Make some commands, that have no interesting status, return "nothing"
(other than possible error).
Normalise adc return value to 16 bits
Cosmetics
Include number of ports in identify command, remove
"extended" commands.
Keep code as small as possible.
Avrdude less verbose
Rework commands (see features).
Major code overhaul.
Change includes to make eclipse happy (partial...)
Change interrupt vector + sei to interrupt(, NOBLOCK)
Add USB flow control.
Revision 6.
Make HVPP default.
Replace indexes by pointers to squeeze out the last few bits.
Extract low-level functionality and put it in new source file (phy.c).