I installed 65 cash registers all over Ireland. Each one had only an RS232 serial port. I had to read and aggregate their daily reads between 5am and 10am (only time these outlets were not running).
It was not possible to read this particular cash register when it was in operation mode OR if it was in OFF mode. Also we did not have access to GSM sims and there was no WIFI at stores.
SO:
We installed 56K modems and plugged them into the regular PSTN lines.
BUT:
That would interfere with customers calling to order out.
SO:
We plugged them into analog plug timers and only had the modems switch on between 5AM and 10Am.
AND:
The store owners kept switching Off the tills. So we had to disable the off position for all the tills.
The backend was a VB6 app running a 56K modem that read each till in turn and then processed all the results.
It was not possible to read this particular cash register when it was in operation mode OR if it was in OFF mode. Also we did not have access to GSM sims and there was no WIFI at stores.
SO:
We installed 56K modems and plugged them into the regular PSTN lines.
BUT:
That would interfere with customers calling to order out.
SO:
We plugged them into analog plug timers and only had the modems switch on between 5AM and 10Am.
AND:
The store owners kept switching Off the tills. So we had to disable the off position for all the tills.
The backend was a VB6 app running a 56K modem that read each till in turn and then processed all the results.
Ran for 11 years with not much bother.