JPH03260841A - Code converter - Google Patents

Abstract

PURPOSE:To improve the reliability of data by providing an LRC production circuit which adds the LRC data to the input data, an inverse conversion circuit which converts inversely the data converted by a data conversion circuit together with the LRC data, and an LRC checking circuit which applies the LRC check to the inversely converted data. CONSTITUTION:This converter is provided with an LRC production circuit 2 to add the LRC data to the input data, the inverse conversion circuit 3 which converts inversely the data converted by a data conversion circuit together with the LRC data, and an LRC checking circuit 4 which applies the LRC check to the inversely converted data. The circuit 2 adds the LRC data to the input data to be given to a code conversion circuit 1. The circuit 3 converts inversely the data converted by the data conversion circuit together with the LRC data and turns these data into the original codes. Then the circuit 4 performs the LRC check of the data converted inversely. Thus it is possible to check errors at the conversion of data and to improve the reliability of data.

Description

Detailed Description of the Invention (Summary) It relates to a code conversion device, and particularly to a code conversion device having a code conversion circuit that converts input data expressed in a specific code into another code. In a code converter equipped with a code conversion circuit that converts input data expressed in a specific code into another code, LRC data is added to the input data in order to perform checks and improve data reliability. An inverse conversion circuit that inversely converts the data converted by the data conversion circuit together with the LRC data, and an LRC check circuit that performs an LRC check on the inversely converted data are provided.

(Industrial Application Field) The present invention relates to a code conversion device, and more particularly to a code conversion device equipped with a code conversion circuit that converts input data expressed in a specific code into another code.

(Prior Art) Generally, data expressed in a specific code may be converted into another code. This converts, for example, data written in ASCII format to EBCDIC (Extended Binary Coded Decimal Code) format, and vice versa. Conventionally, there is a code conversion device shown in FIG. 3 as such a code conversion device. A PROM 31 is provided as a code conversion circuit, and a code conversion table is stored in this PROM.Input data is expressed by a specific code and is expressed by another code corresponding to input data to which parity pits are added. It also generates additional output data. This code conversion circuit also performs a parity check on input data.

[Problem to be solved by the invention]

By the way, in the above-mentioned conventional code conversion device, the reliability of the input data and output data itself is guaranteed by adding parity pits, but there is no verification as to whether the conversion itself is performed accurately. There wasn't. Therefore, PRO, which is a data conversion circuit,
It is not possible to check for conversion errors caused by abnormalities in segments of M.

Therefore, the present invention can perform error checking during data conversion,
The purpose of the present invention is to provide a code conversion device with improved data reliability.

(Means for solving the problems) In the present invention, the means for solving the above problems are as follows:
As shown in FIG. 1, in a code conversion device comprising a code conversion circuit 1 that converts input data expressed in a specific code into another code, an LRC creation 2 that adds LRC data to input data is used. In addition, an inverse conversion circuit 3 that inversely converts the data converted by the data conversion circuit together with the LRC data, and an LRC check circuit 4 that performs an LRC check on the inversely converted data are provided.

[Effect]

According to the present invention, LRC data is created by adding LRC data to the input data to the code conversion circuit, and the inverse conversion circuit adds the LRC data to the input data to the code conversion circuit.
The data converted by the data conversion circuit together with the C data is inversely converted back to the original code. Since the LRC check circuit performs an LRC check on the inversely converted data, it is possible to detect conversion errors in the code conversion circuit.

(Example) An example of a code conversion device according to the present invention will be described below based on the drawings.

FIG. 2 shows an embodiment of the code conversion device according to the present invention. In this embodiment, the code conversion device is ASC
From II format to EBCDIC format and vice versa
It is capable of converting from IC format to ASCII format.

In the same figure, 11 is a programmable logic generator (PLD) that creates LRC data that adds LRC data used for horizontal redundancy check to input data.
Device), 12.13 is a register (Reg) for tying adjustment, and 14 is a selector switch for input selection (
SW), 15 is a PROM which is a code conversion circuit from ASCII format to EBCDIC format, and 16 is an EBC
PROM, IT, 18, which performs code conversion from DIC format to ASCII format, is a register for tying adjustment (
Reg), 19 is a multiplexer for input switching (MPX
), 20 indicates a PAL as an LRC check means for performing an LRC check. Here, the above two FRs
The OMs have a mutually inverse transformation relationship.

Next, the operation of the embodiment of the code conversion device according to this embodiment will be explained. First, ASCII format data EBCDIC
The case of converting to format data will be explained.

The input ASCII data is
RC data is added and the selector switch 14 selects PROM1.
5 and is converted into EBCDIC data including LRC data. And the output is forked, while (
(2) is inputted into the register 18, inputted into the PROM 16, and converted into ASCII data again. Its output (■) passes through multiplexer 19 to PAL2 for LRC check.
0 and the horizontal redundancy is checked to see if the conversion was successful. The normality of the conversion can be guaranteed by this test result.

Next, a case will be described in which EBCDIC format data is converted to ASCII format data.

LRC data is added to the input EBCDIC data in the PLDII, and the PROM data is added to the input EBCDIC data by the changeover switch 14.
16, including LR and C data in ASCII
converted to data. The output is then branched, and one of the outputs (■) is input to the register 17 and then to the PROM 15, where it is again converted into EBCDIC data. Its output (■
) is the PA for LRC check via multiplexer 19.
The signal is input to L20 and the horizontal redundancy is checked to see if the conversion was performed normally. The normality of the conversion can be guaranteed by this inspection result.

Therefore, according to this embodiment, the input data is added to the LR
The code is converted together with the C data, and the data after this conversion is inversely converted again and subjected to an LRC check, so it can be confirmed whether the code conversion has been performed normally, thereby increasing the reliability of the code conversion process. I can do it.

In the above embodiment, ASCII and EBCDIC codes were used as examples, but it goes without saying that other codes may also be used. Further, in the above embodiment, a device capable of mutual conversion between two types of codes has been described, but it goes without saying that the present invention can also be applied to a device that only converts one code to another code in one direction.

(Effects of the Invention) As explained above, according to the present invention, the code conversion device creates an LRC command by adding LRC data to input data, and inversely converts the data converted by the data conversion circuit together with the LRC data. Since an inverse conversion circuit and an LRC check circuit for performing an LRC check on the inversely converted data are provided, conversion errors in the code conversion circuit can be detected and the reliability of the code conversion process can be increased. be effective.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the principle of the present invention, FIG. 2 is a block diagram showing an embodiment of a code converting device according to the present invention, and FIG. 3 is a block diagram showing a conventional code converting device. 1...Code conversion circuit 2...LRC creation circuit 3...Inverse conversion circuit 4...LRC check circuit Traveling whistle of the present invention 1 Figure

Claims (1)

[Claims] A code conversion device comprising a code conversion circuit (1) for converting input data expressed in a specific code into another code, comprising: an LRC creation circuit (1) for adding LRC data to input data;
2), an inverse conversion circuit (3) that inversely converts the data converted by the data conversion circuit together with the LRC data, and an LRC check circuit (4) that performs an LRC check on the inversely converted data.
) is provided.