[SOLVED] Running a JDM programmer off a laptop.

Is it correct that the reason you cannot use a JDM programmer off a laptop serial port because with this setup there is not a high enough voltage supplied to the MCLR pin on the PIC?

My laptop detects the programmer and the PIC (16F628A) OK, and it can read and save the program to file.

However, if I try to program the PIC I get errors.

Is that just because of this too low MCLR pin voltage?

I measured the voltage at the MCLR pin. It starts off at -0.11V. Then when I try to program the PIC it jumps around from say 5V to 10V (on my cheap DMM).

Should that voltage be a steady 13 V?

If so, I will try disconnecting the MCLR connection to the chip and connect an external 13V supply to the MCLR pin of the PIC whenever the MCLR connection from the programmer goes above 5 V.

Does anyone think that would fix it?

Thanks.

An insufficient level of programming voltage (Vpp) can certainly be an issue when programming.

However, I've never used a JDM programmer and therefore not familiar with its design to speculate further.

Have you considered obtain a PICkit or clone equivalent which utilize the USB port?

BigDog

Post #6 circuit in this thread:
https://www.edaboard.com/threads/263863/

JDM resting on a dusty shelf, why to wake him, he have bright moments in history, but now is 2012 year. You can use Pickit2 Clone to practice DIY or you can buy some good commercialized programmer. Usually Pickit2 Clone finish all home users programming jobs.

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Check what uC did you select PIC16F628 or PIC16F628A, they are not the same, programmer will show problem.

Yes yes yes. But you know that if you want to start experimenting without justifying the expense of a commercial programmer what can you do?

Even the clones are a lot of hassle especially if you know nothing about programming. You still have to program the chip somehow anyway. Where would I get that done without building a JDM programmer?

I built a JDM prgogrammer for $3. The WinPicPgm software works fine for the three PICs I have used so far. It does have settings for both PIC16F628 and the PIC16F628A. And most of my laptops have a serial port anyway.

The first thing anyone seems to say to any question about the JDM programmer is "Don't waste your time". But all the alternatives are way more complex and more expensive. In fact trying to connect anything to a usb port is a hassle for a absic hobbyist like me.

Maybe I should start a JDM PROGRAMMERS GROUP. :grin: Keep the spirit of basic electronics alive.

But anyway, thank you both. Tpetar, I appreciate your input on the posting at https://www.edaboard.com/threads/263863/#post1178766. The circuit you provided answered my question above and explained how these programmers work. But zsolt1 was saying "can I do this to get the JDM programmer working?" and your first comment was don't waste your time.

Cheers and merry christmas.

JohnJohn20 said:

But zsolt1 was saying "can I do this to get the JDM programmer working?" and your first comment was don't waste your time.

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Can you point where I say that?

My first comment in that thread was :

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.

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We assume, that people will try later to program some other uC, then some other, then some other. Electronics is not one project and one uC. I make one programmer for few uC, program that uC over weekend and I'm done in electronics, and all over. All advanced users pass through this, and they give intentioned advice.

You say you built your programmer for 3$, ok. Next time when you try to make some project and you realize that your programmer cant program that uC, because some error or device is unsupported, you will go to make some other programmer, its additional 3$ or who knows how much. PICKit 2 Clone can be done for under 10eur, even completed to buy.

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OK I stand corrected but your first comment gave me that impression. maybe I was being too thin skinned..


Tpetar. Sorry. Your Tesla quote gave me another thought.

Have you ever heard of people putting a big plate aerial in the air so that it captures static charges and charges a capacitor.

A friend gave me an article called Nikola Tesla’s Aerial System at https://www.free-energy-info.co.uk/Chapt7.html

I was going to just string up some aluminium foil and see what it caught. Any thoughts?

Best receiving of high amplitude voltage and high amount of energy, is if you put that foil on roof during storm.

Its radiant energy system.

Read about cosmic energy. Read about Tesla electric car Pierce Arrow.

tpetar said:

You say you built your programmer for 3$, ok. Next time when you try to make some project and you realize that your programmer cant program that uC, because some error or device is unsupported, you will go to make some other programmer, its additional 3$ or who knows how much. PICKit 2 Clone can be done for under 10eur, even completed to buy.

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Seems to me that you are saying don't waste your time.

I will call this as advice if you plan to work with uC in many others projects. If you have one project and need to program just one particular uC or few of them, and JDM support them, then make low cost JDM and finish a job.

You can do what you want, I dont want to convince you in something or something else. I just tell this, because we all pass through that process, and make some conclusions.