| 摘要 |
PURPOSE:To restore synchronism by means of manual control by detecting errors as for one-frame length of data respectively while shifting frame timings one by one bit to obtain correct frame position. CONSTITUTION:One-frame length of input data 1 is stored in a register 3, and an error detection circuit 4 detects errors from this stored data. The result of this detection is used by counters 5 in a number corresponding to the counting number of a frequency division circuit 8 that generates frame clock for the accumulative counter 5 to count the number of times of errors. The results of these countings are decided at every number of times determined by the frequency division circuit 9, and displayed on a display circuit 6. At the accumulative counters 5, only counters corresponding to time-positions segmented by a correct timing, become smaller than others. Therefore, by observing the LED display, how many bit a frame clock is shifted from inputs can be known. As a result, the synchronism can be restored when only the necessary number of bits are shifted in a necessary direction. |
