thank you for your reply,,it means a lotHere is generic datasheet for the microcontroller chip used.
You'll need to trace the circuitry to find the two ADC pins, one for the voltage input and the other for an external current shunt, that'll come from a board connector to the chip. A good clean set of large hi-res photos of front & back of board will help to work it out.
There's work been done on replacing the MK1841D3 with an ATMEL "Arduino" chip for modding Hot Air Stations but they have one display and two measurement channels. Not sure if pinout is the same; best to trace through the board you have.
by Jake Hertz
by Jake Hertz
by Jake Hertz