Two dead 16F877A and one 16F628A duff eeprom

[tasmod]

I suddenly seem to have perhaps a static electricity problem. What do you think ?

In one day I have two 16F877A 's that will program and verify but are dead in every other respect to ports. The crystal will oscillate but a simple ports blink LED program won't light them up.

I also have a 16F628a that reports as 'Bad eeprom address' when programmed.

Bit of a letdown.

[Chirpy]

what type of programmer do you have? I had an offbrand pickit2 that when it started to become faulty, it'd cause the same symptoms that your experiencing, the chips were fine, but the programmer was fine.
I know some jdm programmers, if there isnt enough power on the serial port, it will cause issues like that too.

[tasmod]

I realise now what may be the cause.

Shame, never blown a chip in 20 years of cmos etc

I originally had a worn leather executive chair at the bench, it always annoyed me as it was just too wide for the opening and prevented me opening the work drawers unless I pulled back. I recently changed it for a typist style chair with arms which is narrower, now I can open the drawers without moving back.

Unfortunately two things:-
one: it has a synthetic cloth seat and plastic castors.
two: I bought a plastic over carpet mat to help movement.

Seems these two are perfect static generators. I use a self healing craft mat on bench top, I suppose I'll have to invest in an anti-static mat and a wrist band now.

[Jumper]

Well you can try to steal some fabric softener from your wife. Mix it quite generously so the water gets a bit milky and use this to mop the floor and carpet. You can also soak the chair with this and wipe the work area. Let the solution dry and then pet the cat to see if it becomes better.

One of the biggest reason to use softener in the washing machine is not the nice smell it is actually to reduce static electricity when wearing the clothes.

I do not say ESD wrist band is a bad idea, I just say raid the house first :-).

[Darrel Taylor]

PIC chips are extremely tough little buggers.

Here in Colorado Springs the humidity hangs around 10% most of the time.
We'll draw 1/8" to 1/4" arcs when you touch anything, even if it's not grounded.
You can draw an arc touching a wood door. I've never seen anywhere quite like it.

I do not use any kind of static wrist bands or mats.
We have several hundred different PIC's in the office, and to my knowledge not a one has been toasted by a static discharge.

If we're passing a circuit board between two people, we'll set it down on a table and let the other person pick it up.
But that's mainly because person to person arcs are huge.
The PCB is likely to go flying just from your arm jerking away from the pain. But the chip will be fine.

So I'd look at other possibilities before buying a bunch of anti-static equipment.

------------------------- --------------------------------

For the bad address error, ... programmers don't look at the chip to see if an EEPROM address is valid or not.
They look up the address ranges from a database or parameter file.
If the EEPROM wasn't working, you would most likely get a Verify Error instead.

And the 877A's don't sound like dead chips either, but it's hard to tell without more information.

What programmer are you using?
What are the configs set to?

[Acetronics2]

Considering the cost of a Pickit 2 ...

you shouldn't hesitate to have a " reference" really working tool .

just my two cents ...

Alain

[Ioannis]

10% humidity? Wow! I suppose you have a very good comfort feeling there!

My town is normally around 50 to 70%, at nights over 80%. When it blows from north things are much better with 20-30%.

Thats when we experience some arcs in social relations. Normally there is no problem with static around although I play on the safe side with mat on the floor and workbench, wearing also a wrist band too.

Ioannis

P.S. Alain is right about the reference tool. By the way I wonder why on Pickit3 they do not offer a UART tool? Newer is not always more flexible.

[Dick Ivers]

Chirpy, By any chance was your clone PICkit 2 an iCP01 by piccircuit.com? I have one and it seems OK ... I hope.

[Chirpy]

no, the iCP01 seemed to be kinda cheap made for me, so I just got the sure electronics clone. Its an identical clone of the official pickit2. Also alot of people said a bunch bad about the company, but Ive never had any issues with mine, and I use it almost nonstop.

[tasmod]

OK a bit of an update.

I had problems with two more f628a's where the programmer threw up a Bad Rom error. So i borrowed a friends identical programmer and it programmed the f628s just fine. I did some more code work and attempted to program the chips for about the fifth time when the error appeared again using my friends programmer.
From then on every time I tried I got an error.

I couldn't work it out. I then closed the laptop etc and went away leaving it all for a day.
When i returned first thing i did was to try programming a 628 and it worked fine! More code changes etc and then somewhere further down the line the eeprom code error appeared again. I closed down, waited a while and restarted the laptop. Same again it programmed just fine for quite a while before the code error appeared again. (I'm working on three projects in 628s)

So something is wrong either with the code, laptop, MPASM compiling or the programmer software. I suspect the programmer software as it's a cheapo.

I haven't yet tested the 877s which have been programmed indepenently elsewhere. The pcb isn't finished and I don't want to disturb anything.

I now think static has nothing to do with my problems, especially after Darrels info.

In use:
MicroCode Studio Editor
MPASM for compiling (at moment DDS asm files)
Ebay 149 kit type programmer. (Always been fine)

[Ioannis]

On your programmer is there an option to erase before programming the chip?

If yes, selecting this option, does make any difference?

Ioannis

[tasmod]

Yes, I tried that route but it still threw up the error.

Seems a total system shutdown for a while will allow programming after restart. This lasts for a while before the error appears again.

[Acetronics2]

Hi,

Laptop AND Programmer generally gives a really bad cocktail ...

Did you try behaviour aboard a good ol' "wardrobe" computer ??? ...

Alain