The female header of the PICkit 2 accpets 0.025" square pins with a 0.100" spacing (2.54 mm). I usually use 5 pin 0.100" straight male headers on the target boards.
I'm always careful about connecting it properly the female connector of the PICkit 2 is non polarized, but Vpp is marked with a white triangle.
I thought I would have used cable with a Molex connector at its end and Molex headers on the boards, but I've never plugged the programmer wrongly up to now. Also, non polarized straight headers are really cheap, you can buy them in rows with 40 pins for 0.20 $
When you plug in a 2x5 ICSP backwards on a ICD2 clone (inchwrom) it does not dammage either the target or the ICD2. The ICD2 will ID the target PIC with 0xFF device code.
I can not swear by it, but I would guess that I have reversed the JuneBug ICSP connector as well.
I doubt that you can dammage the Pickit2 by reversing the ICSP connector. If that was the case the engineer should have used a polorized plug.
You need to look at the circuit that results from a backwards hookup to be sure.
This is especially true if you use the PICkit2 with a 6 pin header on the target board, in my opinion. The 6th pin of the programmer is not internally connected as far as I know from the manual and if you plug the programmer reversed, Vpp, that is the only voltage that *might* damage the PIC, is not applied to any pin.
As he said VPP is the only voltage that would damage the PIC and it will not be turned on if you have the plugin wrong.
When Pickit2 powers a target it measures the voltage. If the target is not plugged in right it will have a difficult time driving it to or near +5, Pickit will sense this and turn off the power to the target. I think I have that right
well the solution is simple I will put a 5 or 6 pin header on my boards and always plug in the pickit 2 so that the top is acing me when I am looking at the component side of the board
if you want to make it "imposible to be plugged in, reversed", probably some sort of connector would be required.
Here is one design from my group: **broken link removed**