ASC_RXBUF_DUMMY_BE
c |= ASC_RXBUF_DUMMY_BE;
if (c & ASC_RXBUF_DUMMY_BE)
ascport->port.read_status_mask |= ASC_RXBUF_DUMMY_BE;
ascport->port.ignore_status_mask |= ASC_RXBUF_DUMMY_BE;