Treasure hunt victory. Just found a DEC F-11 CPU from Shenzhen. The second-generation of LSI-11, PDP-11 on a chip.

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Just received the DEC F-11 CPU from my previous treasure hunt. This is the chip that powered the second generation of LSI-11 machines, including PDP-11/23 and PDP-11/24. Now I'm a proud owner of a PDP-11 on a chip.

You can still find some in the USA, but I never expected to find one in China. But not surprising, I can imagine that someday, somewhere in Guiyu, a container full of scrapped industrial equipment arrived, one of them was a PDP-11 (or perhaps only a KDF11 CPU board), it was sold as scrap metal and got scavenged here.

More treasure hunt victory from Shenzhen: Intersil IM-6100, IM-6100A and Harris HD-6120 CPUs - PDP-8-on-a-chip! Also known as "CMOS-8s".

My PDP-8 microprocessors arrived - Intersil IM-6100 and Harris HD-6120 CPUs. They're PDP-8-on-a-chip, also known as "CMOS-8". I received them a month ago but forgot to take a photo. Now I need to bring the computer back to life.

@roytam1 J-11 has extensive chip-level documentation, but F-11 is more difficult, I only found system-level documentation and schematics for the KDF-11 CPU board. If I cannot find anything better, it's necessary to work backward from schematics.

@roytam1 Yep, I saw that one too. Need to do some "reverse-engineering" (in quote marks) from the schematics.

@niconiconi I think it might be easier to find USSR clones than genuine one in China.

@roytam1 I really want to get some USSR clones, the problem is all the documentation is in Russian.

@phooky I guess the selling point here was 12-bit ADC interfacing.

@niconiconi I have an unknown IC of that vintage, it looks remarkably like the top one (purple with gold stripe, the cap in the center is black though). I think it came out of a modem, probably from the PDP era.

AMI 8044FG
404-0212 L2

It's in rough shape. I glued it to a holiday decoration as a teen. It's still got bits of craft glue and fuzz stuck to a couple of the legs 😁

@niconiconi at various points I've been very tempted to buy one of the soviet PDP-11-on-a-chip designs on ebay

@izaya I'd love to buy them but I can't read Russian datasheets...

@niconiconi @izaya I wonder if @rin might know someone who knows russian, is into retrocomputing, and could help

@kumicota @wolf480pl @niconiconi @rin there's the bonus hurdle of the fact that most of them I've seen are in cursed packages like QIP28, with two rows of 14 pins on either side.
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