Change credit value on Daverob dongle

[daverob]

Drunkenclam is correct. The external input of the dongle can only be set to award a number of credits per pulse (coin), and not a number of coins per credit. It would be possible to add this as an additional feature, but it's never been requested before (until now!).

I'm intending to make some changes to the parts of the firmware that read the external inputs (making it an interrupt driven background task, rather than 'polling' the input in the main execution loop). So it's possible that it would be a simple change to add this as a new feature. But my rate of progress with software updates is very slow at the moment, so don't expect this any time soon.