| 摘要 |
PURPOSE:To make competing circuit unnecessary and make perfect refreshing possible by dividing a D-RAM into two and making access alternately by the lowermost bit of an address line. CONSTITUTION:A D-RAM is divided into two to form banks A, B. When a microprocessor 1 accesses an address N and designates the bank A, a switching unit 9 selects an address bus 3, and a switching unit 10 selects a refresh address line 7 of the bank B, and D-RAM11 of the bank A is accessed and D-RAM12 of the bank B is refreshed. When an address N+1 is accessed, the switching unit 9 selects a refresh address line 6 of the bank A, and the switching unit 10 selects the bus 3, and the RAM11 is refreshed and RAM12 is accessed.
|
