CONNECTING CONTROL SYSTEM

PURPOSE:To recover an input/output device from an abnormal condition without stopping a system as a whole by changing a DR control signal to the input/ output device from OFF to ON and initializing the input/output device fro a personal computer side. CONSTITUTION:A DR signal, which is the receiving signal of an input/output device 2 on an RS-232-C interface, is used as control signal to the input/output device 2. A transmission part 5 of a personal computer 1 executes the ON/OFF control by a program. At the time of OFF, a signal is communicated through an interface cable 8 to a receiving part 6 in the input/output device 2 and a control part 4 of the input/output device 2 is kept in the resetting condition through a resetting signal line 7. When the signal is changed from OFF to ON, a control part 4 is initialized, and thereafter, an operatable condition is obtained. Thus, without turning OfF/ON the power source of a personal computer system, the input/output device can be recovered from an abnormal condition.