JPH1055290A - Failure detection method for program by emulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a failure after product mass-selling by issuing an alarm to a user in the case that a second instruction group is executed before a first instruction is executed. SOLUTION: It is detected that an instruction A is not executed before executing an instruction group B and instruction omission on a program is automatically discovered. That is, a target MCU 11 reads and executes a user program stored in an emulation memory 12. At this point, an instruction A comparator circuit 13 and an instruction group B comparator circuit 14 respectively detect that the target MCU 11 executes the instruction A and the instruction group B, and when the instruction A comparator circuit 13 and the instruction group B comparator circuit 14 respectively detect the instruction A and the instruction group B, detection signals 13a and the detection signals 14a are outputted. In such a manner, in the case that the second instruction group B is executed before the first instruction A is instructed, the alarm is issued to the user.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a program defect detection method using an emulator which can automatically detect a simple instruction omission and prevent a defect after mass production of a product.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a state in which a program of a microcomputer built in, for example, an electric appliance is developed. Reference numeral 1 denotes an electric appliance as a device under development controlled by a microcomputer 1a; Reference numeral 2 denotes an emulator for controlling the electric appliance 1 instead of the control operation by the microcomputer 1a to confirm the operation of the electric appliance 1 in developing a program of the microcomputer 1a of the electric appliance 1, and 3 denotes an emulator 2 and a communication line 4.
And a host machine 5 serving as a personal computer or a workstation for controlling the emulator 2, and emulator control software (hereinafter referred to as control software) operating on the host machine 3.

Next, the operation will be described. After creating a program for the microcomputer 1a of the electric appliance 1, it is checked whether the electric appliance 1 operates normally by using the emulator 2 which operates based on the control software 5. That is, a defective portion of the program of the microcomputer 1a of the electric appliance 1 is detected, and when a defective portion is found, the defective portion of the program of the microcomputer 1a is corrected by the host machine 3.

However, when a program is developed using the emulator 2, there is a case where a failure in detecting a defective portion occurs due to insufficient inspection of the program. In particular, there are many problems due to simple contents such as forgetting to initialize the flag of the microcomputer 1a or memory, and even if such a simple mistake is found after mass production of the product, serious trouble occurs. Is a factor.

[0005]

Since the conventional method of detecting a program defect using an emulator is configured as described above, insufficient detection of the program may cause omission of detection of a defective portion due to insufficient program inspection. There were challenges.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and a method of detecting a program defect by an emulator which automatically detects a simple instruction omission and prevents a defect after mass production of a product. The purpose is to gain.

[0007]

According to a first aspect of the present invention, there is provided a method of detecting a program defect using an emulator.
When the mounted microcomputer executes the first instruction and the second instruction group affected by the execution of the first instruction, the first instruction is executed before the second instruction group is executed. Is determined, and if the second command group is executed before the first command is executed, an alarm is issued to the user.

According to a second aspect of the present invention, there is provided a method for detecting a defect in a program by an emulator, comprising detecting an instruction code read signal output at a timing at which a first instruction and a second instruction group are read from an emulation memory. By comparing the first instruction and the second instruction group read for program execution with the first instruction and the second instruction group to be detected in advance by a comparator, the first instruction and the second instruction group are compared. The execution of the instruction group is detected.

According to a third aspect of the present invention, there is provided a method for detecting a defect in a program by an emulator, wherein the first event detection circuit determines whether or not the second instruction group has been executed after the first instruction has been executed. At the same time, the second event detection circuit determines whether or not the second instruction group has been executed alone, and issues an alarm to the user.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a block diagram showing a method for detecting a defect in a program by an emulator according to a first embodiment of the present invention. In FIG. 1, reference numeral 11 denotes a target MCU as a microcomputer for which a user creates a program. And has an instruction A (first instruction) for initializing the target MCU 11 and an instruction group B (second instruction group) affected by the execution of the instruction A. An emulation memory 12 stores a program created by the user, and stores an instruction group corresponding to the target MCU 11.

An instruction A comparison circuit 13 detects whether the instruction A has been executed by the target MCU 11, an instruction group B comparison circuit 14 has detected whether the instruction group B has been executed by the target MCU 11, and 15 has an instruction. The first event detection circuit 16 detects that the instruction group B is executed after the execution of A, and the second event detection circuit 16 detects the single execution of the instruction group B.

Next, the operation will be described. The first embodiment detects that the instruction A is not executed before executing the instruction group B, and automatically detects a missing instruction in the program. First, the target MCU 11 reads and executes a user program stored in the emulation memory 12. At this time, the instruction A comparison circuit 13 and the instruction group B comparison circuit 14
1 respectively detects the execution of the instruction A and the instruction group B, and when the instruction A comparison circuit 13 and the instruction group B comparison circuit 14 detect the instruction A and the instruction group B, respectively, the detection signal 13a and the detection signal 14a Is output.

FIG. 2 is a block diagram showing operations of an instruction A comparison circuit and an instruction group B comparison circuit as an instruction comparison unit in the method for detecting a program defect by the emulator according to the first embodiment of the present invention. First, target MCU1
The instruction codes of the instruction A and the instruction group B read out from the emulation memory 12 for execution of the program by 1 are output to the data bus 21 of the target MCU 11. Then, the instruction code and the instruction code read signal 22 output from the target MCU 11 are input to the comparator 23.

