Andy Stubbins wrote:
..........
>to overcome these issues. The problem is that the format for this procedure
seems to suggest (according to the MPASM user guide) that when you return
from the subroutine <label>, the PCLATH counter resets itself whilst
returning to the address stored in the stack. This is not the case
.........


Andy,

I have read the exact same words from Mchp, and had exactly the same
experience as you. Maybe someone else can decipher them better than me.
However, I have found that code along the following lines seems to work
reliably:

            call    zero                ; set zero state.
            bsf     PCLATH,     3       ; select page 1 for call.
            call    set_async           ; config serial port.
            call    auto_baud           ; autoset baud rate.
            bcf     PCLATH,     3       ; select page 0.
            call    signon

This is for PIC73/74, which have 2 code pages. The code shown resides
in page 0, the middle 2 routines are in page 1, the others in page 0.
All routines end with a simple < return > statement.

In other words, the appropriate PCLATH bit is manually adjusted
both *before* and *after* making calls to other pages.

I use the same format for making calls to page 0 from page 1, in
which case, of course, the bit set/clr would be reversed from
that shown here.

best regards,
- Dan Michaels
Oricom Technologies
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