| 摘要 |
PURPOSE:To facilitate the changeover of a count source of a timer. CONSTITUTION:A timer value is set to a timer 1 from a reload register 2 and the timer 1 counts the time up to the timer value. After the count of the timer 1 is finished, an overflow signal 5 is outputted. A count source reload register changeover device 7 selects a switch every time the overflow signal 5 is received. Upon the receipt of the overflow signal, the reload register 6a or 6b outputs count resource changeover information and switches the count source changeover device 4 to supply a count source to the timer 1 from optional count sources 3a-3c. Thus, the changeover of the count sources is facilitated and the operating speed of the timer 1 is quickened. |
