JPH0477787A - Character pattern readout device - Google Patents

Abstract

PURPOSE:To obtain a corresponding ROM address without using a code/ROM address conversion table by providing a system recognizing means which recognizes a system to which an inputted character code belongs and outputs the character code to an encoder circuit in the system to which the character code belongs. CONSTITUTION:When a KANJI(Chinese character) code in a specified KANJI code system is inputted in a CPU 10, the KANJI code is outputted to a CPU address line 11 as it is and the KANJI code system is judged so as to select the encoder circuit 12 set in the KANJI code system. The CPU 10 decides the combination of data given to the input terminals and B of a decoder 16 in accordance with the selected encoder circuit 12 and the combination of the data is outputted to a CPU data line 15. The corresponding ROM address is obtained without using the code/ROM address conversion table in such a way, and the time required for outputting the character is shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] [Field of Industrial Application] The present invention relates to a character pattern reading device that is compatible with a plurality of different character code systems.

[Conventional technology]

Conventionally, a character pattern is stored in advance at each address in ROM, and the character code entered manually is converted to the ROM address where the corresponding character pattern is stored to read out the desired character pattern. A readout device is being considered.

This character pattern reading device is applied to character output devices such as CRT displays and printers, and forms predetermined characters from read character patterns. In the following, a kanji code will be used as an example of a character code.

Kanji codes include JIS, Kuten, and Shift JIS.

There are several different systems such as EUC. Conventionally, in order to support a plurality of different kanji codes, a character pattern reading device was configured as shown in FIG. 3, and a kanji code/ROM address conversion table was stored in the table memory 1 for each kanji code system. I had it memorized. And the CPU
When a kanji code of any system is input to 2, the code/ROM address conversion table of the code system to which the kanji code belongs is read out from the table memory 1, and the corresponding kanji pattern is stored by referring to this table. Find the ROM address. The obtained ROM address is outputted to an address line 4 connected to the kanji ROM 3, and the kanji pattern stored at that address is outputted to a data line 5.

However, each time a kanji code is input to the CPU 2 in response to a kanji output request, the code/ROM address conversion table is read to obtain the ROM address, which takes a long time to process and output kanji characters.

[Problem to be solved by the invention] As described above, the conventional character pattern reading device takes time to find the ROM address where the character pattern corresponding to the kanji code is stored, and the responsiveness until it outputs the kanji character is poor. There was a problem with it being bad.

The present invention has been made in view of the above-mentioned circumstances, and it provides a character pattern that allows the corresponding ROM address to be found without using a code/ROM address conversion table, thereby reducing the time required to output characters. The purpose is to provide a reading device.

[Structure of the Invention] [Means for Solving the Problems] In order to achieve the above object, the present invention has a ROM in which character patterns are stored at each address, and when a character code of any system is input, , a character pattern reading device that converts the character pattern corresponding to the corresponding character code into an address where it is stored and reads out the character pattern at this address, is provided for each character code system used, and each given A plurality of encoder circuits convert each character code into an address of the ROM in which a character pattern corresponding to the character code is stored, and a system that recognizes the system to which the input character code belongs and converts the character code to the character pattern corresponding to the character code. and a system recognition means for outputting the code to the encoder circuit of the system to which the code belongs.

[Effect]

In the present invention, by taking the above measures, the system of the input character code is recognized by the system recognition means, and is output to the encoder circuit of the code system.

The character code is converted by an encoder circuit into an address where a character pattern corresponding to the character code is stored.

A desired character pattern is then read from this address.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 is a diagram showing the configuration of a character pattern reading device according to an embodiment. In this character pattern reading device, a plurality of encoder circuits 12a to 12d are connected in parallel to a CPU I O through which a kanji code is input via a CPU address line 11, and each encoder circuit 12a to 12d is connected to a ROM address line 13. It is connected to the ROM 14 via the ROM 14.

Further, a decoder 16 is connected to the CPU I O via a CPU data line 15, and a plurality of output terminals of the decoder 16 are connected to each of the encoder circuits 12a to 12d, respectively.

The number of encoder circuits 12 corresponding to the number of kanji code systems used is installed. The figure shows four cases. Each encoder circuit 11a to 11d includes a CP
A Kanji code is given via the CPU address line 12 from Ul0. Each of the encoder circuits 12a to 12d is set to a different kanji code system, and converts the kanji code given from the CPU address line 11 into a ROM address in which the corresponding kanji pattern is stored according to the respective kanji code system. The circuit is configured as follows. The outputs of these encoder circuits 12a to 12d are three-state, and all circuits except one circuit are set to high impedance by an operation signal from the decoder 16.

