SLIP DETECTION CIRCUIT FOR ELASTIC STORAGE DEVICE

PURPOSE:To prevent the effect of fluctuation in a fault detection point due to jitter or the like by detecting a slip fault with a signal resulting from a write and read valid/invalid designation signal latched based on a reference clock signal. CONSTITUTION:Data are written or read alternately for each frame to two planes of elastic storage device 31. A latch circuit 32 latches a read valid/invalid designation signal RI of the elastic storage device 31 by using,e.g. a reference clock CK with 8kHz. An AND circuit 33 provides an output of a signal representing a slip fault area in which the read valid/invalid designation signal RI of the elastic storage device 31 and a write valid/invalid designation signal WI of the elastic storage device 31 are overlapped timewise with each other. A slip detection signal generating circuit 34 latches a write frame pulse WFP when an output of the AND circuit 33 represents a slip fault area to provide an output of a slip detection signal. In this case, a write control circuit writes two frames of data to the elastic storage device 31 consecutively.