| 摘要 |
<p>PURPOSE:To obtain the function of a high level by a few terminals, by forming a signal for accessing the external memory, controlling the coupling of LSI and the external memory by this signal, and executing to send and receive a signal by effectively making the best of the terminal provided in LSI. CONSTITUTION:The output control circuit OD connected to the input/output terminal terminal 12 and the circuit RW for giving a read/write timing, connected to the output terminal 13 are provided as a circuit for forming a timing signal by which the operation time for reading a signal of the external memory, in the 1 chip LSI circuit which transfers a signal between the micro-computer and the external memory. And the signal from the external memory is read through the input terminals 3-10 of LSI in a state that this timing signal has been provided to the external memory from the output terminal 13, the timing signal is inverted in the gate circuit IG, and by separating the external memory in the aforesaid status, the operation is executed by a signal which has divided the clock frequency from the internal oscillator CG.</p> |
