For error finding or debugging the Open Source Cart Reader can be set to output to the Arduino Serial Monitor instead of the LCD screen.

To enable the Serial Monitor change Cart_Reader.ino like this(same setting for all hardware versions):

//******************************************
// !!! CHOOSE HARDWARE VERSION !!!
//******************************************
// Remove // in front of the line with your hardware version    
// #define HW5   
// #define HW4   
// #define HW3   
// #define HW2   
// #define HW1   
#define SERIAL_MONITOR

Then upload and start the Serial Monitor like so:

Once launched you need to set it to no line ending and 9600 baud.

The Cart Reader is now controlled by sending keyboard inputs over serial. The files still get dumped to the SD card though.
If it says Press Button you can send any button. To select a menu entry you just send the number in front of the entry.

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