Hi Ben,

GP3 is the _MCLR/GP3 bit.  You have to do two things to disable _MCLR before
it will run with the simulator.

1.  Make sure you have a "__CONFIG" Statement.  ie:

 __CONFIG _CP_OFF & _IntRC_OSC & _MCLRE_OFF  & _WDT_OFF

Make sure it does not start in the first column and _MCLRE_OFF is specified.

2.  In MPLAB, go into:

Options -> Processor Setup -> Hardware

And then click off "MCLR Enable".

Good luck,

myke

>Hello,
>
>        I can't seem to get a stim file to work with a 12C509 in MPLAB
>6.31.  I have done this before on another machine without problems and
>now I don't see any changes in my I/O register.  Anyone have a
>suggestion?
>
>Thanks,
>
>Ben
>
>!
>! Serial Input @ 2400 bps Test
>! Bits are sent 0, 1, 2, 3, ...
>STEP    GP3
>1       1
>500     0
>917     1
>1333    1
>1750    0
>2167    1
>2583    0
>3000    1
>3417    0
>3833    0
>4250    1
>4667    0
>5083    1
>5500    0
>5917    0
>
>

"Programming and Customizing the PIC Microcontroller" is the January 1998
Electronics Book Club Main Selection.  See "http://www.myke.com".