| 摘要 |
<p>PURPOSE: To provide a timer circuit incorporated one-chip microcomputer which can start and stop counting operation without considering the state of the timer. CONSTITUTION: This is the built-in timer control method of the one-chip microcomputer having the built-in timer which starts counting after a relative register 3 is initialized and stops counting automatically after a certain sequence is executed. To rewrite the data in the relative register 3, a write instruction is executed twice successively for the same address. When a 1st write instruction is executed, only the gates for the bits of the data in the relative register 3 which should be rewritten among gates G0-G7 of a control gate circuit 4 are opened. When a 2nd write instruction is executed, data are written to the bits to be rewritten from an internal bus 2 through the gates which are opened with the 1st write instruction.</p> |
