KR0166791B1 - Program memory testing device and method for one chip microcomputer - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-chip microcomputer, and more particularly, to an apparatus and method for testing a program memory unit of a one-chip microcomputer which can reduce the test time by simultaneously testing a program memory unit and testing other functional blocks in progress.

The program memory unit test apparatus of the one-chip microcomputer of the present invention includes a central processing unit for controlling the entire system, an interrupt controller for controlling the interrupt function, a data memory unit for storing information about data, a main system, The program memory unit is connected to an on-line or off-line peripheral unit for input / output, a program memory unit for storing respective program information having a specific pattern, and an address bus line for switching by a first switching switch. An address counter means section for assigning an address to the checksum, a check sum calculation means section for calculating and storing all data of the designated address of the program memory section through a data bus line switched by the second switch; The first and second switch and address counter means And a test mode switching means for controlling and an input / output port for inputting or outputting the data of the whole data and the system-wide data of the check sum calculation means, and the method is switched to the test mode. The first step of performing a checksum sum of all the address data of the memory unit, the second step of executing the tests of each functional unit except the program memory unit while the first step is in progress, and the completion of the second step. And a third step of comparing the entire checksum data with the expected value and determining the good and bad according to the result.

Description

Program memory unit test apparatus and method of one-chip microcomputer

1 is a block diagram of a conventional one-chip microcomputer.

2 is a flow chart showing a conventional program memory unit test method.

3 is a block diagram of a one-chip microcomputer of the present invention.

4 is a flowchart illustrating a test method of a program memory unit of the present invention.

* Explanation of symbols for main parts of the drawings

30: interrupt controller 31: central processing unit

32: data memory section 33: peripheral device section

34: test mode switching means section 35: address counter means section

36: program memory section 37: check sum calculation means section

38: input / output port 39: data busline

40: address bus line 41: first switch

42: second switching switch

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-chip microcomputer, and more particularly, to an apparatus and method for testing a program memory unit of a one-chip microcomputer that can simultaneously test other functional blocks while testing a program memory unit, thereby reducing the test time.

Hereinafter, a program memory unit test of a conventional one chip microcomputer will be described with reference to the accompanying drawings.

1 is a block diagram of a conventional one-chip microcomputer, and FIG. 2 is a flowchart illustrating a conventional test method of a program memory unit.

First, as shown in FIG. 1, the conventional one-chip microcomputer includes an interrupt controller 1, a central processing unit 2, a data memory unit 3, a program memory unit 4, a peripheral unit 5, and input / Each of the above functional units is structurally and functionally interconnected through an address busline 7 and a data busline 8.

The one-chip microcomputer configured as described above is subjected to a test for screening good and defective products.

In the test, data is applied to each functional unit through the input / output port 6 and the data bus line 8, and the result is read into the input / output port 6 to determine whether it matches the expected value. Done.

In the program memory section 4, program data is coded differently depending on the intended use.

At this time, it is tested whether the appropriate information is coded in the program memory section 4.

The above test method will be described with reference to FIG. 2, which is a flowchart illustrating a conventional program memory test method.

First, the address of the program memory section 4 It is designated as a address and the data of the program memory section 4 of the address is outputted to the input / output port 6, and the output data is compared with the expected value. Will be.

If the output data matches the expected value, if the address is increased by one address and the above test continues and there is no problem until the end address, the one-chip microcomputer processes the product and finishes the test.

However, in the program memory unit test apparatus and method of the conventional one-chip microcomputer as described above, since each of the other functional units of the one-chip microcomputer cannot be tested when the program memory unit 4 is tested, the test time according to the increase in the capacity of the program memory unit There was a problem that the increase of and the increase of the test cost occurred.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and it is possible to simultaneously perform a test of a program memory unit or a test of each block of a different function at the same time, thereby reducing test time and increasing costs accordingly. An object of the present invention is to provide an apparatus and method for testing a program memory part of an efficient one chip microcomputer.

The program memory unit test apparatus of the one-chip microcomputer of the present invention for achieving the above object includes a central processing unit for controlling the entire system, an interrupt controller for controlling the interrupt function, a data memory unit for storing information about the data; Through a peripheral device connected to the main system online or offline to perform input / output, a program memory unit for storing respective program information having a specific pattern, and an address bus line switched by the first switching switch. A check sum calculation for calculating and storing all data of the designated address of the program memory unit through an address counter means unit for assigning an address to the program memory unit and a data bus line switched by a second switch; Means section, the first and second selector switch and address And a test mode switching means unit for controlling the counter counter unit, and an input / output port for inputting or outputting the overall port data of the check sum calculation unit and the data of the entire system. The test method of the program memory unit of the microcomputer includes a first step of switching to a test mode to check sum of all address data of the program memory unit, and testing of each functional unit except for the program memory unit during the first step. And a third step of confirming the completion of the execution of the second step, comparing the checksum total data with an expected value, and determining a good or defective product according to the result. .

