PDC_PTCR
DBGUREG(DBGU_PDC + PDC_PTCR) = PDC_PTCR_TXTDIS | PDC_PTCR_RXTDIS; \
PUTREG(sc, SPI_PDC_BASE + PDC_PTCR, PDC_PTCR_TXTDIS | PDC_PTCR_RXTDIS);
PUTREG(sc, SPI_PDC_BASE + PDC_PTCR, PDC_PTCR_TXTEN | PDC_PTCR_RXTEN);
at91usart_writereg(sc, US_PDC + PDC_PTCR, PDC_PTCR_TXTDIS | PDC_PTCR_RXTDIS);
at91usart_writereg(sc, US_PDC + PDC_PTCR, PDC_PTCR_TXTEN);
at91usart_writereg(sc, US_PDC + PDC_PTCR, PDC_PTCR_TXTDIS);
at91usart_writereg(sc, US_PDC + PDC_PTCR, PDC_PTCR_TXTDIS | PDC_PTCR_RXTDIS);
at91usart_writereg(sc, US_PDC + PDC_PTCR, PDC_PTCR_RXTEN);
at91usart_writereg(sc, US_PDC + PDC_PTCR, \
US_PDC + PDC_PTCR, PDC_PTCR_TXTEN);
US_PDC + PDC_PTCR, PDC_PTCR_TXTDIS);
US_PDC + PDC_PTCR, PDC_PTCR_TXTEN);
US_PDC + PDC_PTCR, PDC_PTCR_TXTDIS);