I just got my first Arduino board so I am new at this.
I have a Garmin 15xH-W OEM GPS receiver requiring 8Vdc to 40Vdc unregulated which I want to connect to Arduino Uno. I want to use 3 wires from the GPS, Red for Volts, Black for Gnd and Gray for the one second pulse. Uno only gives me 5V, so if I connect the Garmin to a 12Vdc supply, how do I connect Gnd to common for the GPS and the Uno?
With the power solved? how do I capture the pulse per second? Set a digital pin to output and read in a loop? I was not able to try this since I do not have a pulse yet.
The purpose is to count the 1 second pulses and then once every minute execute a new routine which will energize a relay and some more code after that. The relay requires 12Vdc to energize, so the same Common Gnd problem?
Your help will be appreciated very much.