| 摘要 |
PURPOSE:To prevent a refresh discontinuation or the breakdown of memory contents by giving the switch control to the requests separated into access requests given from a bus and refresh requests given from a refresh control circuit respectively with a priority circuit. CONSTITUTION:A memory access request given from a bus via interface circuits 1a and 1b is sent to a priority circuit 6 after the bus is specified by a priority circuit 3. A refresh request given from a refresh circuit 2 is also supplied to the circuit 6, and therefore a read/write mode or a refresh mode is decided for an operation mode of a memory 5. The circuit 3 holds the priority until it finishes all operations; while the circuit 6 holds the priority only during the memory active. Then a memory control circuit 4 drives and performs prescribed operation the memory 5 with the output given from the circuit 6. |
