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Today I was taking apart an old typewriter and I have this IC that was in a socket. I took it out and started searching online to see what this IC does. I spent 20 minutes and nothing showed up about it. It is a

 NEC 833IE9
 D2364EC 071.  

Any Help?

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The question has insufficient information for a definitive answer, a photo would help.

Going by the description of it being a 24-pin device, and that it was socketed (which implies DIP, and also suggests replacement being a maintenance option), it could be this NEC ROM device: nMOS μPD2364, 64 kilobit, 5 Volt TTL ROM, programmed at fabrication by the manufacturer.

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A little more info might be helpful. What package is it in? What does it seem to be doing in the circuit? Without really any more detail my first guess would be this part.

In other words I think it's a ROM (read only memory) chip. I can't find anywhere selling them so they probably don't manufacture them anymore. (It is a old typewriter after all.) Is it near a micro or an fpga or something? That might help us figure out the mystery.

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