This project uses a particle photon and m8n GPS receiver to output a speedometer pwm signal. The calibration is performed over wifi particle functions and is saved in the emulated eeprom. Can operate up to 18hz. https://www.hackster.io/macsboost/gps-r-a-photon-gsx-r-golf-cart-gps-speedometer-adapter-23e71d
I’d be nice if you could say a couple of words about the project, rather than just linking through. Gives people an idea of whether or not they’re interested.