A few days ago, I posted a message saying that  I had
attempted to use the fi directive in mpsim to shortcut the counting of
a counter and speed up the tracing process.  I used one file to set
the high byte of the counter and another one to reset the low byte.
mpsim appeared to be perfectly happy with what I told it to do, but
only one of the registers in the counter would get stuffed with the
value in the file called by fi .

        After some experimentation, I figured out that mpsim must
want you to use only one input file at a time.  If you open a second
file in mpsim.ini, for instance, it silently closes the first file and
opens this new one.

        Nothing is said about this in the documentation, but it is a
logical way for it to behave even if it wasn't what I expected.  The
main use for this command was to let one simulate the output  of the
A/D converter which it should do nicely.  Since nothing said one
couldn't do this, I expected that it would keep opening new input
files until either some limit in the mpsim executable was reached or
one exceeded the DOS open-files limit.  It turns out that the limit in
mpsim is 1 at any given time.

        This is not a gripe.  I couldn't do this project without mpsim
and I am glad that Microchip gives us mpasm and mpsim as well as mplab
for the Windows users.  I am just relating this discovery to save some
others the same confusion I had.

        Martin McCormick