Printer-tape data link processor with DMA slave controller which automatically switches between dual output control data chomels

摘要

A peripheral controller (data link processor) controls data transfers between a host computer and a plurality of tape peripheral units and a single printer peripheral unit. A master microprocessor commands three subordinate controllers to permit concurrent data transfers through a buffer memory in both the Read and the Write directions. A dual channel control from the master microprocessor actuates a DMA switch so that data transfers to/from the tape units can be controlled by switching on alternate control lines which regulate the data transfer operations.