Independently select the master transmitter and receiver channels from among all enabled transceiver channels. Enabled channels are identified by their coordinates on the transceiver channel grid. In the generated core instance, the TX master channel drives the source clock input of the transmitter user clocking network helper block, and the RX master channel drives the source clock input of the receiver user clocking network helper block. The TX and RX master channel designations are also used to configure the buffer bypass master lane when the transmitter buffer or receiver elastic buffer is bypassed, respectively.