It’s time to teach this relay computer a thing or two about adding 2 + 2. The ALU (Arithmetic Logic Unit) is an integral part of any CPU, and will allow our computer to not only do some basic math, but also lay the foundation for conditional code jumps. Today we build the first of two ALU cards with a little help from our new friends at PCBWay!

If you need custom PCBs, check out PCBWay and get your first $5 free coupon at:
https://pcbway.com/g/1F7ULi

00:00 Intro and Recap
00:55 The ALU
02:31 Half Adders vs. Full Adders
04:05 Prototyping the Full Adder
06:43 Prototyping a Ripple Carry Full Adder
07:53 Design Time Part I (Room to Grow!)
08:27 Conditions Register Prototype
10:37 Zero Detect Prototype
11:37 3 to 8 Function Decoder Prototype
12:51 Design Time Part II
13:30 The PCBWay Experience!
15:07 Arrival of the new ALU boards….and more!
16:01 Build Time
16:56 The manual “shakedown” testing
19:55 The “Lots of Clicks” Automated testing
22:03 Outro
22:26 ASMR Moment and the Return of Turbo Mode

Thank you for watching, and as always I welcome any feedback or ideas for future projects!

Music
Tock Time Warp Tick South London HiFi
Future Proof South London HiFi
It Was a Fine Day South London HiFi
Sun Awakening Futuremono