The button states could easily be read by using an Arduino’s analog input. A Pro Mini model was chosen for its small size as it could be housed in the radio compartment of the dash.

An Arduino Pro Micro provides a USB interface to a PC and reads out the various input units. The entire design is modular, so it can be customized to any desired combination of analog and digital ...

Then you will find a some how strange detail: a variable capacitor that can be optionally connected to an analog input of the Arduino. This part of the circuit is not directly involved with the logic ...

It is equipped with 32 Inputs (16 x digital 4-30V, 8 x analog 0-10V, 4 x analog 0-5V, 4 x analog 4-20mA) and 20 Outputs (8 x relay 250V/5A, 2 x open-collector 30V/1A, 8 x analog 0-10V) and offers ...