Rx_SYS
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | Rx_SYS | Rx_BRK)) {
if (r1 & (Rx_SYS | Rx_BRK)) {
if (r1 & Rx_SYS)
up->tty_break = Rx_SYS;
(Rx_OVR | FRM_ERR | PAR_ERR | Rx_SYS | Rx_BRK))) {
if (status & (Rx_SYS | Rx_BRK)) {
if (status & Rx_SYS)
zport->tty_break = Rx_SYS;