In the computer system the communication bus control device and the bus control manner

摘要

PURPOSE: To provide a data processing system to use a priority interruption for changing the control of a communication bus. CONSTITUTION: A data processor having a direct memory access controller(DMAC) is interrupted by a priority signal and changes the bus control of the communication bus in a system. A central arithmetic unit reports the highest priority among interruption orders accumulated in the DMAC. While using a mask value, the DMAC selectively separates the interruption and the selected interruption removes the bus control from the DMAC.