Bob Ammerman wrote:
> No. The program counter is always pointing at the _next_ instruction.
> Thus, adding zero to it is effectively a NOP.

Yes, but that's not what ADDWF PCL with 0 in W does on many PICs.  It adds 0
to the low byte of the program counter and copies the remaining high bits
from PCLATH (and PCLATU on some PICs).  That can be very different from
adding 0 to the whole PC, which can't be accessed directly on most PICs.

> NOTE: You must be careful not to span a page boundary ( a multiple of
> 0x100 instructions ) with the above construct because only the least
> significant byte of the program counter is affected by the ADDWF
> instruction.

Exactly.


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