Microprocessor system with memory device including a DMAC, and a bus for DMA transfer of data between memory devices

摘要

A processor system having a memory device including a (RAM) memory and a direct memory access controller (DMAC) and an internal bus switchably connected between the memory and the DMAC. A Bus Switch (multiplexer) within the memory device alternately establishes a first data transmission path over the system bus between the memory and an external processor, and a second data transmission path over the internal bus between the memory and the DMAC. The first data transmission path, when established through the Bus Switch, supports random access of the memory by the external processor. The second data transmission path, when established through the Bus Switch, supports a Direct Memory Access (DMA) between the RAM and an external storage device, e.g., a Nonvolatile Memory (NVM), connected to the DMAC while the processor has full and exclusive use of the system bus.