Electronics DIY blog

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Monday, November 12, 2012

YAP2C - Yet Another Pickit 2 Clone

After a long break from the electronic scene, I've decided to pick up the drawing board again.

Since Microchip dropped support for ICD2 (Cypress based clone) all x64 Windows OS (since Vista at least) fail to recognize it.
The solution is to use it in an other machine with a x86 OS which is not practical, since that is not my main PC.

Pickit 2 (Microchip also is discontinuing) is a fine replacement for now for my needs. It is small.easy to build and is supported in Vista/7 x64.

So I decided to make yet another clone based on many other clones that are out there. Of course, also has many other clones out there, it is made of the most common electronic components found out there.

Pickit 2 has the following pros:
  • Microchip has open schematics and software for this programmer.
  • Small size form.
  • Easy to build.
  • Easily customizable.
  • Made of common parts and a single 18F2550 PIC
  • Can be integrated with several programming/compiling tools.
  • Doesn't need to download software each time you have to program a different part.
  • My simplified version can supply power to the target without penalty for the USB port.
  • It's a single side PCB with only a few shunts on the opposite layer.
Cons:
  • Does not support most recent PIC (not a big deal for me at this time).
  • My simplified version can supply power to the target without penalty for the USB port but requires external dc adapter.
  • My simplified version is for 5V parts only. (although it can be overcome with an adapter between the Pickit and the 3.3v target).
  • My simplified version has no leds (visual status of PIC).
  • My simplified version has no memory for standalone programming.
So here is the schematic and PCB:
Schematic

PCB

And here is a 3D simulation of the circuit. Some parts are missing (I don't have the model) and others are not exactly the specified format but it can provide a good idea. I'm considering changing the inductor to an axial type to save more board space and give it more room.

Pickit 2 - bottom

Pickit 2 - top
My only doubt right now is if I can reproduce this on CrappyCNC. But first I must fix it (yes I've done a stupid thing with it and broke the CNC...lol). Since it was build from root by be I'm not that concerned. The good thing of doing things your self is that you know how to rebuild/fix in case of an accident. ;-)

For more info on the way the Pickit 2 works check this link.

See you next time...