| 摘要 |
<p>PROBLEM TO BE SOLVED: To make it possible to process both data transfer control on an external bus of a microcomputer and CPU operation such as an access to an internal bus by a built-in CPU in parallel while minimizing the increment of the physical/ logical scale. SOLUTION: A microcomputer 1 including a CPU 2 in its inside is provided with a 1st data transfer device 4 for controlling direct memory access transfer on external buses EDBUSA, EABUS of the microcomputer 1 and parallel execution of an internal bus access by the CPU 2 or the like and external data transfer control by the device 4 is made possible. An internal bus access by the CPU 2 and an external access by the device 4 are collectively controlled by an external bus controller 121. Consequently, the transfer of data on the external bus by the device 4 and instruction execution or the like using the internal bus by the CPU 2 can be executed in parallel.</p> |
