Re: [EE] Help with understanding microcontroller markings

What Spehro said, I've had laughably bad fakes, really convincing fakes and
'fake' genuine chips (they'd blacktopped chips with the same markings to
make them look new).

I've also had genuine, untampered chips and, anecdotally, I have the
impression the obscure, unpopular parts are less likely to be faked.

First test is acetone on a cotton swab and visual inspection, they will
often weld new legs onto old/recovered parts and it's obvious when you look
closely, but if they came from a 'trusted' source then I'd suspect they're
previously used or somehow have the bootloader disabled and need ICP
programming rather than ISP.

I ownder if perhaps a standalone programmer like the Dataman units might be
able to program them?

If you're in the UK and wanted to send one device over (which I'd of course
return) I could try mine?


On Mon, 13 Apr 2026 at 06:40, Spehro Pefhany <[email protected]> wrote:

>
> On 2026-04-11 9:46 p.m., William Couture wrote:
> > No, the reels are still sealed.  But being old, something in their FLASH
> > may have decayed.
> >
> > Hmmm... maybe I should check the programming software.  Since it's been
> in
> > production a long time, it probably predates the chips, and a later
> > hardware rev may have tweaked the interface.
> >
> > A new version of the programming software may be needed....
> >
> > Bill
>
>
> Hi, Bill:-
>
> This kind of obsolete and/or in-short-supply  product  is prime
> territory for scammers.
>
> I would not rule out the possibility that you have purchased skillfully
> remarked and repackaged chips that
>
> are lesser or entirely different parts. Or even clones. Try ohm-ing out
> a few pins to see if they behave similarly.
>
> One of the vendors claims 2026 date code, which seems somewhat unlikely
> for a part that had a last-buy date
>
> of June 2016. Could be an innocent mistake.   Another trick is to laser
> re-mark and re-package genuine parts
>
> with a smaller memory such as P89LPC932.  There is a huge variation in
> price on the market from $15+
>
> a part down to pennies, which looks scammy.
>
> I went through something similar with the NXP LPC series about 5 years
> ago. Managed to find a good
>
> supply that lasted until a re-design but got stuck with some bad chips.
>
>
> The middlemen buy and sell chips that are supposedly surplus, so they
> could also be victims of scammers.
>
>
> Best regards,
>
> Spehro Pefhany
>
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-- 
Clint. M0UAW IO83

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