Patent ID: 7610581

Claim:
A data processing system capable of running a plurality of operating systems under the control of a control program executed on a central processing unit, said data processing system comprising a channel device for transmitting and receiving data to and from an I/O device, wherein: said channel device includes a plurality of channel device identifiers each indicative of a medium for transmitting and receiving data to and from the I/O device, said control program includes means for assigning one operating system on said system to each of the plurality of channel device identifiers, and said channel device further includes an input/output processing control means for independently controlling transmission and reception of data for input/output processing initiated from a certain operating system for each of the channel device identifiers to which the operating systems are assigned, said input/output processing control means controlling the transmission and reception of data for the plurality of operating systems, and wherein: said channel device includes a plurality of control registers respectively storing one of the channel device identifiers for the respective operating systems on said system to control said channel device, said control program includes means for assigning one operating system to each of said control registers, and each of said control registers is controlled by the operating system assigned thereto, and each of the operating systems is arranged to communicate with the I/O device according to a channel device identifier having been stored in the control register assigned to corresponding one of the operating systems.