| 摘要 |
PURPOSE:To surely and accurately detect an error of an interrupted data signal by detecting the state of the data signal in a signal transmission line and detecting coincidence/dissidence of plural signals. CONSTITUTION:The presence of an error in a data signal is discriminated by utilizing that a normal data signal has a change point at one over an integer of its transmission speed. That is, when the data signal sent to a transmission line 2 is normal at present, a change point from 0 to 1 or from 1 to 0 takes place at every one over an integer of a transmission speed. The change point in this way is detected by a change point detection and coincidence detection section 1. On the other hand, since an oscillator 3 generates a frequency being one over an integer of its transmission speed, the change point of the both is made coincident while the data signal is normal by synchronizing each initial phase. The presence of an error in the data signal is always monitored digitally by discriminating the rate of occurrence of the coincidence/dissidence of the change point at a discrimination section 4. |
