#define DATA_PIN 11 //Green wire from AM-2640's power connector
#define CLOCK_PIN 13 //Blue wire from AM-2640's power connector
Check these; it might define the name with the number plus the comment. So
CLOCK_PIN gets replaced with "
13 //Blue wire from AM-2640's power connector". Do a printf of
CLOCK_PIN to check.
Edit: Hmm, the
#define on the arduino website seems to allow it, just don't use the end semicolon.