| 摘要 |
A data store and retrieval system is disclosed in which a pair of RAM buffer memories are coupled to a CCD page main memory to provide high-speed read/write access by a computer to the main memory. Each buffer memory has stored therein a page of data transferred from the CCD main memory. Compare means included in the system compares the page address requested by the computer with the page address stored in the buffer memories. If a comparison is found, the designated buffer memory is accessed for the requested data. Both read/write access is available under these conditions. If a no comparison is found, logic circuits located in the system using the requested page address transfer the page in which the requested address is located from the CCD main memory to the RAM buffer memories for access by the computer. If a write operation had occurred on a page stored in the buffer memories, the altered page is transferred back to the CCD main memory before a new page of data is transferred to the buffer memory other than the buffer memory in which the previous page address was found. |
