|The gotcha is that a "harmless" in-page GOTO from the last address in a
|page results in an unintended page jump to the next page. See below. This
|is probably endemic to the entire 17C series, and perhaps all the
|multi-page PICs in general. I've tested it only on the '756, though.

The gotcha's that got me when I used the 17C756 were:

[1] That incf/decf affect carry (I ended up using incfsz/decfsz
    instead, even though I once had to add a nop afterward.

[2] That GOTO's affect PCLATH; on the 16Cxx family, a GOTO will
    ignore the lower bits of PCLATH but not affect them.  Since
    the current PC-Hi is never considered in address computations,
    the odd page-crossing behavior you described is not an issue.

[3] Of MOVFP and MOVPF instructions, one affects flags and the other
    does not.  Although it's generally possible to replace

                movf    A,w     ; 16Cxx instruction

    with

         movfp A,WREG

    The latter instruction does not affect flags as would the 16Cxx's
    "movf" instruction.  Does anyone know of a good 1-instruction equi-
    valent to "movf" that works over the entire address range?

All of these behaviors are documented, but they are different from
the way the 16Cxx behaves; anyone who's used to the 16Cxx chips should
be very careful when writing 17Cxx code to avoid these and similar mis-
takes.


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