HIGH-SPEED, HIGH-CAPACITY, FAULT-TOLERANT, ERROR-CORRECTING STORAGE SYSTEM FOR BINARY COMPUTERS

摘要

This invention provides disk driveaccess control apparatus for connectionbetween a host computer (10) and a pluralityof disk drives (16) to provide anasynchronously operating, high-speed,high-capacity, fault-tolerant, error-correctingstorage system. It also providesincreases in performance over earlierversions thereof. There are a plurality ofdisk drive controller channels (46)connected to respective ones of the diskdrives and controlling transfers of datato and from the disk drives, each of thedisk drive controller channels includes acache/buffer memory (48) and a micro-processorunit (50). An interface anddriver unit (42) interfaces with the hostcomputer (10) and there is a central cache memory (54). Cache memory controllogic controls transfers of data from the chache/buffer memory (48) of the plurality of disk drive controller channels (46) tothe cache memory (54) and from the cache memory(54) to the cache/buffer memory (48) of the plurality of disk drive controllerchannels (46) and from the cache memory (54) to thehost computer (10) through the interface and driver unit (42). A centralprocessing unit (60) manages the use of the cache memoryby requesting data transfers only of data not presently in the cache memory(54) and by sending high level commands to the diskdrive controller channels (46). A first (data) bus (64) interconnects theplurality of disk drive cache/buffer memories (48), theinterface and driver unit (42), and the cache memory (54) for the transfer ofinformation therebetween and a second (informationand commands) bus (52) interconnects the same elements with the centralprocessing unit (60) for the transfer of control andinformation therebetween.