JPS6381541A - Check system for program sequence - Google Patents

Abstract

PURPOSE:To detect malfunction before the execution of processing by generating a prescribed route flag and a route code in response to the program processing such as the program to be executed next being a process or a subroutine and collating the route flag and the route code so as to check the sequence. CONSTITUTION:When the next stage is a process, a serial ID part 12 of the route flag is modified to generate a new serial ID part 15 thereby generating the route flag. Moreover, when the next stage is a subroutine, the subroutine code is set to a subroutine ID part 14 of the route flag. In this case, the serial ID parts 12, 15 are unchanged. If an error takes place in the program sequence, since the storage location of the route flag is constant independently of the process, an erroneous route flag 18 is to be generated. In checking the program sequence, the process references the serial ID part 12 of the route flag and the subroutine references the subroutine ID part 11 and the result is collated with the route code 13 given to each process and subroutine.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is directed to malfunctions caused by runaway microprograms,
This paper relates to a microprogram sequence check method to prevent data corruption.

[Conventional technology]

Conventionally, there have been two methods for checking microprogram sequences:

One is to use the execution result of a microprogram as status or flag information, and detect malfunctions during execution based on this status or flag information.

The other is to perform a parity check etc. when reading the program from the ROM that stores the microprogram.
Detects microprogram abnormalities.

[Problem that the invention seeks to solve]

However, in conventional program sequence checking methods, malfunctions are detected after the processing has been executed, resulting in unnecessary execution and low efficiency.

Another problem is that separate hardware is required to perform parity checks and the like.

The present invention has been made to solve the above-mentioned problems, and aims to provide a program sequence check method that detects malfunctions before execution of processing without adding hardware.

[Means for solving problems]

For this reason, the present invention generates a predetermined route flag and route code depending on the processing of the program, such as whether the program to be executed next is a process or a subroutine, and checks the sequence by comparing the generated route flag and route code. It is characterized by performing the following.

[Effect]

In this invention, a predetermined route flag and route code are generated according to the processing of the program.

Then, the generated route flag is compared with the route code to perform a program sequence check.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Temperature reading ω is a configuration diagram showing an embodiment of the present invention, and in the figure, 11
is the subroutine ID part of the root flag to perform a sequence check at the start of processing, 12 is the serial ID part of the root flag to perform a sequence check at the start of processing, and 13 is attached to each process to perform a sequence check. Lou) Co-1', 14
is the root flag subroutine I at the end of processing
D part, 15 is the serial ID part of the root flag at the end of processing, 16 is each process of the microprogram,
17 is a subroutine, and 18 is a route flag consisting of a subroutine ID section 14 and a serial ID section 15.

Next, the operation will be explained.

If the next stage is a process, the serial ID section 12 of the root flag is transformed, a new serial ID section 15 is created, and a root flag is generated.

If the next stage is a subroutine, the subroutine code is set in the subroutine ID section 14 of the route flag.

In this case, there is no change in the serial ID section 12.15. If an abnormality occurs in the program sequence, an incorrect root flag 18 will be generated because the storage location of the root flag is fixed regardless of the process.

When checking the sequence of a program, the process refers to the serial ID section 12 of the root flag, and the subroutine refers to the subroutine ID section 11, and the sequence is checked by comparing it with the root code 13 attached to each process and subroutine.

Although the microprogram sequence check according to the present invention has been described in the case of firmware, the same effects as in the above embodiments can be obtained for general software as well.

〔Effect of the invention〕

As described above, the present invention generates a predetermined route flag and route code depending on the processing of the program, such as whether the program to be executed next is a process or a subroutine, and collates the generated route flag and route code to sequence the sequence. Since this check is performed, there are no changes to the hardware configuration, and malfunctions can be detected quickly.

[Brief explanation of the drawing]

The trick is a configuration diagram showing an embodiment of the present invention. In the figure, 11.14 is a subroutine ID section, 12.
15 is a serial ID section, 13 is a root code, 16 is a process, and 17 is a subroutine.

Claims (1)

[Claims] In order to prevent malfunctions and data corruption due to program runaway, the program sequence check method uses predetermined route flags and routes according to program processing, such as whether the next program to be executed is a process or a subroutine. A program sequence checking method characterized by generating a code and checking the sequence by comparing the generated root flag with the root code.