| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the need for a mode-switching terminal by comparing the clock count value of a counter with a setting value being stored in a register and switching an internal circuit to a sub mode where a specified value being paired with the setting value indicates when both of them are equal. SOLUTION: Data for specifying sub modes 1, 2, and 3 are stored in the upper two bits of test registers 1, 2, and 3, and start addresses h' 10, h'20, and h'80 of a test cycle being executed in the sub modes 1, 2, and 3 are stored in lower 8 bits. When the count value of a clockϕof a counter 7 becomes equal to the start addresses h'10, h'20, and h'80 being inputted to comparators 8-10, high-level hit signals H1, H2, and H3 are outputted from the comparators 8-10. Multiplexers 24, 25, and 26 switch each internal circuit to the sub modes 1, 2, and 3 and performs a test, thus performing the test without any mode- switching terminal.
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