| 摘要 |
PURPOSE:To utilize effectively a function unit other than a CPU built in a microcomputer by making a function unit other than the CPU built in the microcomputer accessibly by a bus master at the outside of the microcomputer. CONSTITUTION:Bus masters except for the microcomputer output an address to an external address bus 7 and apply data transfer to elements at the outside of the microcomputer by utilizing an external bus control line 8 and an external data bus 9, output an address to an internal address bus 2 via a bus control circuit 6 in function units 5 except for the CPU built in the microcomputer and send a data by using an internal bus control line 3 and an internal data bus 4. Since the data is transferred between the function unit built in the microcomputer and the external element without the intervention of the CPU of the microcomputer in this way, the effect to high speed transfer is attained. |
