Isolating PGD and PGC

[mynameisdan]

I had a quick scoot round the forums and google but I didn't have much luck, I'm wondering how I can isolate PGD and PGC from the rest of my circuit while programming. I was thinking to use 2 MOSFETs (because that's what I have) tied to MCLR. Looking on google I saw a schematic that uses 2 10K resistors. I thought a simple pull down would be enough but I have very little space left on my board and I'd like to get it right first time.

At the moment I simply unplug a connector that goes to a LCD while programming, but ideally I want to be able to leave everything connected.

 

[Wp100]

Hi,

Have a look at page 27 of the Microchip Pickit2 Users Guide which shows you how to connect Mclre / Vpp.
Clk and Dat if used on the output data lines d6 / d7 to the lcd will probably be ok with a 470R or 1k resistor in series as shown in the same diagram.

 

[mynameisdan]

Hi Wp100,

I have looked at the diagram and the resistor values are unmarked, I will try a 1K resistor in series. Thanks.

 

[be80be]

A 470 to 1K would work fine I would use a 1K or bigger if you can

 

[cobra1]

I always use 10k resistors to isolate the PGC, PGD lines

 

[mynameisdan]

Thanks everyone.