UART_DM_IMR
uart_setreg(bas, UART_DM_IMR, 0);
uart_setreg(bas, UART_DM_IMR, u->ier);
SETREG(bas, UART_DM_IMR, u->ier);
SETREG(bas, UART_DM_IMR, u->ier);
SETREG(bas, UART_DM_IMR, u->ier);
SETREG(bas, UART_DM_IMR, u->ier);
SETREG(bas, UART_DM_IMR, u->ier);
SETREG(bas, UART_DM_IMR, 0);
SETREG(bas, UART_DM_IMR, u->ier);