System for loading a current buffer desciptor register with a value different from current value to cause a previously read buffer descriptor to be read again

摘要

In a microcontroller employing a buffer descriptor ring direct memory access (DMA) unit, transmission of a packet can be split between multiple buffers. If an error occurs during the transmission of one of the buffers, the buffer descriptor ring DMA unit includes a provision that allows the software to reset the DMA channel to the first buffer containing the failed packet and to restart the transmission of the failed packet, rather than proceeding to the next packet.