Usagi Electric | Reverse Engineering the Motorola MC14500 1-bit CPU @UsagiElectric | Uploaded February 2021 | Updated October 2024, 15 hours ago.
This is a special one! In this episode we tell one of the most epic stories and take a look at some truly amazing die shots of the Motorola MC14500 1-bit CPU. Some truly amazing people helped with this journey, so please, absolutely check out the links below!

EDIT:

Ken has hooked me up with one more little nugget of brilliance. The skip function that we look at at the end can be summarized much better by looking at the right most group of transistors as a NAND gate. Check this image: https://i.postimg.cc/zfyBWNRR/NAND-SKZ.jpg


That's a much more elegant way to decipher that!
Thank you again Ken!

Zoomable die shot of the metal: siliconpr0n.org/map/motorola/mc14500/mz_mit20x

Zoomable delayered die shot: siliconpr0n.org/map/motorola/mc14500/s1-2_mit20x

Ken’s blog post on the MC14500: righto.com/2021/02/a-one-bit-processor-explained-reverse.html

Hackaday: hackaday.io
Our HackChat transcript: hackaday.io/event/175628-vacuum-tube-logic-hack-chat
All HackChat transcripts: hackaday.io/event/19578-hack-chat-transcripts

CuriousMarc’s channel: youtube.com/user/mverdiell

Ken Shirriff’s blog: righto.com

John McMaster’s homepage: siliconpr0n.org

Falstad: falstad.com/circuit/circuitjs.html
Falstad simulation of the Skip circuit: tinyurl.com/y7nb5x42


Come join us on Discord!

Discord: discord.gg/p7UsfHD
Twitter: twitter.com/UsagiElectric

Thanks for watching!