Homebrew Microchip ICD2 Clone

rando · 03-02-2005, 03:37 PM

I've been asked about this since I mentioned it in another thread. There are several good PIC programmer circuits that can be constructed for < $10 on the web. The big limitation of most of them is the software. Unless the software that controls your programmer supports the PIC you want, you'll be out of luck.

The best way around this is to build a programmer that emulates one of the Microchip designs supported by Microchip's MPLAB development environment. This particular example goes one step further and emulates the Microchip In Circuit Debugger 2. It can program and debug any chip supported by MPLAB. MPLAB almost always has support for newer chips long before anything else.

The circuit I built is more or less exactly the one specified by Lothar Stolz (http://stolz.de.be/icd/main.html) I only changed the transistors to parts I had lying around. You can get all of the parts you need cheaply from Randy at glitchbuster.com or use Digikey, Mouser, Jameco, ... if you want to pay a bit more. The circuit board you can get at radio shack -- or maybe glitchbusters has them too, dunno. I think I spent less than $30 on this.

rando · 03-02-2005, 03:39 PM

My assembled board -- ugly!

rando · 03-02-2005, 03:40 PM

and the backside solder traces

rando · 03-02-2005, 03:43 PM

If you want to make it cleaner, download the free version of Eagle Schematic/Layout editor and build yourself a nice board. Then order a custom PCB from SparkFun Electronics for only $2.50 per square inch.

http://www.cadsoftusa.com/
http://www.sparkfun.com/shop/index.p...190157&cat=86&

jcdillin · 03-02-2005, 03:44 PM

ICD is awesome, so much cheaper than the incircuit I built with the huge relay. Great info rando.

Zac · 03-03-2005, 09:35 PM

Haha kickass thread dude. I built one on a breadboard but I think I messed something up.

Mplab connects, gives a few errors, says "ICD2 Ready" then nothing. Guess I'll try looking at the schematic once more.

Ah - also noticed you put the LEDs in...nice touch.

rando · 03-03-2005, 09:47 PM

I added 2 LEDs based on a different schematic that showed which pins they go on. I've only ever seen one of them light up though.

Sorry it's not working for you. Try debugging it a piece at time -- starting with your max232. You can completely ignore the target interface until you get the MPLAB communication part working with your PIC. Did you use the 16F876 or did you try the 876A or 877 or 877A? The MPLAB bootloader is for the 876 only I believe.

Zac · 03-03-2005, 10:36 PM

Yeah I'm using the 16F877 and it is probally why. I couldn't source a 16F876(non-A for some reason.) I burned the fw to it fine and the website doesn't mention any differences. What I think I'm going to do is just use a different schematic. I found ICD2_clone_3_4.zip (http://icd2clone.narod.ru/) using the 876A and the zip includes the bootloader. So I figure I can try that next....minus the whole SMD thing...

rando · 03-03-2005, 10:46 PM

You can get the 876 at glitchbusters.com. Check out the thread below. There is a link to ICD661.hex bootloader that supposedly will work with an 876A chip. Also a guy in there had problems making the circuit work with an 877 -- just like you.

http://www.picbasic.org/forum/showth...highlight=ICD2

Chris31 · 03-14-2005, 02:54 PM

Heres the PCB I made.

Added a power LED, polarity protection diode, smooting capacitor and a resistor to limit the VPP current just in case of a short. I believed rando blew one of the transistor