| 摘要 |
PURPOSE:To make it possible to a set a frame pattern detecting circuit that conforms to inputted digital primary group signal automatically by setting a means that inputs digital primary group signals and detects a frame pattern that detected a frame pattern as a frame pattern detecting circuit. CONSTITUTION:The system is provided with frame pattern detecting means 1-n for all kinds of DSI signals. A frame pattern detecting means 1 is selected first by a selector 3 according to a selection signal from a format selector 4. For instance, if a frame pattern is not detected, next frame pattern detecting means 2 is selected by the selector 3 according to a selection signal from the format selector 4 basing on outputted step-out signal. When the pattern is detected, the step-out signal is not sent out, and accordingly, the frame pattern detecting means 2 is set as it is as a frame pattern detecting circuit. Thus, time can be saved, and even when the frame pattern is changed, switching can be made immediately. |
