Brigadoon - An Occasional Corner on the Internet
Arduino Based Weather Station
Designed by Mark Little
Geiger Counter Monitoring
Although any Geiger Counter that provides an open-collector output, this project uses the Geiger Counter kit provided by Oatley Electronics. The output is set to be an open collector transistor that can be used to trigger an Arduino Interrupt. This is possible because an internal pull-up is set to ensure that the pin is normally HIGH and a pulse will pull the pin LOW, triggering the interrupt.
Connecting the Rain Gauge and Geiger Counter
In case of the tipping bucket rain gauge and the radiation monitor, only two wires are required to connect each sensor to the Arduino.
The two pins used were selected because those pins have a primary purpose of servicing external interrupts. The pins are configured to trigger and interrupt when the pin goes from HIGH to LOW.