of byte configuration, the operation is similar to that of the first embodiment except that the function code is stored in 2 bytes of consecutive addresses of the function table in RAM, but it has more functions than the first measurement example. It has the advantage of being configurable.

Next, if you want to delete the contents of the function table, see Figure 5 (
, ) is transferred from an external device to the printer. In the message of FIG. 5(a), ESCA is a write command to the function table as described above, the following (XX)H is the write address of the function table, the following tree is a separator, and the following < NUL
This is a function character indicating that the function is disabled (that is, this function is not used in this device), and its code is 00''.

Continuing: This is the end code. As shown in Figure 3, by writing the code "o o" corresponding to the function character NUL in a function table address that is not used by this device, the printer will find the "o o" code in the function table and write the corresponding function to this device. I know it's unused. By defining unused function codes in the function table in this way, it is possible to easily distinguish between used functions and unused functions. However, the above deletion command is not limited to the message shown in FIG. For example, the deletion command in this case is to use ESCC at the beginning of the message.
C(xx)H: may be used. In the above explanation, better effects can be obtained by first clearing the function table inside the printer (for example, storing the code "°00" in all addresses of the function table) and then setting only the necessary functions. Needless to say, it can be done.

Further, although the unused function code in the function table is set as Pa00'', other codes may be used.

(Effects of the Invention) As described in detail above, according to the present invention, the printer is provided with a function table that can store function codes for the functions of the printer, and the contents of the function table can be read by designation from an external device. By rewriting one printer program, there is an advantage that it can be connected to various external devices with different function codes.

[Brief explanation of the drawing]

Figure 1 is a diagram showing a character code table, Figure 2 is a configuration diagram of the printer control circuit, Figure 3 (,) is a diagram showing a message transferred from an external device, and Figure 3 (b) is a diagram showing a message transferred from an external device. 1 message of (a)
FIG. 3(c) is a diagram showing the function table, FIG. 4(,) is a diagram showing the message according to the second embodiment, and FIG. ) is a hexadecimal representation of the message, FIG. 4(c) is a diagram explaining the function table according to the second embodiment, and FIG. 5(a) is a diagram showing the message for deleting the contents of the function table. , Figure 5(b) is Figure 5(b)
A diagram showing the message in a) in hexadecimal notation, and FIG. 5(c) are diagrams for explaining deletion of the function table. 7... CPU, 8... ROJ 9...
- R No. Jν1, no 0...I10 port, l...data bus, 12...address bus. Patent amount □ Applicant Oki Electric Industry Co., Ltd. Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] In a printer control system that executes a function using a function code transferred from an external device, a function table for storing the above function code is provided inside the printer, and an address assigned to each function in advance in the printer is stored. The function code for the determined function and a specific code indicating an unused function are transferred and stored in advance from the external device to the external device, and thereafter the function code transferred from the external device is checked in the above function table and the function code is checked. A printer control method characterized by knowing functions for codes.