URE_PLA_RXFIFO_CTRL1
ure_write_2(sc, URE_PLA_RXFIFO_CTRL1, URE_MCU_TYPE_PLA, URE_RXFIFO_THR2_NORMAL);
ure_write_4(sc, URE_PLA_RXFIFO_CTRL1, URE_MCU_TYPE_PLA, rx_fifo1);