JPS5918736B2 - Code conversion method - Google Patents

Description

[Detailed description of the invention] This invention relates to a code conversion method.

General external code systems include JIS 7 units and affiliated printing and telegraph 6 units, but the number of shift stages and the number of bits constituting one code differ. For this purpose, a code conversion procedure must be followed according to the external code system. Therefore, when converting codes, it is necessary to follow a code conversion procedure according to the external code system, so it is necessary to prepare separate software or hardware.

An object of the present invention is to eliminate the above-mentioned conventional problems, and to provide a code conversion method that has the effect of being able to perform code conversion using a fixed procedure regardless of the number of shift steps and units of an external code system. It's about doing.

The feature of this invention is that a code conversion table is provided with a shift code section, a code unit information section, and an internal code section, and whether or not an input code is a shift code is determined by referring to the shift code section. , if the code is a shift code, a shift mode management unit provided outside the code conversion table stores information corresponding to the shift code, and if the code is not a shift code, the shift mode management unit stores information corresponding to the shift code; The purpose is to obtain a converted code by uniquely determining the address of the internal code section through calculations that treat the contents of the code unit information section and the corresponding manual code as binary numbers.

Next, embodiments of the present invention will be described in detail using the drawings.

FIG. 1 shows the structure of a code conversion table according to an embodiment of the present invention.

The code conversion table 1 includes a shift code section 2, a code unit information section 3, and an internal code section 4, and a shift mode management section T is provided outside the code conversion table 1.

Each piece of information has a minimum unit of 8 bits.
All shift codes are written in the shift code section 2, and up to eight types of shift codes can be set and defined as shift codes (n) from shift code (0) to shift code (7) in order.

In the JIS 7 unit, a code including a parity bit is entered, and in the 2nd type printed telegraph 6 unit, 3 types of shift codes are entered. Also, extra parts are filled in with hexadecimal numbers (00). In the code unit information section 3, information on the number of bits constituting one code is expressed in a bit pattern.

In the JIS 7 unit, there are 8 bits including the parity bit, so a binary number (11111111) is entered, and in the subscriber print telegraph 6 unit, it is 6 bits, so a binary number (0011) is entered.
1111) is entered. The internal code after conversion is written in the internal code section 4, and its contents correspond to the shift mode (n), such as table 5 for shift mode (0) and table 6 for shift mode (1). Areas are divided by Here, the shift mode (n) is defined as the shift mode after inputting the shift code (n). In the shift mode (n) area of the internal code section 4, the internal code corresponding to the input code hexadecimal (00),
The internal codes are written in order, such as the internal code corresponding to the input code hexadecimal (01). However, 16 in the shift code part
The shift mode (n) area written with the base number (00) is unnecessary and does not exist. Also, as a general rule, the internal code is 8
Since it is a bit, the number of codes that can be defined will not exceed 256 types, and if parity bits are excluded, the number of external codes that can be defined in shift mode will not exceed 256 types. Therefore, the input code including the parity bit is 51.
The capacity of internal cord section 4 is 51.
It is 2 bytes (1 byte is 8 bits). The internal code corresponding to the input parity error data is 16.
The internal code corresponding to human-powered data that is entered as a base number (00) to be distinguished and ignored without being treated as data is 1.
Enter hexadecimal number (FF) and judge. The shift mode management section 7 is not included in the code conversion table 4 and is prepared as one of the information when referring to the table, and stores the shift mode when inputting an external code.

Shift mode management is 1 corresponding to shift mode (0).
This is done by writing the numerical value n of the shift mode (n) as a hexadecimal number (01) corresponding to a hexadecimal number (00) shift mode (1). The input code is first hexadecimal (0
0).

This is because hexadecimal (00) is used as the margin data of shift code section 2, and in reality hexadecimal (00) is used as the margin data of shift code section 2.
0) is not used as a shift code, and there is no need to determine whether or not it is a shift code. The input code is hexadecimal (
00), it is determined that it is not a shift code.

In other cases, it is compared with all data in the shift code section, and if there is a match, the corresponding manual code is determined to be a shift code, and the value of n of the matched shift code (n) is entered in the shift mode management section 7. do. By this operation, the corresponding shift mode is entered when a shift code is input, and is stored and retained until the next shift code is input. If it is determined that the input code is not a shift code, the internal code section 4 is referenced to obtain the internal code.

The table reference address at this time is determined as follows. Since the data in the code unit information section 3 indicates the maximum number expressed by the external code, adding 1 to this indicates the type of bit combination of the external code, that is, the capacity occupied by the shift mode (n) in the internal code section 4. This will show the following.

For this reason, if the data in the code unit information section 3 plus 1 is multiplied by n, the input code (0
The address of the internal code information corresponding to 0) is obtained as the address in the internal code section 4, and by adding the input code to this value, the 1-byte address in which the target internal code is written is obtained.

For example, in the case of JIS 7 units, all 8 bits of the data in the code unit information section 3 are logical '1', or decimal number 255, as described above, so the value obtained by adding '1' to this, or decimal number 256, is the internal It refers to the capacity corresponding to the 1 shift mode in the code section 4.If shift mode (1) is defined as SO, when the SO code is input, the contents of the shift mode management section 7 become "1". In this state, for example, if the external code hexadecimal (B1) is input, the value 289 obtained by adding the decimal number 33 to 256 becomes the address in the internal code section 4, and by referring to this, the internal code can be obtained. can. The above procedure can be realized by either software control or hardware control. Furthermore, if the input code is within 8 bits and the number of shift stages is within 8 stages, this procedure is constant regardless of the external code system, and replacing the code conversion table does not affect other controls at all.
Although the shift code section 2 is capable of shifting up to eight stages, it may be three stages if two types, JIS 7 unit and subscriber printed telegraph 6 unit, are targeted.

Conversely, it is also possible to set more than eight stages. The arrangement of the shift code section 2, code unit information section 3, and internal code section 4 does not affect the effects of the present invention.
They can also be defined interchangeably.

The shift mode storage in the shift mode management section 7 is as follows:
It can also be the start address of each shift mode area in the internal code section 4.

In this case, the procedure of adding 1 to the contents of the code unit information section 3 and multiplying it by the mode number n is performed when inputting the shift code. As described above, according to the present invention, the code conversion table has the shift code and code unit information, and the table reference address is obtained by calculating the shift mode number, code unit information, and input code in a fixed format. You can handle different external code systems without changing the software or hardware by simply replacing the .

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a code conversion table showing an embodiment of the present invention. 1... Code conversion table, 2... Shift code section, 3... Code unit information section, 4...
...Internal code section, 5...Shift mode (0) table, 6...Shift mode (1)
Table 7...Shift mode management section.

Claims (1)

[Claims] 1 A method of converting a preset external code into an internal code using a code conversion table, which includes a code conversion table including a shift code section, a code unit information section, and an internal code section, and a shift table that stores a shift mode. The shift mode management section stores information corresponding to the position of the corresponding shift code in the shift code section, and the code unit information section stores information corresponding to the position of the corresponding shift code in the internal code section. Information indicating the corresponding capacity is stored, and by referring to the shift code section, it is determined whether or not the input code of the arbitrary number of stages is a shift code. If it is determined that it is not a shift code, the code unit is The size of the area corresponding to each shift mode in the internal code section is determined by referring to the information section, and the address of the internal code is determined by referring to the shift mode section management section. A code conversion method characterized by obtaining an internal code from a part.