JPH09146787A - Test method for microprocessor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a test method for a microprocessor which shortens a test time and is used to test a different integrated circuit by providing test modes for an external mode, an internal mode, and an application program read mode. SOLUTION: A tested material 26 includes a tentative test mode switching unit 42 and a test control circuit 38 which belongs to the external mode, and the unit 42 is used for switching various test modes by selecting a test mode by receiving a external instruction that is inputted by a test machine 28 and enables other test modes to be increased on actual demand. Namely, test operation is advanced by making use of a three-way transmission line and when a partial test function for the internal mode is deficient or improper, a tentative external mode substitutes for test operation, thereby solving the problem of test incompleteness. Therefore, this test method not only increases the test efficiency, but also can test various different tested materials.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of testing an integrated circuit, and more particularly to a method of testing a microprocessor, which is a method for testing a microprocessor by a three-way transmission line of an external mode, an internal mode and an application program reading mode. , Those with high test efficiency.

[0002]

2. Description of the Related Art Integrated circuits are widely used in various fields from daily goods to high-tech products, and the quality of integrated circuits affects the performance of products. Therefore, functional testing of integrated circuits is important. Well-known integrated circuit test methods are divided into two types. FIG. 1 is a schematic diagram of one known integrated circuit test method, which is a test machine 10.
One more control signal is output to the material to be tested 12 to execute the test, and then one output signal output from the material to be tested 112 is compared with its expected value by the test machine 10 to confirm that the material to be tested is normal. It was to determine whether it can be used for.

Since the test machine 10 emulates the actual operation of the material 12 to be tested, as the function of the material 12 to be tested increases, the number of test items input to the tester 10 inevitably increases. The test time was longer and the test cost was higher.

When testing a microprocessor,
By means of the program unit and the state machine member programmed by the microprocessor, the function of the member is controlled by the internal program and outputs different under the operation of different programs. Therefore, if the traditional test method shown in FIG. 1 is adopted, a test difficulty occurs. That is, this is because each test item and test mode must be revised if the program programmed inside the microprocessor is revised.

For testing a microprocessor, a trader gives an instruction of each term from a test machine to the microprocessor for execution, and the microprocessor executes the result for forwarding to the test machine for comparison by the test machine. . However, if this technique is adopted, it is necessary to separate the original sequence and transmit both kinds of signals, which not only wastes time, but also the sequence at this time and the actual sequence are different, and the test succeeds. However, the actual application of the member may cause a phenomenon of failure, which affects the quality of the integrated circuit.

Further, FIG. 2 is a diagram showing another conventional method for testing an integrated circuit, in which the material under test 16 has a control circuit 18 for executing a decoding instruction and an instruction execution. Also, a signal is sent to the test machine 14. The original control signal source 24 is used for storing the application program, the control signal generator 22 is used for storing the test program and self-tests, and the test program is modified without following the application program. Is switched to the test program, the control signal generator 22 proceeds with a self-test on the material under test based on the programmed test program, and sends a signal of the completion of the test from the control circuit 18 to the tester 14 to obtain the expected result. It is used for comparison with the value, and thus for checking whether the function of the material under test is normal. During this test method, the programmed program of the control signal generator 22 is difficult to modify once it is programmed, which reduces the elasticity of the test. Furthermore, considering the cost, most of the space of one program memory is used for storing the application program, and the remaining space is used as the test program memory. It was difficult to complete the test, and its quality was affected.

As described above, the conventional microprocessor testing method is inconvenient and needs to be improved.

[0008]

SUMMARY OF THE INVENTION According to the present invention, commands are transmitted from a three-way transmission path of an external mode, an internal mode and an application program reading mode to perform a test operation to shorten the test time and to make an incomplete test. An object of the present invention is to provide a kind of microprocessor test method that is used for testing different integrated circuits and used to judge whether or not the functions are normal, while preventing the influence on the quality of the integrated circuits by the And

[0009]

The invention according to claim 1 is used for execution of different test modes, and sends the test result of the material under test to one test unit, and the test mode uses one test unit. The external command output by the test unit is input to the material under test waiting for the test, and the test path of the material under test is selected. In response to the external mode and selection of the external command input from the test unit, the test target is tested. Read the program code of the application program stored in the material under test in response to the selection of the internal mode and the external command input from the test unit, in which a self-test is performed by the programming program stored in the material and stored. It is characterized in that it includes an application program reading mode provided for comparison with the test unit.

