"When doing a CALL or GOTO instruction, the user must ensure that the page
select bits are programmed so that the desired program memory page is
addressed. If a return from a CALL instruction (or interrupt) is executed,
the entire 13-bit PC is popped off the stack."

Does this mean that the PCLATH <4,3> will still be set according to Page1
after the return, so that I need to clear the PCLATH register again after
the call returned from page 1(or rather before the nect call or goto
instruction)?

For example:

org    0x500    ;page 0
main
....
#page_1        ;macro{PCLATH <0,1>}
call    sub4
...
#page_0        ;macro{PCLATH <0,0>} ???
call    sub2
...

#page1
call    sub4        ;all in page 1
call    sub5
call    sub6
...
#page_0
goto    main
...
sub2
return
...
sub3
return

org    0x800    ;page 1
sub4
......
#page0
call    sub3
#page1    ;???
...
return

sub5
...
return

sub6
...
return
end


or should I just put a pagesel before each and every call or goto?
(I did not write the code for paging from the start)

What is the norm here?

Regards

Francois




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