DATA TRANSFER CONTROLLER

摘要

PROBLEM TO BE SOLVED: To transfer data fast between an LSI and an external memory and between data processing units in the LSI by providing a transfer control means which inputs and outputs data to and from data processing units via a data base in synchronism with a basic operation clock, etc. SOLUTION: A system control unit 4 outputs a transfer request signal to a data transfer control unit 6 in synchronism with the basic operation clock. Any of the data processing units 2-5 performs data transfer with the external memory 7 through a single data bus 8 by making only the Low section of the basic operation clock effective on an internal data bus 8. Further, the High section of the basic operation clock is used for data transfer with the data processing units 2-5 in the LSI. Consequently, the data transfer in the LSI can be performed by the single bus even during the data transfer with the external memory 7, so that the data can be transferred fast and processed fast.