BigEd wrote:
By my reckoning, 42 pins is 5% extra... it might be amusing to try to see which pins are inputs, outputs, power supplies. There might be ways of doing that - I'm thinking resistance, capacitance, diode nature.
DIP-42 is not rare but also not common. A quick Google search turned up an answer that actually makes logical sense, and that DIP-42 is most commonly used for types of ROM (most commonly EPROM), with the 2 extra pins obviously being 2 more address lines for larger addressable capacity (vs more common DIP-40). There are also some obscure MCUs that used that package. In all I'd guess that they are used ROM chips that were pulled from recycled boards, sanded down and remarked as fake WDC chips. Looking up a pinout for DIP-42 EPROM should turn up a common pinout, and it's probably it, but honestly I don't think it's even worth the time to check.
BillO wrote:
I would request a refund. They should not be allowed to get away with such nonsense.
I was refunded within a few hours without question, no message. What baited me was some 300+ units sold on that listing, and feedback for those did not indicate fakes. I honestly thought I'd be getting NOS chips, which is perfectly fine by me. These will make a good keychain I guess. Other ideas?
BigDumbDinosaur wrote:
The date codes alone tell me these are counterfeits.
As for a source for the genuine article, it all depends on your location in this world.
Are date codes week number and year? Any code letters?
I'm in the United States. I like DigiKey for all my projects because their shipping rates are great. Sadly WDC is not among the manufacturer's whose products they sell.
https://www.digikey.com/en/supplier-centers#WI also like Jameco, they were a one-stop-shop for all replacement chips in the boat anchor Commodore 64 I was restoring, the prices were good and the shipping was fine also. They don't carry WDC processors either.
I avoid Mouser whenever I can, they are more expensive and their shipping rates just plain suck, and they take longer to process orders than the two above. If I shop there I usually wait to accumulate a large order to justify their shipping.