| 摘要 |
PURPOSE:To increase the type of an usable IC and to enhance a general-use characteristic by generating continuously an enable signal for a periphery IC to input always to the periphery IC. CONSTITUTION:A system clock signal 10 is impressed and frequency-divided to an interface circuit 22, an E signal 21 is taken out, and the E signal 21 continuous to a 68 type periphery IC 2 is always inputted. When the 68 type periphery IC 2 is selected and a microprocessor 1 executes the writing, the AND output of a writing signal 4 and a SELECT signal 12 is given to the buffer of a latch circuit 20, and the data are written by the trailing of the E signal. At the time of reading, the E signal 21 and the signal with the inverted polarity are impressed to the latch circuit 20, the AND output of a writing signal 6 and a SELECT signal 12 is given, the data are once latched to the latch circuit 20 by the trailing of the E signal 21 and thereafter, reading is executed.
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