Data transfer apparatus with channel controller and transfer controller capable of slave and standalone operation

A data transfer control apparatus includes a channel controller and a transfer controller. The channel controller receives, prioritizes and queues data transfer requests. The transfer controller includes separate control of data source and data destination in a data transfer corresponding to the data transfer requests. The transfer controller includes a data transfer program register and active source and destination registers. The transfer controller operates from the active source and destination registers. Upon completion of a data transfer the transfer controller writes data transfer parameters from the data transfer program register to the active source and destination registers.