According to the second aspect of the invention, the test step comprises:
The following steps a to e: a. Determine whether to proceed with the test operation, and if not, normally execute the program operation required by the material under test waiting for the test, and if so, enter the external mode stage. B. The external command input from the test unit is read in the external mode, and the test of the external mode is selected, or the test of various test modes is selected to proceed. C. When the test in the external mode is selected, the material under test waiting for the test decodes the external command input from the test unit, executes the command, and forwards the result to the test unit. D. After the test of the test function of each item is completed, the test unit inputs one external command, switches the test mode to the application program reading mode, and executes the test. E. Completion test, including the above.

According to the third aspect of the present invention, in the test step, when the internal mode is selected without selecting the external mode test in c, the internal mode is immediately entered and the test function for testing is selected and tested. And the results are forwarded to the test unit.

In the fourth aspect of the invention, when the internal mode test is selected in c in the test steps, the test program for programming the material under test waiting for the test includes at least one or more test mode functions. It is supposed to do.

According to the fifth aspect of the present invention, in the test step, c is not executed, one external command is input to the test unit in step d to switch to the application program reading mode, and the test is executed. There is.

According to the sixth aspect of the present invention, one test mode switching is performed, in which the material under test waiting for the test receives an external command input to the test unit, selects the test mode, and switches to various test modes. And a multiplexer that is electrically connected to the test control circuit and receives the output signal of the test control circuit, and a multiplexer that is electrically connected to the multiplexer to receive the output signal and decode the output signal. To execute the test and output the result of the test to the test unit, which is electrically connected to the control circuit and the multiplexer, which stores the test program programmed during the internal mode test and outputs the signal to the multiplexer. , One test program memory, used to store application program, application program read mode One application program memory that outputs a program code at the time of execution, and one memory reading device that is electrically connected to the multiplexer, reads the program code of the application program memory, and uses the test unit for comparison progress, Is included.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION A microprocessor testing method according to the present invention is such that an external command output from one test unit is input to a test material in a test standby state and a test path of the test material is selected. A mode and an external command input from the test unit are selected, and a self-test is performed by a test program that is programmed and stored in the material under test and an external command input from the test unit. In response to the selection of, the program code of the application program stored in the test material is read, and the different test modes including the application program reading mode, which are provided for the comparison performed by the test unit, are executed to test the test material. The result is sent to one test unit, and the method for testing a microprocessor of the present invention uses Different test paths and functions are planned according to the difference of the test items, and the inventor designs different items under the test function items, and expands and uses multiple test items under the available capacity space. it can.

[0016]

FIG. 3 is a system display diagram of an embodiment of the present invention. Among them, the test material 26 in the test standby state includes the test mode switching temporary device 42 and the test control circuit 28 belonging to the external mode, and the test mode switching temporary device 42 includes one test unit, for example, the test machine 28. The test mode is selected in response to an input external command and is used for conversion of various test modes, and other test modes can be increased according to actual demand. The test control circuit 38 controls the order of external commands input from the test unit, and also transmits the external commands to the control circuit 30 via the multiplexer 32. The control circuit 30 commands the decoding, executes the program command, and also transmits the signal to one test unit, for example, the test machine 28, so that the test unit proceeds with the comparison. Further, the memory 34, which is the original memory of the microprocessor, is used for storing an application program, and is used as a test program memory 36 for storing a test program. During the test, the memory of the microprocessor is switched to the test program memory 36, and the self-test proceeds by the test program programmed therein. The test program adopts a modular design, mainly the unary test function, and strengthens the elasticity of the test. other than this,
The ROM reading device 40 is supposed to read the program code of the application program memory 34, and tests whether the application program memory 34 outputs a normal command and executes the program operation, and sets the application program reading mode. Configure. The present invention uses a three-way transmission line to perform a test operation. In the case where a partial test function of the internal mode is insufficient or not applicable, the test operation is temporarily performed in the external mode. Resolve incomplete test problems. Therefore, this test method not only improves the test efficiency but also can test various different test materials.