The program memory unit test apparatus and method of the one-chip microcomputer of the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram of a one-chip microcomputer of the present invention, and FIG. 4 is a flowchart showing a test method of a program memory unit of the present invention.

First, the program memory unit test apparatus of the one-chip microcomputer of the present invention, as shown in FIG. 3, provides information on the interrupt controller 30 for controlling the interrupt function, the central processing unit 31 for controlling the entire system, and data. A data memory unit 32 for storing, a peripheral unit 33 for input / output connected to the main system online or offline, a program memory unit 36 for storing respective program information having a specific pattern, and a first Switching operation by the address counter means unit 35 which assigns an address to the program memory unit 36 via the address bus line 40 which is switched by the switching switch 41, and the second switching switch 42. A check sum calculation unit 37 for calculating and storing all data of the designated address of the program memory unit 36 through the data bus line 39; The test mode switching means 34 for controlling the two-switch switch 41, 42 and the address counter means 35, the port output of the entire data of the checksum calculation means 37, and the system-wide data. And an input / output port 38 for inputting or outputting.

At this time, the components are structurally and functionally interconnected by the address busline 40 and the data busline 39.

Referring to the operation of the test device of the program memory unit of the one-chip microcomputer of the present invention configured as described above are as follows.

As shown in FIG. 4, which is a flowchart illustrating a test method of the program memory unit of the present invention, when the test mode switching unit 34 is set by applying data through the input / output port 38 (401), the test mode switching is performed. The output of the means section 34 enables the address counter means section 35, and the first switching switch 41 connects the output terminal of the address counter means section 35 and the input terminal of the program memory section 36 to the address bus. Control to be connected via the line 40.

The second switching switch 42 controls the output terminal of the program memory unit 36 and the input terminal of the check sum calculation unit 37 to be connected through the data bus line 39.

The address counter means section 35 enabled by the setting of the test mode switching means section 34 sets the address. The counter starts counting by incrementing by one from the street (402).

The counter value assigns an address to the program memory unit 36, and the data of the designated address is sequentially calculated and stored by the check sum calculation unit 37 (403, 404, 405).

When the test of the program memory unit 36 proceeds, the test of the specific block except for the program memory unit 36 is performed 406 and 407.

When the test of the specific block except for the program memory unit 36 is completed (408), the entire data of the checksum calculation unit 37 is ported out through the input / output port 38 (409). The comparison is made to determine whether good or bad (410).

If the above result is bad, an analysis test for searching for a bad address by user selection is performed (411).

The analysis test resets the test mode switching unit 34 (412), sequentially outputs the data of the program memory unit 36 according to the designated address (414), and compares the expected value with the expected value (415). The bad address is checked (416, 417, 418).

The program memory unit test apparatus and method of the one-chip microcomputer according to the present invention increases the test time due to the large capacity of the program memory unit by performing parallel testing of each function block except the program memory unit during the test of the program memory unit. To reduce test costs.

Claims (3)

A central processing unit for controlling the whole system, an interrupt controller for controlling the interrupt function, a data memory unit for storing information about data, a peripheral unit connected to the main system online or offline to perform input and output, A program memory section for storing respective program information having a specific pattern, an address counter means section for addressing the program memory section via an address busline switched by the first switching switch, and a second switching switch. A test sum calculation unit for calculating and storing all data of a specified address of the program memory unit through a data bus line operated by a switching operation, and a test mode for controlling the first and second switching switches and the address counter unit. The switching means section and the whole check sum calculation section; Program memory unit test apparatus for a one-chip microcomputer characterized in that it comprises a port output of the data and the input / output port for inputting or outputting the system-wide data. A first step of switching to the test mode to check sum of all address data of the program memory unit; a second step of performing tests of the respective functional units except for the program memory unit during the first step; And a third step of confirming completion of the second step, comparing the checksum data with the expected value, and determining the good quality or the poor quality according to the result. . The one-chip microcomputer according to claim 2, wherein when the result of the third step is processed as a defective product, an analysis test frame for retrieving the defective address by resetting the test mode switching unit is selected by the user. Program memory part test method.