I finally decided to try my hand at circuitry so I got a JDM programmer off ebay. I have been able to program a 12c508A SM chip with it (by soldering wires onto the pins and placing those into the programmer) but I'm having a helluva time trying to program 12f629s and 12f675s. In IC-Prog I get the infamous error about address 0000h. It actually writes the first 2 bytes fine despite what the error message says. I have tried changing every option that I can think of and even installed userport.sys and I still can't program them. In other programs I also get error messages after it verifies the write -- except they can't write the first 2 bytes. I also should mention that they can cleared no problem. I am using XP Pro and haven't had the chance to test 98SE on this desktop yet. I have however tried the JDM on 2 other XP desktops and a 98SE desktop (two of which are older Dells which I thought might have more power through the serial ports if low voltage was the problem). The manual for the programmer is located @ http://min.midco.net/crackerx30/MDJDM01USERGUIDE.pdf . TIA for any help anyone can provide.

 

There is an apparent problem with the JDM programming when it comes to programming these parts. I found a discussion of the modification that can remedy the problem here.

Maybe you can benefit from checking into this issue.

hgmjr

 

You may want to look into this programmer as a replacement for the one you have rather than attempt to modify it. At $14 plus shipping it seems to handle a number of devices including the 2 devices that you are having difficulty programming with your present JDM programmer.

hgmjr

 

Thanks for the info. I will admit that I'm pretty new to the electrical aspect of this so it's hard for me to decipher schematics. I can do the hands on work no problem though. Would you be able to take a look at the pictures of the programmer here and here. I'm hoping the front will be clear enough to see the traces. I'd like to try to salvage this programmer if I could. Ironically I passed up that same programmer you posted because I thought it might not be able to handle the chips I wanted to program and also because it wasn't ZIF.

 

Thanks for the info. I will admit that I'm pretty new to the electrical aspect of this so it's hard for me to decipher schematics. I can do the hands on work no problem though. Would you be able to take a look at the pictures of the programmer here and here. I'm hoping the front will be clear enough to see the traces. I'd like to try to salvage this programmer if I could. Ironically I passed up that same programmer you posted because I thought it might not be able to handle the chips I wanted to program and also because it wasn't ZIF.

I or one of the other members would be glad to provide you with suggestions.

I don't seem to be able to get the two links you provided above to do anything.

hgmjr

 

Hmm that's strange that you weren't able to view the pictures. Here they are embedded:

 

The board you have appears to be a bit different from the one that is contained in the website that I linked you to. They are very similar in design but your board seems to have a few more bells and whistles on it. For example your board has what appears to be a couple of LEDs on it. The schematic in the link I sent you has no LEDs on it. Your board has the 6-pin header so that you can use it to program PICs in-circuit.

Before we go making any mods to your board, let me do a little investigating around on the Internet to see if I can find modifications specific to your board and get back to you.

hgmjr

 

Thanks very much. I really appreciate you going out of your way to help me.

 

Greetings Cracker,

I was wondering if you received a schematic of the JDM programmer you are using. If so could you scan it and post it here?

hgmjr

 

Unfortunately, I didn't. It seems that MDfly (the ebay shop I got it from) has their own version of the JDM. :/

 

Unfortunately, I didn't. It seems that MDfly (the ebay shop I got it from) has their own version of the JDM. :/

I visited the ebay website and looked at the info on your porgrammer. It clearly lists the 12F629 and 12F675 as devices the porgrammer can handle.

Have you thought about contacting the seller and asking them if they have had any reports of programming problems with the 12F629 and 12F675? They may be able to provide you with information on what you need to do to accomplish the programming.

hgmjr

 

I actually had done that previously and they just referred me to WinPic. My subsequent email was never replied to.

 

I actually had done that previously and they just referred me to WinPic. My subsequent email was never replied to.

Did you download Winpic and see if it would resolve your programming problem?

hgmjr

 

Yeah I've tried WinPic, WinPic800 (not sure what the difference is), PicProg4U, and some other rare programming software that I found during searching in addition to ICProg and I get write errors with them all (the ones that supported JDM at least).

I'll probably end up getting a transistor and resistor I need from Radio Shack and build this since it can handle 12f629/75s and at least with the USB power I will know that there isn't a problem programming because of a lack of enough power to the chip. If I ever venture out of 8pin land then the JDM programmer I got may work with them but if not I'll have a good reason to get a nicer programmer.

Thanks again for your help. If I ever get the programmer working with a the chips I will make sure to reply to this thread.

 

I think your idea of building a simple programmer to handle the two devices that your current programmer is unable to program is a good idea. Building your own will give you some experience with the programming hardware.

There has to be a simple explanation for the difficulty you are experiencing in trying to use the JDM programmer to program the 12F629 and 12F675 PICs.

hgmjr

 

Sorry for the bump but thought I'd give an update. Just got done building my JDM and programmed a 12F629 no problem.

 

Congratulations on a successful resolution to your PIC programming problem.

hgmjr