needed a 16 bit fine control in an experiment and I realized it with two potmeters, one for coarse and one for fine control

After some tweaking I got this more generic function

uint16_t analogR(uint8_t coarsePin, uint8_t finePin, uint8_t bits) // bits = bits per potmeter 1..8, so the result will be twice that nr of bits.

{

if (bits > 8) return 0;

uint8_t shift = 10-bits;

// analogRead(coarsePin); // opt. to remove noise by double read

uint16_t value = (analogRead(coarsePin) >> shift) << bits;

// analogRead(finePin);

return value & (analogRead(finePin) >> shift);

}

I restricted the number of bits per pot to 8 to minimize noise fluctuations.

thoughts for improvement:

* three pots? four?

* why restrict both pots to same # bits?

* how to do odd # bits? e.g. 15 bits so I could use the sign bit for errors.

just to share