Computer peripheral control apparatus

Claim 1

Peripheral control apparatus for connection with a computer bus structure for the transfer of data between one or more computer functional units connected to that bus structure and at least one computer peripheral device connected with the control apparatus, where each functional unit is any of a central processing unit, a memory unit, and another peripheral control unit, and where the bus structure includes first and second duplicative buses, said apparatus having the improvement comprising A. input means for receiving signals from any of said other functional units by way of any of said first and second buses and being conditioned by an applied control signal input thereto from said bus structure for responding to such signals on only a single one of said first and second buses, B. bus output means for applying signals, for transfer to any of said other functional units, identically to both of said first and second buses independent of the conditioning of said input means, C. device output means for connection to the peripheral device, D. first and second device control means, each of which is connected with said input means to receive signals from said bus structure and is arranged for providing identical operations in response to said received signals and for producing output signals in response to said operations, and at least said first of which is arranged to apply output signals to said bus output means and to apply further output signals to said device output means, and E. first fault-detecting means for detecting a first selected fault condition at least in signals transferred with respect to said device control means and responding to such a detected fault-condition to disable said bus output means from applying signals to either of said first and second buses.