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Topic: DIY PicKit2 clone (Read 14269 times) previous topic - next topic

DIY PicKit2 clone

I recently built a BPv4 from parts and need to flash the bootloader.  Unfortunately I only have a JDM2 currently.  I do have a handful of PICs laying around, such at PIC18F4550 (code compatible with the PIC18F2550).  Can anyone recommend a simple circuit I could build on a breadboard using common parts.  I really only need it to last long enough to flash the BPv4 so simple is best here and I'd prefer to avoid having to order any odd parts.  As noted, I do have a JDM2, so I can flash code to the PIC18F4550 as needed.  Does anyone have a suggestion on a simple design for this?  I'm not necessarily stuck on the PikKit design and would be happy with any ICSP that is simple and has readily available software that can flash a PIC24FJ256GB106.

Re: DIY breadboard PicKit2 or similar

Reply #1
I moved it to the project development as I think it get overthere the attention it needs

Re: DIY breadboard PicKit2 or similar

Reply #2
Awesome, thanks!  I wasn't sure if it made sense in 'projects' or 'tools of the trade' since it's both...  more a project to built the tool I suppose.  :)

Re: DIY breadboard PicKit2 or similar

Reply #3
I believe I've settled on a design for this.  The schematic is shown here in pdf format:
This uses all through-hole parts and resuces the original PicKit2 complexity be eliminating the EEPROMs used for the ToGo programming (which I don't need).  I had planned to do this on breadboard, but I've decided instead to make it more permanent.  I want to take a retro approach on this so I'll be building it on perf board using wire wrap for the connections.

Does anyone have any suggested modification to this setup?

Re: DIY breadboard PicKit2 or similar

Reply #4
Hi drjeseuss,

I like to recommend PicKit2 lite version from Blueroomelectronics. I use this for long time without any problem.
Blueroom website is down now. Here is a backup copy link. It is more simplified and you can omit Opamp also.

And here is a modified version of Felixls and Suky for 3.3V targets. ... 5V3.3V.pdf

DIY PicKit2 or similar

Reply #5
Thanks for the recommendations.  I saw the design for micros-designs and almost went with it, but decided on the version I posted above.  Originally I was going to breadboard a one-shot programmer, but decided to go with perf-board and wire-wrap for something a bit more permanent.  As such, Ilike the design I chose as it retains most of the original PK2 features, including IDE adjustable voltages instead of fixed voltage, as most others have.  Also, I'll be adding a header to allow me to add a module for the EEPROM down the road if I decide to use the ToGo programming function.  Having the memory on a seperate module will also allow me to tinker with it using my BP, or to pop into other projects.  I'll try to keep this thread updated as I go along on this build.

Re: DIY PicKit2 or similar

Reply #6
Hi drjeseuss,

Yes, if you stick with original Pickit2 plan and autovoltage detection feature, your design seem the best. Consider changing Opamp and FET with widely available parts.
I believe that 2N2700 FET can be replaced with normal transistors such as 2N3904, C945, BC547, BC557 (in my construction, I used C945 and BC557 without any problem).
For Opamp, MCP601 cannot be found in my place. I need to check lowpower, single supply, rail to rail opam replacement or is this possible to use normal common Opamp.
Anyway, I also to interest auto-voltage detection feature to add my existing Piclit2 lite.

Re: DIY PicKit2 or similar

Reply #7
I got the parts this past Friday for my PicKit2 Clone build.  I spent $8.20 on Mouser for the parts.  A few things like the USB cable and header were used from my part bin.  I could have saved more if I would have dug out resistors and caps from my bin also, but was in a hurry when I placed the order and wanted to be sure I had all I needed for this build.  After the first two connections, I decided to abandon the idea to do this in wire-wrap.  I forgot how slow that process can be.  I decided instead to 'dead bug' the parts on the perfboard.  It looks terrible, but it works.  Most of the jumps were component legs insulated with heat shrink, but a few of the longer runs use actial insulated wire.

  After completing the build, I programmed the PIC18F2550 with the PicKit2 firmware using a JDM pin wiggler.  I connected to the PicKit2 Clone using both the MPLab IDE, and the dedicated PicKit2 application.  Both connected to the unit properly.  I loaded up the bootloader hex for the BPv4.0c.  I then connected the PK2 to my BPv4.0c through the ICSP header and programmed the bootloader.  It worked on the first try! Success!

Overall, while very messy, this was an easy build and adds another multifunctional piece of kit to my toolbox.  Well worth the time spent on this.  If I had to do it all over though, I would choose to etch a board for this as the 'dead bug' approach got a bit crazy toward the end with wires going everywhere.  It became challenging to keep track of what connections were in place and what needed jumpers, etc.

Here's a link to my BPv4.0c build from a few weeks ago.

Top view of the completed board.

Bottom 'dead bug' side.

The PK2 connected and programming the BPv4