| 摘要 |
PURPOSE:To detect failures of each transmission line and malfunction of an input controller itself, by using selection signals used for the scanning of input signals also as the input signals themselves. CONSTITUTION:Selection signals (a)-(c) formed from lower 2 bits of a six-notation counter 3 are applied to a multiplexer as input signals, when the most significant bit(MSB) (d) of the counter 3 is 1. That is, when the MSB (d) is 0, the multiplexer 5 inputs the state of each switch to a controller 6 according to the selection signals (a)-(c). When the MSB (d) is 1, the multiplexer 5 inputs the selection (a)-(c) to the controller 6 as the detection of malfunction. In the controller 6, failures of transmission lines and malfunction of the input controller itself can be detected by checking the detection signal. |
