Patent ID: 6463482
Filing Date: 2002-10-08
Classification: G06F

Abstract:
A method of controlling data transfer between external peripheral devices connected to a microprocessor through a data bus, said method comprising the steps of:monitoring a data transfer instruction on said data bus; when an execution instruction for MPC transfer is issued, measuring a time period over which said data bus is to be occupied with said MPC transfer, said MPC transfer being data transfer in accordance with directions from said microprocessor; when said data bus is to be occupied with said MPC transfer for a predetermined length of time or longer, performing said MPC transfer instruction after the completion of DMA transfer without suspending said DMA transfer, said DMA transfer being data transfer between said external peripheral devices; and when said data bus is to be occupied with said MPC transfer for less than said predetermined length of time, suspending said DMA transfer, performing said MPC transfer, and resuming said DMA transfer after completion of said MPC transfer.