| 摘要 |
PURPOSE:To surely detect fault by fixing the output of an output transistor TR circuit of a bus or a fault flag line to the low level at the time when the bus or the fault flag line is in the trouble mode and detecting disaccord between transmission data from the external and the output of a receiver to output the detection signal. CONSTITUTION:If a bus Bi (i=1 to (n)) is disconnected at a point P2 or P1, an output F in the high level is generated from an exclusive OR circuit XOR by the wraparound test because a terminal 1 is fixed to the low level, and the existence of fault is certainly detected, and it is reported to not only adjacent processors but also the other processors. As the result, fault flags (f) in all bus transcivers Ti go to the high level, and the output of a driver D, namely, the terminal 1 is fixed to the low level to stop data transmission. Thus, disconnection of the bus is surely detected. |
