I was trying made a gear indicator for my bike, with manually sensing the gear shift. But failed, cause my bike has no separate "neutral" wire, instead there is gear sensor in-built...!! But not gear-position indicator...!!

The in-built sensor gives different output voltage at every gear.

It sounds good that all I need is just an Pro-mini & OLED. But, facing problem with the voltage reading on Pro-mini.

When I checking with normal multimeter, the output voltage is very stable.

I tried with the simple voltage reading code. And added the voltages ranges as shows on multimeter.

Later Checked with Uno, Reading is quite stable (+- 0.02V).

But, Pro-mini voltage reading is too sensitive. Sometimes, in same gear position getting high voltage difference. So, in result I doesn't getting a stable voltage reading or gear display.

  1. Need suggestion to make changes, so the pro-mini also read like the multimeter / Uno reads. (Is this because of Pro-Mini doesn't have the Op-Amp in-built?)

  2. And, also, Why the serial output is around 1.5V, while no input in A0...?

PS: I didn't use voltage divider, because, gear sensor output voltage is below 5V.

  • 1
    That shouldn't happen. I assume it's a 5V 16Mhz Pro mini. Make sure power doesn't go through the voltage regulator on the Pro Mini. Try a different Pro Mini. Try a different analog pin on the Pro Mini. Try out the UNO again, to make sure the sensors signal still stable. You could try averaging the results to get a more stable value, but that's more something you'd do if the signal isn't very stable.
    – Gerben
    Oct 5 '20 at 15:27
  • 1
    Okay, now that's very quick... After searching & trying over weeks... Just changing the Analog pin works perfectly. (-_-) Feeling Dumb... Anyway, thank you very much...!!!
    – BLUE
    Oct 5 '20 at 16:39
  • Another Question, The output gives around 1.5V without any input... Should I use 10K pull-down... or subtract that in programming?
    – BLUE
    Oct 5 '20 at 17:33
  • 2
    as long as you get discrete values for each gear, i wouldn't try to rebalance the equation.
    – dandavis
    Oct 5 '20 at 18:37
  • Ok. It stable, for no input at analog pin... But when I add the sensor output to A1, its again unstable. I connected multimeter & arduino together, no issue with multimeter, but the Pro-mini reading is messed up...!!!!!!
    – BLUE
    Oct 6 '20 at 10:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.