David Thompson wrote:
>
> Hi guys,
>
> My program is rapidly approaching the 1k mark and there is still a lot of
> code to write. The development system uses a 16F877, but the final design
> will probably use a smaller PIC - maybe a 16C73.
>
> The question is, are there any things to look out for when crossing page
> boundaries (2k with these chips, I think), or more particularly, are there
> any tricks to lessen the hassle of doing so?
>
> I've seen macros to do "long calls" and that kind of thing, which is why I
> am asking.
>
> Thanks,
>
> Dave.

The GOTO and CALL instructions can be used in any 2K bank of ROM space.

PCLATH bits 4 and 3 are always concatenated onto these instructions.
That gives four 2K banks to select from.

PCLATH  4  3

        0  0     0h -  7FFh  2K
        0  1   800h -  FFFh  4K
        1  0  1000h - 17FFh  6K
        1  1  1800h - 1FFFh  8K

Just check to resulting *.lst file if you suspect one of these
instructions jumped a page boundary.

--
Best regards

Tony

http://www.picnpoke.com
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