发明名称 Integrated CPU and DMA with shared executing unit
摘要 A data processor controller for a microprogramming system is constructed with a single operation execution unit serving both a microprocessor and a peripheral device such as a direct memory access controller. In addition to the single operation execution unit, the controller includes a micro-memory which stores micro-instructions for controlling both the microprocessor and the peripheral device, and address registers, multiplexers and decoders integrated into a single device. Different ROM address registers in the controller are separately assigned to provide an address decoder with addresses of selected memory locations in the micro-memory containing the micro-instructions for the microprocessor and the peripheral device, thereby enabling the controller, through multiplexing between the address registers, to use the arithmetic execution unit, counter and bus interface of the single operation exeuction unit on a time sharing basis, for controlling the functions of both the microprocessor and the peripheral device.
申请公布号 US5005121(A) 申请公布日期 1991.04.02
申请号 US19890326472 申请日期 1989.03.20
申请人 HITACHI, LTD. 发明人 NAKADA, KUNIHIKO;AKAO, YASUSHI
分类号 G06F9/26;G06F9/22;G06F13/10;G06F13/28;G06F15/78 主分类号 G06F9/26
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