The decoder 16 has two input terminals A and B to which signals from the CPU data line 15 are applied, and four output terminals to output operation signals to the corresponding encoder circuits 12a to 12d. It is constructed of logic circuits as shown in the truth table below.

Furthermore, the decoder 16 is connected to an I10 control line 17 whose one end is connected to the CPU10, and this I10 control line 17 is connected to the CPU10.
No. 13 of the CPU data line 15 is taken in by a timing signal applied via the control line 17.

When the kanji food is input, the CPU10 determines the kanji code system, determines the combination of data to be applied to the input terminals A and B of the decoder 16, and outputs the determined combination data to the CPU data line 15. and a function of outputting a timing signal for the decoder 16 to take in data from the CPU data line 15 when the Kanji code system changes.

Next, the operation of the character pattern reading device configured in this manner will be explained. When a kanji code of a predetermined kanji code system is input to the CPU10, the kanji code is output as is to the CPU address line 11, and the kanji code system is determined and the encoder circuit 12 set to the kanji code system is activated. select. The CPU 10 determines the combination of data to be applied to the input terminals A and B of the decoder 6 according to the selected encoder circuit 12, and outputs the combination of data to the CPU data line 15. For example, if the encoder circuit 12a is set to the Kanji code system of the input Kanji code, the data line 15 is given a signal of a combination of "0" for the A terminal input and "1" for the B terminal input. And I10 control line 1
7, data line 1
5 is taken in, and as a result, the encoder circuit 1 is set to the input kanji code system from the decoder 16.
A low active signal is applied only to encoder circuit 2, and the other encoder circuits 12 become high impedance. Therefore, only the output of the encoder circuit 12 set to the input kanji code system becomes active, and this encoder circuit 12
The ROM address converted in is output to the ROM address line 13. Then, a desired kanji pattern is read from the ROM address output to the ROM address line 13.

In this way, according to this embodiment, the encoder circuit 12 is installed for each kanji code system to be used, a kanji code is given to each encoder circuit 12, and only the encoder circuit 12 set to the input kanji code system is used. Activate it and
Since I made the other circuits high impedance,
By outputting the kanji code input to the CPU 10 as it is to the address line 15, the ROM address in which the desired kanji pattern is stored can be obtained. Therefore, there is no need to read the code/address conversion table each time, and the time required to output Chinese characters can be significantly reduced. Further, since a table memory for storing a plurality of code/address conversion tables is not required, memory capacity can be reduced.

Note that the above embodiment includes a plurality of encoder circuits 12a to 12.
An example has been shown in which the CPU data line 15 and the decoder 16 are used to select the encoder circuit 12 of the kanji code system to be used from among the encoder circuits 12 of the kanji code system to be used. The circuit 12 may be selected by the user using the switch 21. By adopting such a configuration, the circuit configuration can be further simplified.

[Effects of the Invention] As detailed above, according to the present invention, the corresponding ROM can be read without using a code/ROM address conversion table.
It is possible to provide a character pattern reading device that can obtain addresses and shorten the time required to output characters.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a character pattern reading device according to an embodiment of the present invention, FIG. 2 is a diagram showing a modification of the same embodiment, and FIG. 3 is a diagram showing a modification of the same embodiment.
The figure is a configuration diagram of a conventional character pattern reading device. 10...CPU, 11...cpu address line, 12
...Encoder, /IiD path, 13...ROM address line, 14...ROM, 15...CPU data line,
16...Decoder, 17...I10 control line. Applicant's agent Patent attorney Takehiko Suzue Figure 2

Claims (1)

[Claims] A ROM having a character pattern stored at each address,
When a character code of any encoding system is input, the character pattern reading device converts it into an address where the character pattern corresponding to the character code is stored and reads out the character pattern at this address.Character used by the character pattern reading device. a plurality of encoder circuits each set in a code system of the code and converting each given character code into an address of the ROM in which a character pattern corresponding to the input character code is stored according to each code system; A character system comprising system recognition means for recognizing a code system to which an input character code belongs and outputting the character code to a predetermined encoder circuit set to the code system to which the character code belongs. Pattern reading device.