| 摘要 |
PURPOSE:To eliminate the intervention of a central processor and to improve the accessing efficiency by storing the capacity exceeding the word constituting bit number of a 2-dimensional addressing memory to a region designated by an extension address with an extension mode designation. CONSTITUTION:A memory access/sequence control part 11 drives a Z address control part 21 in case an extension mode is designated. The part 21 compares the value of the extension address stored in a register 16 with the value of a Z address register counter having a partial up-down counting function of a register 18 when an access is over. When no coincidence is obtained through said comparison, +1 is given repetitively to the Z address register counter until the coincidence is obtained. The part 11 controls a register control part 12 when a data word is over, and the accessing address is renewed. |
