LCD Keypad Shield – Entering and Storing Numbers

Projects Programming
20

WagnerJ:
2 short cables routed through bread board, but it does cross the RFID's serial1 cable, and the RTC's I2C cables

Thanks for all your trouble, at least I know where to look for the problem now.

If there is too much fluctuation and noise in the A0 ADC measurements, you could increase the tolerance for button detection, like perhaps:

  if (abs(adc_key_in1-adc_key_in)>3) return btnNONE; // if ADC reading is not stable, return btnNONE

But the more tolerance is allowed in consecutive measurements, the higher the risk for detection of a wrong button pressed.