Arduino MAX7219 Matrix Wiring
SimHub only handle one matrix, just enable the matrix in the sketch,
The matrix will show the current engaged gear.
If you use multiple devices with one matrix per arduino, the display will be replicated
Upload and follow the pin out suggested (GND, goes to arduino gnd, and 5v to 5V)
Then choose which font to use into simhub (the fonts can be customized into the MatrixFonts folder), not all the fonts handle more than 9 speeds (the font SQUARE-LARGE8x8 handle it)
Configuration can be accessed from the Arduino's Display and alerts menu
