After much investigation, here's how I think I want to proceed:
- Arduino Pro mini 3.3v
- Solder on header 6-pin male/male (TLL side will need to remain exposed for external connection while in case)
- TLL converter to USB for comms/charging from PC
- Will need for functionality - install onto board
- BLE (RYB080 or equivalent) 3.3v module - this one I'm having a hard time finding in Canada so would love some thoughts on an appropriate equivalent
- Lithium Polymer battery (3.6vnom, 4.2vmax) - anything from an RC heli or car.
- Charging board (TP56 or equivalent)
I will design/3D print a case for this