UARTCR2_TE
cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
cr2 |= UARTCR2_RIE | UARTCR2_RE | UARTCR2_TE;
cr2 &= ~(UARTCR2_TE | UARTCR2_RE |
writeb(old_cr2 & ~(UARTCR2_TE | UARTCR2_RE),
cr2 |= UARTCR2_TE | UARTCR2_RE;
cr &= UARTCR2_TE | UARTCR2_RE;
temp &= ~(UARTCR2_TE | UARTCR2_TIE | UARTCR2_TCIE);
writeb(UARTCR2_RE | UARTCR2_TE, port->membase + UARTCR2);