I developed a list of different component, in Arduino or simple electronic and now I’m experiencing issues like “restart” or false signals along the signal cables.
For example, I’ve got a simple timer, it make a countdown and it is composed by a button, a 4 digits 7 segments display and a ATTiny85. I attach simple schematic view.
The “start” signal has a pull-up resistor and the timer restart when the signal goes down.
The “stop” signal has a pull-down resistor and the timer stop when the signal goes up.
Yesterday, the timer restarted autonomously, even if no-one made anything (no-one pressed the restart button). Cable that bring the signal down is, I think, 5cm long.
The power supply is built as following
- AC 220 to DC 12V - with a power supply 1A
- DC 12V to DC 5V - power regulator
We noted something similar with another tool where the cable is longer (quite 2m): a Raspberry Pi should send a high signal along the cable and when we have a current spike in the flat (we turn the light on or we turn on a drill or - it happen - when just we connected the drill to the plug), the cable bring a floating high value alone…
Could someone give me some ideas on out to fix this issues?