Data Transmission processing system having DMA channels running cyclically to execute data transmission from host to memory and from memory to processing unit successively

摘要

A data transmission processing system provided between a host unit and peripheral devices including at least a memory device and a processing device. The host unit outputs, to the transmission processing system, DMA transmission process request commands. The data transmission process system includes a DMA control unit, provided with a plurality of DMA channels, for cyclically selecting a DMA channel from the plurality of DMA channels in accordance with a predetermined priority, the plurality of DMA channels being allocated to processes with respect to the peripheral devices, and a DMA execution unit for carrying out a DMA transmission process for transmitting data output from the host unit to the memory device via a selected DMA channel corresponding to the memory device in data transmission timing of the host unit and a DMA transmission process for transmitting data stored in the memory device to the processing device via a selected DMA channel corresponding to the processing device in accordance with the DMA transmission process request commands supplied from the host unit.