65xx parts sources, genuine and fake

Let's talk about anything related to the 6502 microprocessor.
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SKO
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Re: 65xx parts sources, genuine and fake

Post by SKO »

I just received these Rockwell R6522AP VIAs supposedly manufactured in September 2020 from eBay.

Elsewhere, the global chip shortage may have rocked the world of electronics in 2020, but no fear – Rockwell's Mexican factory happily kept churning out those lovely DIP-40s apparently. They are still listed on eBay. It seems they are working 6522s of some sort (possibly 1 MHz binned parts), and I am not seeing any traces of grinding as you often see with counterfeit chips – if not for the impossible date code, I might have taken these for the genuine article. I find these types of fakes particularly distressing, as genuine, historical 65xx parts are being damaged and made unidentifiable for no good reason.
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BigDumbDinosaur
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Re: 65xx parts sources, genuine and fake

Post by BigDumbDinosaur »

SKO wrote:
I just received these Rockwell R6522AP VIAs supposedly manufactured in September 2020 from eBay.

Those are as fake as a three dollar bill.  :shock:  Rockwell ceased production of 65xx parts 25 years ago.

BTW, there is no good reason to buy dubious 6522s from eBay when you can get the WDC 65C22N, which is a drop-in replacement for the old NMOS part.
x86?  We ain't got no x86.  We don't NEED no stinking x86!
plasmo
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Re: 65xx parts sources, genuine and fake

Post by plasmo »

Compare the bottom of the DIP. Whoever relabeled the parts only do the top side, the bottom is always the original.
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SKO
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Re: 65xx parts sources, genuine and fake

Post by SKO »

plasmo wrote:
Compare the bottom of the DIP. Whoever relabeled the parts only do the top side, the bottom is always the original.
I doubt that. The counterfeiters invest an amazing effort into making ever better fake chips, why would it be unthinkable that some of them modify the bottom side?

Apart from that, the bottom of many chips (including many genuine Rockwell parts as well as these fakes) is unmarked. Others show inscrutable letters and numbers. It would be helpful if one could find more pictures online of the underside of genuine chips, so one would at least know what to expect. Regrettably most people posting images of chips online only show the top side.
plasmo
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Re: 65xx parts sources, genuine and fake

Post by plasmo »

What do the bottoms of your 3 chips look like? If the tops have identical markings and date code, the bottoms should look the same. They don’t re-mark the bottom because there are little identifiable data, but the bottoms need to be the same, including injection molding tool marks.
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sziki04
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Re: 65xx parts sources, genuine and fake

Post by sziki04 »

Hello everybody,

Hopefully I won't break any of the board's rules and sorry for my English skills, but I'm in need some help.

Some time ago I was wondering if I can build a simple, very basic 8 bit computer. I'm not an electrical engineer, I'm mainly a software guy, but I have some basic knowledge of electronics.

One of my friends gave me some ICs, though they are untested and their legitimacy is also questionable.

Could you please help me, are they possibly useable, or unquestionably fake?

Thanks in advance!
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BigDumbDinosaur
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Re: 65xx parts sources, genuine and fake

Post by BigDumbDinosaur »

sziki04 wrote:
One of my friends gave me some ICs, though they are untested and their legitimacy is also questionable.

Could you please help me, are they possibly useable, or unquestionably fake?
Going by the part numbers and date codes, the MPUs in your photos appear to be genuine.
x86?  We ain't got no x86.  We don't NEED no stinking x86!
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gilhad
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Re: 65xx parts sources, genuine and fake

Post by gilhad »

Also I have some chips, which are unquestionably fake, but usable :) (and some genuine, which do not work, because they was electrically damaged, while they physically look still good.) So the definitive answer will be to try the chips and see, if it works or not ... Sockets help there a lot :)
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AndrewP
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Re: 65xx parts sources, genuine and fake

Post by AndrewP »

I've also bought some (allegedly) Rockwell 6502 chips from UTsource that - when they arrived - had definitely been sanded and reprinted.

Not sure why as they bothered as they all worked fine.

If you have an XGecu TL866 II then I've written up a small test definition for the 6502: Testing the (Rockwell) 6502 with an XGecu TL866 II
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