Bc2000 (for the BCF2000 & BCR2000)

> This is more or less typical 2's complement behavior.
> Since the BCR basically can't "think in negative values", I can't see a way to get rid of the jump.

OK, we'll have to live with it.  I'll note it in the comments.

> Any luck with "00 00 - 7F 7F"?

Actually yes.  I had to scroll all the way up to 241 to register a -15, but 241-271 does yield the full -15 to +15 range in numerical order.  (Actually it repeats periodically after that, every few hundred numbers.)  Can we limit the variable values to 241-271?

Otherwise done.