I am attempting the same thing, and am following the design
at:

http://www.ccc.nottingham.ac.uk/~cczsteve/pic/pic84.pdf

  and a similar design at:
http://www.ebar.dtu.dk/~c888600/icsp.htm

The diode from MCLR to Vcc (through the MCLR pullup) limits the
voltage during programming when MCLR is 13v.

On some dev. boards, the header has been implemented as an RJ-45
connector.

>
> On Wed, 29 Apr 1998 11:07:49 CET, Marc Heuler <marc@AARGH.MAYN.DE> wrote:
>
> > I don't think this is a good idea. =20
>
> Right, hadn't considered that. Thanks.
>
> > Connect MCLR and RB6 and RB7 and GND to the ISP header.  Have all VDDs =
> at
> > 5V as normal in your circuit.  Tie each MCLR to its own PICs' VDD with =
> a
> > 5K1 resistor (as long as you don't have a power supply monitor chip in =
> your
> > circuit).
>
> Hmmm, is that going to be okay when the programmer pumps 13 volts through
> MCLR? I guess that's what the 5K resistor is for...
>
> Thanks for your input, I appreciate it.
>
> Later,
> Jon
>
> --------------------------------------------------------------
>    Jon Hylands      Jon@huv.com      http://www.huv.com/jon
>
>   Project: Micro Seeker (Micro Autonomous Underwater Vehicle)
>            http://www.huv.com
>


Jonathan Cline
jcline@vision.calpoly.edu