I have the Adventech terminal which have 4 Serial port, and our application are using only 1 (ttyS0) port for communicate the POS printer.
But few days the printer has not able to communicated the (ttyS0) port, we checked the printer with other terminal its working.
So now we need to remap the serial port and (ttyS1) should work as (ttyS0) so printer we communicated.