公开(公告)号：US3562711A

公开(公告)日：1971-02-09

申请号：US3562711D

申请日：1968-07-16

Applicant: IBM

Inventor： DAVIS ROBERT H ,  BOUDREAU PAUL E ,  HARRIS JERRY S

IPC: H04L1/00 ,  G08C25/00 ,  H04L1/10

CPC classification number: H04L1/0057

Abstract: A DEVICE FOR DETECTING CIRCUIT MALFUNCTIONS IN CERTAIN LINEAR SWITCHING CIRCUITS OPERATED IN SUCCESSIVE TIME PERIODS WHICH HAS A FIRST CIRCUIT FOR GENERATING A PREDICTED PARITY SIGNAL FOR EACH SUCCESSIVE TIME PERIOD, A PARITY CHECK CIRCUIT FOR GENERATING A SIGNAL INDICATIVE OF ACTUAL PARITY DURING EACH SUCCESSIVE TIME PERIOD, AND A COMPARATOR FOR COMPARING THE SIGNALS REPRESENTING THE PREDICTED PARITY AND THE ACTUAL PARITY DURING EACH SUCCESSIVE TIME PERIOD, THEREBY TO INDICATE ANY CIRCUIT MALFUNCTION DURING EACH SUCH SUCCESSIVE TIME PERIOD.

公开(公告)号：US3579200A

公开(公告)日：1971-05-18

申请号：US3579200D

申请日：1969-07-30

Applicant: IBM

Inventor： DAVIS ROBERT H ,  HARRIS JERRY S

IPC: G06F11/10 ,  G06F11/00 ,  G06F13/12 ,  H03M13/00 ,  G06F11/08 ,  H04L1/00

CPC classification number: G06F11/0763 ,  G06F13/124

Abstract: A data processing system including a plurality of terminals connected to a transmission medium for sending and receiving data and control signals between terminals is provided, and each terminal includes a master control connected by bus means having data lines and control lines to a plurality of satellite controls and input-output devices. A first parity checking device checks the parity of the signals on the control lines from each satellite to the master control, and a second parity checking device checks the parity of the signals on the control lines from the master control to the satellite controls. Even or odd parity may be used, but odd parity is preferred. Each satellite control includes a plurality of circuits interconnected to perform the control function of such satellite control, and each one of the plurality of circuits has an output line connected to an odd number of other such circuits, whereby a malfunction in any one of said plurality of circuits affects an odd number of control lines from such satellite control which thereby forces the first parity checking device to detect a malfunction. Each satellite control, for the odd parity case, supplies a control signal on a single given control line when it is not active, whereby the first parity checking device checks the status of each satellite control during both the active and the inactive states.