The instruction code read signal 22 is a signal output at the timing when the target MCU 11 reads an instruction code from the emulation memory 12. Further, the instruction codes of the instruction A and the instruction group B to be detected are transferred from the host machine 3 to the emulator 2 in advance.
The data is stored in the latch 24. As shown in FIG. 2, when the instruction code read signal 22 is output from the target MCU 11, the instruction codes of the instruction A and the instruction group B on the data bus 21 of the target MCU 11 and the instruction code of the instruction
By comparing the instruction code executed by U11 with the comparator 23, the execution of the instruction A and the instruction group B can be detected. When the instruction A comparison circuit 13 and the instruction group B comparison circuit 14 detect the instruction A and the instruction group B, they output a detection signal 13a and a detection signal 14a.

When the first event detection circuit 15 receives the detection signal 13a and the detection signal 14a and detects a condition that the instruction group B is executed after the instruction A is executed, the detection signal 15a Is output. In the second event detection circuit 16, when the detection signal 15a and the detection signal 14a from the instruction group B comparing circuit 14 are input, the instruction group B is executed after the instruction A is executed when the execution of the instruction group B is detected. Is not detected at the same time, it is considered that the instruction group B has been executed alone, and the instruction group B
Is output to the emulator 2 (see FIG. 3) indicating that the program has been executed independently.

The output of the detection signal 16a is as follows.
Since the instruction group B affected at the time of execution of the initialization instruction indicates that it was executed before the initialization instruction A, the emulator 2 sends the detected event to the host via the communication line 4. The transfer to the machine 3 is reported to the user of the emulator 2.

As described above, according to the first embodiment, the instruction A comparison circuit 13 and the instruction group B comparison circuit 14 as the instruction comparison units, and the first event detection circuit 15 and the The second event detection circuit 16 detects that the instruction A has not been executed before executing the instruction group B, and automatically detects the omission of the instruction in the program, thereby preventing a problem after mass production of the product. And the like.

In the first embodiment, the target MC
Although the description related to the initialization instruction of U11 has been described,
The present invention is not limited to the initialization instruction, and can be used when it is necessary to execute another arbitrary instruction before executing an arbitrary instruction. In other words, the present invention can be applied to any combination of instructions, and can be used to detect missing combinations of instructions. Therefore, it is possible to obtain an effect that more program defects can be detected.

[0019]

As described above, according to the first aspect of the present invention, the mounted microcomputer executes the first instruction and the second instruction group affected by the execution of the first instruction. Sometimes, it is determined whether or not the second instruction group has been executed after the execution of the first instruction. If the second instruction group is executed before the first instruction is executed, Since the configuration is such that a warning is issued to the user, an omission of an instruction in a program is automatically detected, so that there is an effect that problems after mass production of the product can be prevented.

According to the second aspect of the present invention, when the instruction code read signal output at the timing of reading the first instruction and the second instruction group from the emulation memory is detected, the instruction code read signal is read for executing the program. Comparator compares the first instruction and the second instruction group with the first instruction and the second instruction group to be detected in advance, thereby detecting the execution of the first instruction and the second instruction group. With such a configuration, an omission of an instruction in a program is automatically detected, so that there is an effect that defects after mass production of the product can be prevented.

According to the third aspect of the present invention, the first event detection circuit determines whether or not the second instruction group has been executed after the execution of the first instruction, and the second event detection circuit. The circuit is configured to judge whether the second instruction group has been executed independently and to issue an alarm to the user, so that the omission of the instruction in the program is automatically detected. Has the effect of being able to prevent the problem beforehand.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a method for detecting a program defect using an emulator according to a first embodiment of the present invention;

FIG. 2 is a block diagram showing operations of an instruction A comparison circuit and an instruction group B comparison circuit as an instruction comparison unit in the method for detecting a program defect by the emulator according to the first embodiment of the present invention;

FIG. 3 is a configuration diagram showing a state when a program of a microcomputer built in, for example, an electric appliance is developed.

[Explanation of symbols]

11 Target MCU (microcomputer), 1
2 emulation memory, 15 first event detection circuit, 16 second event detection circuit, 22 instruction code read signal, 23 comparator.

Claims (3)

[Claims] 1. The microcomputer mounted is a first microcomputer.
When executing the first instruction and the second instruction group affected by the execution of the first instruction, it is determined whether or not the second instruction group has been executed since the execution of the first instruction. A method of detecting a program defect by an emulator that issues an alarm to a user when the second instruction group is executed before the first instruction is executed. 2. When detecting an instruction code read signal output at a timing at which a first instruction and a second instruction group are read from an emulation memory, the first instruction and the second instruction read out for executing a program are detected. The second
The execution of the first instruction and the second instruction is detected by comparing a first instruction and a second instruction to be detected in advance with a comparator by using a comparator. A method for detecting a program defect using the emulator according to 1. 3. The first event detection circuit determines whether a second instruction group has been executed after the execution of the first instruction, and the second event detection circuit judges whether the second instruction group has been executed.
3. The method according to claim 2, further comprising: determining whether the set of instructions has been executed independently and issuing an alarm to a user.