Are there any standards for in PCB programming pads?
location on board?
supply pins required as pads?
Also, how are these details given to the PCB manufacturer?
What about flashing software, and how to use it, and what OS it requires?
Dec 30.2019, 17:39:53
Well, I'd recommend test points at least 30 mils o.d. (bare SMT pads, or vias / TH pads) and 60 mils spacing (center to center).
You can place them pretty much anywhere. It might be handy to arrange them in patterns. TAG-Connect is a good example; you can use the connector-of-nails to program it during development, or a bed-of-nails test fixture in production.
Often you'll see a row of pads which run to obvious locations (power, ground, microcontroller), either a serial or TWI or JTAG port, or something like that. For a production test fixture, there's no reason to arrange them that way, it's just fun.