The MSBD-102-1 module is intended for use with the MWSR-100A overhead. It has two basic functions. First, incoming bursts of RS-422 clock and data can be captured into a 4K-Word FIFO for insertion into the overhead’s PCM stream. Each burst can be at a rate of up to 20 Mbps. In synchronous mode, the FIFO is reset and the data capture begins with the start of the first burst after a major frame. In asynchronous mode, the entire burst of data is captured before being available for insertion into the overhead’s PCM stream.