I have an application which uses a PIC 16C58A. After a few years of
production, our customer would like us to make a small change in the
operation of the device. Unfortunetly whoever my job predecessor was did
not document any of the code, or it got lost. Anyway, I am stuck with
trying to either recreate the application code from scratch or reading the
code from the present device and dis-assembling it.

I am able to read the code out of the device using a PICStart Plus and
MPLAB. The code looks ok, but of course I don't have any of the meaningfull
labels. Not a big deal since I can walk thru it and add my own labels and
comments. HOWEVER
I found some lines of code which don't make any sense. I got one line
                TRIS    PORTC
The 16C58A does not have a PORTC, so how come I got a TRIS for that port?

Anyone have any hints for disassembling code from the hex file? Thanks.
Mark Walter