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Greetings list,
I am using the MElabs serial programmer. It worked great for years, until I plugged it in this morning. No green light. I checked all power connections and regulators, but it all tests good. I also get a "no communications" box from the PC I am working with.
Other than an 18F252 that decided to stop working, any ideas for trouble shooting?
Thanks,
Ron
How about the Crystal?
Q1, Q2, Q3?
Possible to have a faulty DB9 cable?
Possible to have some break-link between the DB9 and the circuit?
Broken pins on the dip socket?
Do you have a way to check the com port? You might have a bad port.
Or may be they inserted a secret timer/counter inside the programmer to terminate the life of it; and now it is time to buy a new one.
I am a great conspiracy theorist!
Sorry, I haven't checked the list in a few hours. I replaced the crystal, and checked the com port. I normally get the green light on power up whether it's hooked up to the PC or not. Does the chip do a diagnostic on the transistors on power up?
Otay... I spoke to Charles at MElabs. He told me that occasionally, the PIC252 just goes astray. About a dozen have, with no aparent cause. I ordered another chip and will update the list if this works. The board is so simple, I can't believe that it won't.
Thanks for the input,
Ron
Received the new PIC controller for the serial programmer. Fired it up, and that did the trick. Thanks for the input.
Ron