Is the HoneyPi and measuring mode or in maintenance mode? An LED light integrated in the housing can provide information about this. The light will be on as long as maintenance mode is active.
An LED can be connected to the GPIO21 (PIN 40). Once the maintenance mode is active, the GPIO21 will have approximately 3.3V.
The Raspberry Pi has already installed a very small light emitting diode. Therefore this additional LED is not absolutely necessary. However, it can be helpful if you want to give your housing this additional status indicator.
The pre-installed green LED on the Raspberry Pi indicates the following even without an additional LED:
- RPi Zero W:
- lights up in measuring mode, does not light up in maintenance mode, flashes during start-up
- RPi 3B:
- lights up in maintenance mode, does not light up during measurements, flashes when power is switched on until all services have started correctly
- Pin 40/GPIO21
- Pin 30/GND
- For the other sensors see wiring diagram and sensors.
Required components for this extension:
Translated 11.08.2019 by JK