Further, please refer to the control flow chart of the embodiment of the present invention in FIG. First, the power is turned on (44), and then it is determined whether to proceed with the test operation 46. If not, the material under test normally executes the program operation 48.
If it proceeds, the signal enters the test mode switching temporary unit of the external mode 50, and the test mode switching temporary unit reads the instruction f input from the outside world and selects 52 the test mode. If the external mode 50 is selected, the test control circuit of the external mode 50 transmits a signal,
After waiting for the completion of the test, the main control right is returned to the test mode switching temporary unit of the external mode 50 to continue the work. If the internal mode 58 is selected, the test program memory of the internal mode 58 is entered, and the test function to be tested is selected. After the completion of the test, the main control right is transferred to the test mode switching temporary unit of the external mode 50. , And continue the work, wait for the completion of the test of all the test functions to be tested in the external mode 50 and the spare internal mode 58, select the application program read mode 54, execute the command, and finish the test work. 56.

[0018]

According to the microprocessor testing method of the present invention, several different test paths and functions are planned according to different users, and the inventor designs different items under the test function item. In addition, multiple test items can be added and used under the available capacity space.

[Brief description of the drawings]

FIG. 1 is a diagram showing a known integrated circuit test method.

FIG. 2 is a diagram showing another test method for a known integrated circuit.

FIG. 3 is a system display diagram of the embodiment of the present invention.

FIG. 4 is a control flowchart of the embodiment of the present invention.

[Explanation of reference symbols] 10 ... Testing machine 12 ... Test material 14 ...
・ Test machine 16 ・ ・ ・ Material to be tested 18 ・ ・ ・ Control circuit 22 ・ ・ ・ Control signal generator 24 ・ ・ ・ Original control signal source 26 ・ ・ ・ Material to be tested 28 ・ ・ ・ Test machine 30 ・ ・
-Control circuit 32 ... Multiplexer 34 ... Application program memory 36 ... Test program memory 38 ... Test control circuit 40 ... ROM reading device 42 ... Test mode switching temporary storage device 44 ... Power on 46 ... Determine whether to proceed with test operation 48 ... Execute program operation normally 50 ... External mode 52 ... Select test mode 54 ... Application program read mode 56 ... ..End of test 58 ... Internal mode 60 ..
..Test function

Claims (6)

[Claims] 1. A test unit, which is used for executing different test modes and sends a test result of a material under test to one test unit, wherein the test mode waits for an external command output from one test unit. A self-test by a test program that is input to the material and selects the test path of the material to be tested, and an external mode and an external command input from the test unit, which are programmed and stored in the material to be tested. In response to the selection of the internal mode and the external command input from the test unit, the program code of the application program stored in the material under test is read and provided to the comparison performed by the test unit. A method for testing a microprocessor, characterized by including a read mode. 2. The test step comprises the following steps ae: a. Determine whether to proceed with the test operation, and if not, normally execute the program operation required by the material under test waiting for the test, and if so, enter the external mode stage. B. The external command input from the test unit is read in the external mode, and the test of the external mode is selected, or the test of various test modes is selected to proceed. C. When the test in the external mode is selected, the material under test waiting for the test decodes the external command input from the test unit, executes the command, and forwards the result to the test unit. D. After the test of the test function of each item is completed, the test unit inputs one external command, switches the test mode to the application program reading mode, and executes the test. E. Completion test, The method for testing a microprocessor according to claim 1, including the above. 3. When the internal mode is selected without selecting the external mode test in step c, the internal mode is immediately entered and the test function to be tested is selected, the test is executed, and the result is sent to the test unit. Forward, claim 2
The method for testing a microprocessor according to. 4. The microprocessor test of claim 3, wherein if the internal mode test is selected in step c, the test program programmed by the material under test awaiting the test includes at least one or more test mode functions. Method. 5. The microprocessor according to claim 2, wherein step c is not executed, step d is input to the test unit by inputting one external command to switch to the application program reading mode, and the test is executed. Test method. 6. The material under test waiting for a test receives an external command input to the test unit, selects a test mode, and switches to various test modes.
A test mode switching temporary device, one multiplexer electrically connected to the test control circuit and receiving an output signal of the test control circuit, and one multiplexer electrically connected to the multiplexer to receive the output signal A control circuit for decoding and executing the output signal and outputting a result of the execution to a test unit, and electrically connected to the multiplexer and storing a test program programmed at the time of the internal mode test, A test program memory for outputting a signal to the multiplexer; used for storing an application program; outputting a program code when executing the application program read mode;
An application program memory, and a memory reading device electrically connected to the multiplexer, reading a program code of the application program memory, and using the test unit for comparison progress;
The method for testing a microprocessor according to claim 1, comprising: