| 摘要 |
<p>PURPOSE:To execute plural number of times of continuous refresh in one acknowledge signal period by counting a refresh pulse with a refresh request stopping counter, and outputting a refresh stopping signal when a count value reaches a prescribed value. CONSTITUTION:A refresh timer 1 outputs a refresh request at a constant cycle, and an SR type FF is set, and an acknowledge signal ACK is outputted from a bus arbitor 3, and a first control circuit 6 makes a refresh address counter 4 perform a count operation in the period of the signal, and also, outputs a refresh pulse REF for acquiring bus for refresh. The pulse REF is counted with the refresh request stopping counter 8, and when the count value coincides with a preset value, the content of the counter 8 is set at 0 with a second control circuit 9, and the output of the counter 8 goes to the refresh stopping signal, then, the FF 2 is reset. Therefore, a prescribed number of times of continuous refresh can be performed in one period of the signal ACK, and efficient refresh can be performed in point of time.</p> |
