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[SOLVED] Check my JDM programmer for laptop com port

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Full Member level 6
Aug 11, 2012
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Cluj-Napoca, Romania
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i modified a little the popular jdm programmer, in order to make it work with a laptop com port.
I would like to ask some opinions about it, regarding it's functionality

Re: JDM for laptop com port

Better use FTD chip and run this programmer over USB port. Newer laptops dont have Serial ports, but you can get real RS232 even several ports over PCMCIAExpress cards, but you need to buy this expansion card.

Search EDABoard and look for JDM programmer posted by Fragrance.

JDM is old programmer next should be newer PICKit 2 for practice.


Re: JDM for laptop com port

Thanks, i know about other programers () but i stick to my idea, it's ment to be a weekend project .......
Hi zsolt1. I am glad someone is interested in using JDM programmers.

I would like to modify my existing JDM programmer to work off my laptop. I was thinking that it is just a matter of applying 13.7V to the MCLR pin of the PIC rather than relying on the Serial port to supply this.

Did you modify an existing JDM programmer circuit to make this?

If so, did you simply add an external 15V power supply (via a 270R resistor) or was it more complicated than that?

Thanking you.

Darn. I wish I had seen that before I built my programmer.

Ahhhh. So most of the original JDM programmer was just to provide the voltages for the MCLR and +ve power pins. The DATA and CLOCK pins can just be connected to the to the TTL serial port outputs.

So simple.

OK. So, apart from the fact that newer laptops don't have serial ports, are there any other good reasons to evolve to the USB type ones like PICKit 2.

PICKit 2 probably has better support but my programming software (WinPicPgm) seems to work well.

Thanks again.

OK. So, apart from the fact that newer laptops don't have serial ports, are there any other good reasons to evolve to the USB type ones like PICKit 2.

Point is not in USB/RS232 ports, any laptop/notebook can have LPT and RS232 even latest models, point is in programmer capabilities, what he can do, and what uC he can program.

Its like, that you prepare some oldtimer to race with some newer racing cars.

PICKit2 Device Supporting List:
PICkit 2 Device Support List_1298130726389.jpeg

i just added 13 V on 100u/16v cap from a external power supply. I use frequently PIC 16f628 ,16F84,,12f675 (...and c24 memory's when "pirate"ing Blaupunkt car radio's ;-) ) For more various PICs, i recommend a pick kit 2 clone.


to see more interesting projects check sometimes my web page (under construction) , to get there ... be clever and find that place ;-)


  • Modified JDM programer.pdf
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