JPS621043A - Checking system for program of microcomputer system - Google Patents

Abstract

PURPOSE:To improve the correspondence properties of the check to the change of a program by providing a check sum data display device and a check sum data setter at the outside of a ROM. CONSTITUTION:A microcomputer 30 issues the sum check sequentially to the program data written to a ROM 31 from the head address through the final address. The results of these sum checks are displayed on a check sum data display device 40 via a control bus 42 and a data bus 43. Then these displayed data are set to a check sum data setter 41 for storage of the check sum data. In such a way, the check sum data can be calculated automatically and also set.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a program checking method in a microcomputer system.

[Prior art]

FIG. 2 is a diagram showing an example of the configuration of a conventional microcomputer system. The microcomputer system includes a microcomputer 1, ROM (read only memory) 2, RAM (random access memory) 3. l1
0 (input/output) terminal 4 and an address bus connecting these terminals 5. It is composed of a data bus 6.

In the above-mentioned microcomputer system, in order to improve the reliability of the system, the ROM2 is
and checking the operation of RAM3. Of these, RO
The method of checking M2 is to perform a sum check of the data written in the program data area 10 of the ROM 2 by the microcomputer 1 as shown in FIG. By comparing with the sum data, the ROM
I was checking 2 for program corruption.

[Problem that the invention seeks to solve]

However, in the program check method of the conventional microcomputer system described above, since checksum data is written in ROM2 in advance, it is necessary to recalculate and rewrite the sum check data value every time the program data is changed. It was difficult to change the check data in response to changes. Furthermore, especially when changes to a program are made on a business trip, it is difficult to create check data for the program.

The present invention has been made in view of the above points, and an object of the present invention is to provide a program check method for a microcomputer system that can easily deal with program changes.

[Steps to solve problems]

In order to solve the above problems, the present invention provides sum check data that displays a calculated check sum data value of program data outside the ROM in a micro computer system equipped with a micro computer, a ROM, a RAM, and an I10 terminal. A program check method for a microcomputer system was constructed by providing a display and a checksum data setter for setting the checksum data.

[Effect]

As described above, by providing a checksum data display and a checksum data setting device outside the ROM, a microcomputer can automatically calculate the checksum data value and display it on the checksum data display. is possible, and the checksum data setter can be stored in ROM.
Since it is provided separately from the program, it is easy to set the checksum data when changing the program.Furthermore, even if the program is changed while on a business trip, the checksum data can be corrected on the business trip, making it possible to check for program changes. compatibility will improve.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a block diagram showing the configuration of a microcomputer system to which a program check method according to the present invention is applied. As shown in the figure, the microcomputer system includes a microcomputer 30. A ROM 31 into which program data is written, a checksum data generator 32 which generates checksum data for checking the program data written in the ROM 31. A RAM 33 into which various data are read and written, an address bus 35 that connects these devices to the I10 terminal 34 and the microcomputer 30. It is composed of a data bus 36.

FIG. 4 is a functional block diagram of the checksum data generator 32 of the microcomputer system shown in FIG. In the figure, 40 is a checksum data display for displaying checksum data, 41 is a checksum data setting device for setting checksum data, and 42 is a connection between the checksum data display 40 and the checksum data setting device 41. A control bus 43 is a data bus for transferring data.

In the microcomputer system having the above configuration, the microcomputer 30 sequentially sum-checks the program data written in the ROM 31 from the first address to the last address, and sends the M result to the control bus 42.
and the data bus 43 to display the checksum data on the checksum data display 40. Also, by setting the displayed data in the checksum data setting device 41, the checksum data is stored. In this way, automatic calculation of checksum data and setting of checksum data is possible.

〔Effect of the invention〕

As explained above, according to the present invention, since the checksum data display device and the checksum data setting device are provided outside the ROM, the following effects can be obtained.

(1) By providing the checksum data display, it becomes possible to automatically calculate and display the checksum data value using a microcomputer.

(2) By providing the checksum data setting device separately from the ROM, setting the checksum data by changing the program becomes easy.

(3) Even when a program is changed while on a business trip, the checksum data can be modified at the business trip, which improves adaptability to changes.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a microcomputer system to which the program check method of the microcomputer system according to the present invention is applied, and FIG. 2 is a block diagram showing the configuration of a conventional microcomputer system.
FIG. 3 is a diagram showing the memory format of the ROM, and FIG. 4 is a functional block diagram of the checksum data generator 32 of FIG. 1. In the figure, 30... microcomputer, 31...
・ROM, 32...Checksum data generator, 3
3...RAM, 34...I10 terminal, 35...
...Address bus, 36...Data bus, 40...
...Checksum data display, 41...Checksum data setting device, 42...Control bus, 4
3...Data bus. Stopped in September, Kohui 70 Combi] - Taziztem No. I
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Claims (1)

[Claims] In a microcomputer system, a display device external to a read-only memory provided in the microcomputer system displays checksum data for inspecting data stored in the read-only memory, and a checksum for setting the checksum data. 1. A program check method for a microcomputer system, characterized in that a data setting device is provided to enable the microcomputer to calculate and display checksum data or to set checksum data.