MC14500B

The MC14500B Industrial Control Unit is a single bit processor with 16 instructions, and a 4-bit wide instruction bus. It's basically meant to replace relay logic for controlling the sequencing of equipment. In spite of this, it is actually possible to do some math with it, although at 100Khz, it's somewhat slow.

Projects

MC14500B Homebrew Trainer

Trivia

• There is at least one Wikipedia:VHDL implementation of the MC14500B, here (origianl source here).

• I was watching TV a number of years back, when a heating/air-conditioning company (Carrier, I think) bragged about their HVAC unit with a "computer" in it. The ad showed a P.C. board spinning slowly end over end, and as it went by, you could actually read the logo and part number on one of the chips. And it was a MC14500B...

Other resources

• Ken Shirriff's MC14500B blog post
• Usagi Electric's 1-bit breadboard play list
• QR card, misc
• MC14500B links on del.icio.us
• MC14500B Evaluation Board
• Video of a MC14500B implemented in TTL
• Linux-based assembler/disassembler
• Japanese-built Project
• Parallel Forth (491 KB) - Brief mention of the MC14500B

Data Sheets

• Data Sheet (252 KB)
• Handbook (5.17 MB)