| 摘要 |
PURPOSE:To detect faults without increasing the number of signal lines by sending back an operation completion signal and an electric potential signal from each I/O device to an electronic computer through a common signal line and discriminating the voltage of the potential signal. CONSTITUTION:An electronic computer 1 sends an address signal, a controlling signal and a starting signal to an I/O device 2-1 e.g. through signal lines 1a, 1b, 1c, 1d, respectively. In case of normal operation, only the I/O device 2-1 responds to the computer 1 and the computer 1 discriminates the electric potential of a signal line 2b and processes these data as effective ones. If an I/O device e.g. responds to the computer 1 in error by any abnormal cause, the computer 1 discriminates the electric potential of the signal line 2b and processes the data read out from the line 2b as an error. |
