Also move a couple more things under #ifdef DEBUG in an attempt to
reduce the code size for ATmega168.
It current doesn't fit in the '168 but maybe after some more tweaks.
Use unrolled loops to sample at 2MHz & 4MHz rates. Based on some
testing by Bob Davis (http://bobdavis321.blogspot.com)
The maximum with a 16MHz clock is 5.3333MHz (3 cycles per sample) but
sampling at that rate isn't very accurate. Accuracy is pretty good at
2MHz & 4MHz.
Triggers are more reliable on PORTB. I am working on fixing triggers
on PORTD, but I'm setting this back to original behavior (with a
#define USE_PORTD available) so this isn't broken for triggering.
The Arduino Mega 2560 is now supported in addition to the regular
Arduino. The Mega supports 8 channels and 7k samples. The ols.profile-*
files are device profiles for the alternative SUMP client. 'AGLA' =
Arduino 'AGLAM' = Arduino Mega
