Direct Memory Access (DMA) is a technique for transferring blocks of data between system memory and peripherals without a processor (e.g., system CPU) having to be involved in each transfer. DMA not only offloads a system’s processing elements, but can transfer data at much higher rates than processor reads and writes.
Scatter-Gather DMA augments this technique by providing data transfers from one non-contiguous block of memory to another by means of a series of smaller contiguous-block transfers. The Lattice Scatter-Gather DMA Controller core implements a configurable, multi-channel, WISHBONE-compliant DMA controller with scatter-gather capability.