Ok, so I am learning how to write code for the wiring and arduino boards, and I have a sid module laying around. I want to interface with it like TK's amazing PIC does, but first I have to know how the shift registers are written to. What is the process that the CORE writes to the SID module? Also, what is this MU, and SO connection for? I'd just go for a parallel interface but the sid won't stay on my breadboard, it pops out, and anyway, the module is nice and clean :-p