Elegant "in circuit programming"

[Ted's]

Why? However, if you are suggesting using the above components (that's a pretty authoratative statement), maybe you know something we don't, so share with us...

@bcd and @Melanie: My idea is to connect the bases of a series of transistors (or gates of a series of mosfets for that matter) via resistors to vdd of each circuit that should be separated. So a set of 5 items is necessary for each circuitry. So as soon as voltage is applied the right connection is open. I asked myself whether it is better to use a whole chip (which name?) or a series of transistors or mosfets or even opto-couplers. Whereas I do not know whether programming of a pic is partly analogue so opto-couplers might not work.

it's all been discussed before...

This is exactly what I presume. Every mp3-player must contain a similar circuitry - basically every plug and play device.

http://www.picbasic.co.uk/forum/showthread.php?t=516

That does not deal with the issues occurring when the pins needed for programming are used in the circuitry serving the pic aswell.

People give you suggestions here, things they use, things that work for them. You can do what works for them, you can take the idea and create something of your own, or you are free to do something completely different. But hey, let's not post a detailed specification and shoot people down when they don't meet it exactly!

Melanie, I am sure you want me to treat you with respect. If so, don't give me advice if not asked for it in general.

I let the water cool , ... then go back to the previous problem.

Nice. I like it because in some situations it is the right approach and in others...