| 摘要 |
PROBLEM TO BE SOLVED: To provide a microcomputer capable of testing whether or not a functional signal in accordance with an instruction code stored in a ROM is generated by an instruction decoder correctly. SOLUTION: A program counter 2 is incremented by a control signal from a test mode control circuit 22, and the address of the ROM 4 is designated by an address signal generated from the counter, and a read out instruction code is held by an instruction code buffer 25, and also, the output of the instruction decoder 7 which decodes the instruction code is encoded to a corresponding instruction code by a functional signal encoder 26, and it is detected whether or not the instruction code coincides with the content of the instruction code buffer by a comparison circuit 28. |
