JPS5835287B2 - computing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a computing device such as a microcomputer with a built-in memory.

Microcomputers, especially one-chip microcomputers, have arithmetic circuits and ROM inside the package.
(Read 0nly Memory), RAM (R
It has built-in memory such as andom Access Memory).

In such microcomputers, even if the circuit format of the arithmetic circuits and the like is exactly the same, only the contents of the ROM often differ depending on the application.

In such cases, microcomputer manufacturers usually mark the model number on the surface of the package depending on the circuit type, and rarely also write the type of application.

Therefore, manufacturers manage microcomputers by placing them in separate containers for each purpose, but in order to separate the microcomputers through acquisition, there is a possibility that a container containing a microcomputer for one purpose may be mixed with a microcomputer for another purpose. It will be done.

In this state, when the completed microcomputer is tested using a test program specific to its intended use, the test program is not suitable for the microcomputer that happened to be mixed in, even though the microcomputer functions are complete. The present invention has been made in view of these points, and it is an object of the present invention to provide a computing device that can accurately identify the computing device with a simple configuration. The purpose is to

Such a feature of the present invention is that in a computing device with a built-in memory, identification data of the computing device is stored in a partial area of the memory, and a plurality of test programs prepared in advance are executed based on the identification data. A selection signal is output, a test program for the computing device is selected from among the plurality of test programs, and the computing device is tested by the test program.

The present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing the configuration of a computing device related to the present invention.

In the figure, 1 is a computing device, 2 is an instruction decoder, 3 is a control unit, and 4 is a ROM.

5 is a RAM 16, a register, 7 is an arithmetic unit, 8 is an output-only port, and 9 is an input/output port.

An outline of the operation of the computing device 1 is as follows.

That is, various instructions stored in the ROM 4 are decoded by the instruction decoder 2 and input to the control unit 3.

Upon receiving this command, the control unit 3 controls each functional unit within the computing device 1 to perform an operation according to the command.

On the other hand, external data is input from input/output port 9,
It is stored in RAM 5 or in RAM in arithmetic unit 7.
An operation is performed on the data read from M5, and the result is accumulated in register 6 and then stored in RAM 5 or output directly from output-only port 8.

In the computing device according to the present invention, data for identifying the computing device is written in an area 4' of a built-in memory, such as a ROM 4, where no information is written.

Therefore, when performing a trial test of this computing device, the computing device 1 is switched to a mode that directly reads the contents of the ROM, outputs this identification data via path a, and identifies the type. Tests can be performed accurately using a test program.

FIG. 2 is a block diagram showing an example of a testing system for a computing device using the present invention.

Now, identification data is read from the ROM of the computing device 1 and input to the decoder 21.

When there is input data, the decoder 21 stores it in the storage device 2.
Various test programs 23 to 2 stored in 2
6 selection signal.

Therefore, if the identification data read from the ROM of the computing device 1 corresponds to, for example, the test program 23, the decoder 21 outputs a selection signal for the test program 23, so that the test program 2
3 is read out and stored in the memory 28 of the control device 21.

The control device controls the test device 29 based on the accumulated test program 23, and the test device 29 controls the calculation device 1.
Test conditions according to the type of this computing device are applied to the calculation device.

Further, the computing device 1 provides an output corresponding to the input conditions to the testing device 29, and the testing device 29 determines whether the computing device 1 is good or bad based on this output, and displays a display to that effect.

Such a test system allows testing of computing devices to be performed automatically.

As explained above, according to the present invention, in order to store identification data for identifying the computing device in an empty area of the memory in a computing device with a built-in memory, it is possible to store identification data for identifying the computing device without error when testing the computing device. Since the test program is selected according to the type of computing device, it is possible to avoid a situation where the test program is determined to be defective because it is of a different type even though the function is complete. In the above embodiment, the identification data is stored in the ROM, but it may be stored in another memory such as a RAM.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of a computing device according to the present invention, and FIG. 2 is a diagram showing an example of a testing system for computing devices to which the present invention is applied. In the figure, 1 is a computing device, 4 is a ROM, 5 is a RAM, 2
3 to 26 indicate test programs.

Claims (1)

[Claims] 1. In a computing device with a built-in memory, identification data of the computing device is stored in a partial area of the memory, and based on the identification data, a selection signal of a plurality of test programs prepared in advance is outputted, and the plurality of test programs are outputted based on the identification data. Of the test programs,
A computing device characterized in that a test program for the computing device is selected and the computing device is tested by the test program.