Going back to the original question, and assuming it's about the sort of low voltage circuits you'd interface to a Pi or Pico:
The ground wire serves two purposes:
The ground wire serves two purposes:
- Completes the circuit. No ground means no return path for the current. An LED with a connection only to its +ve pin won't light.
- Provides a common level for 0 volts. Without that it's uncertain that a high on one board will be seen as a high on the other.
Statistics: Posted by thagrol — Thu Mar 21, 2024 12:52 am