Rain gauges are typically tipping or see-saw based, providing a digital trigger at a rain threshold.
Tipping rain gauges usually provide a short digital pulse as the rain gauge tips. The input can be thought of as: off, tip (on briefly), off.
See-saw rain gauges change state with each tip: The input can be thought of as: off, tip (on, until next tip), tip (off, until next tip), etc.
The Flexi1's digital inputs are used. These are exposed through screw terminals:
- GND: ground input
- DIGITAL IN 3/2/1: options for digital inputs. Choose 1 per rain gauge.
Both tipping and see-saw setups should "pull to ground" when on. This requires the Flexi1's digital inputs to be set to pull up internally. This is configured in the OEM System Parameters:
- Bias resistor: Pull-up
- Active Level: Low (triggers when pulled to ground)
- Config1: this is the debounce period. It should be set low to ensure tips are captured. 100ms is a good option.
Note that the default Bias Resistor setting is Pull-down. This should be used when nothing is connected to the digital inputs. The Flexi1 uses slightly more power when idle and pulling-up on the digital inputs.