I'm funding a pizzeria which will be run primarily by my cousin. I'm a software engineer and I'm considering writing my own POS software. I have a good handle on the software side of things: building the interface, database, etc. Yes, I know it is quite a lot of work.
At least we don't do delivery. Anyway, what isn't clear to me is exactly how to interface with the hardware. Does anyone here have experience with that?
I haven't purchased any hardware yet, so for the questions below we...
writing POS software, interfacing with hardware

I haven't purchased any hardware yet, so for the questions below we...
writing POS software, interfacing with hardware