S+, PE I don't think it's rs485, if I remember right it's TTL because I had a max232 to interface a pc
I had the pc connected to S+ that used SAS legacy bonus to add credits by service/change switch.
I did not keep S+ connected that way long for some reason. This is from memory since I have not had a S+ for about 4-5 years.
I know S2000 has both both RS232 and RS485.
Also legacy bonus has been deprecated in newest SAS docs.
how SAS works:
The host polls the machine
If the machine has a SAS event to report it does so (door, ticket inserted, etc)
Only one event per poll and most if not all events are logged with time stamp by host
And they are prioritized by the machine i.e. A voucher or ticket event will occur before a door event for example
Then host processes the poll response i.e. Redeem a ticket, etc
I have an arduino as my SAS host. It also outputs messages to a vfd and input from a keypad
I can activate a preset legacy bonus by pressing the change / service player button twice (candle light on then off) or 1 to 5 key on the keypad. Giving me 5 preset bonus amounts. The 5 and toggling the change lamp are same amounts. It also handles TITO and displays various errors and other messages related to SAS events I monitor including TITO.