During power-on for both TX simplex and RX simplex cores, the pma_init and reset_pb signals are expected to be High. INIT_CLK and GT_REFCLK are expected to be stable during the power-on sequence. Due to the auto simplex recovery feature, both boards can be brought up independently. If the RX board is brought up first then when the TX board is brought up, data transmission can start immediately. However, if the TX board is brought up first then no data transmission should take place until the RX board comes up based on the periodic CB pattern sent by TX.