22.2.4.3 Control Data Client (CDS)

The CDS bit is the first bit after the Start bit and “0” is always the state transmitted by the host. This bit is used by clients for ID confirmation and replies to host control data. This bit can be "1" or "0" when transmitted by the client. The eventual combination from each cycle’s CDS bits creates an entire control communication packet. Please see the Register Communication section for more information.