You can use any of the four, typically #1 is used.
When you set up the TITO using the ekey 7 you specify what port you are using.
TITO IGT AVP Setup
Insert Ekey 7 with the machine powered on
Touch Setup
Touch Communication
Touch Protocol
Serial SAS 1 - Set Port to “COMM 1†or whatever comm port you are using.
Set Address to - “1â€
Touch Advanced
Under Protocol Enabled make sure it says “YESâ€
Touch SAVE and OK
Touch NEXT
Voucher IN/OUT, set for “Serial SAS 1â€
Touch Advanced
Validation Style, choose “SYSTEMâ€
Accept Vouchers, change to “YESâ€
Print Vouchers, change to “YESâ€
Touch SAVE and OK
Legacy Bonusing, touch once if need be
Make sure it is set for “Serial SAS 1â€
Touch SAVE, BACK
Touch EXIT
Remove Ekey 7
Cycle the power on the power switch