Can someone please help me with what feels like a "floating" error. I've made a scoreboard and on occasion, the score climbs on it's own.
The board is made up of 15 LED seven segment common anode displays, powered with a 24V DC supply, control board (with shift registers and an Arduino Uno), and a 12V DC twelve channel remote.
The remote control receiver is made up of 12 relays. All commons are connected to ground. When I press the remote button, this connects the ground of that relay to an arduino digital pin 2, 3, 4, 5, 6, 7, or 8.
In my code I've defined these pins as input pullup:
The code is written so that false triggering can't happen - definately marks when the button is pressed, released and duration of press).
Between the digital pins and the remote relays, my connection was with 4 dupont wires (as I didn't have ones long enough). I changed these and "I think" it fixed the problem. However I'm not sure why. I thought pullup pins would stay high (+5V) unless definately grounded.
Any ideas anyone? I can't afford to have the score change on its own during a game