The course begins with one bit. By the end of the week you have built a 4-bit ripple adder out of NAND gates on a breadboard and understood why a NAND gate is enough to build any logic circuit ever made.
Reading
- Chapter prose (primary). draft-chapters/ch1-boolean-logic-prose.md
- Petzold weave anchors. Ch 4 (Anatomy of a Flashlight, p. 22), Ch 6 (relay/repeater, p. 44), Ch 11 (Gates (Not Bill), p. 129 De Morgan equivalences). ~30 pages, 1st edition.
- Cross-chapter handouts. Petzold reading guide (bookmark for the entire course); HW-101 anchor reading guide if you came in light on bench instruments.
Lecture
lectures/ch1-boolean-logic-lecture.md. 3 hours. Key arc:
- Why one bit. Why Boolean values. The flashlight as the smallest circuit
- AND, OR, NOT as switch arrangements. Truth tables as the contract
- NAND universality. Any circuit can be built from NAND alone
- De Morgan's laws as electrical equivalences (Petzold weave anchor)
- Forward pointer to Ch 2: adding two bits is the first useful circuit
Lab exercises
Five labs in worksheets/ch1/. Pick the ones that match your equipment access (full breadboard kit; or browser-only via the workbench).
- lab-1.0-discrete-logic-breadboard.md, ~90 min, prereq lab
- lab-1.1-flashlight-breadboard.md, the first circuit; ~60 min
- lab-1.2-morse-telegraph.md, the relay pattern from Petzold; ~90 min
- lab-1.3-nand-only-gates.md, NAND universality demonstrated; ~90 min
- lab-1.4-4bit-ripple-adder.md, the first useful circuit; ~120 min
Plan for ~5 hours of lab. Browser-path students do labs 1.3 + 1.4 in the workbench; bench-path students do the full discrete-logic build-up.
Independent practice
- Read the three Petzold weave anchors carefully. Note the page numbers and theses; they recur throughout the course
- Start your Toolchain Diary at
~/student-repo/toolchain-diary.mdper worksheets/TEMPLATE-toolchain-diary.md. Week 1 introduces: breadboard, multimeter, logic probe (or workbench equivalents) - Optional: read nand2tetris Ch 1 if you have a copy. Same structural arc; different idiom
Architecture comparison sidebar
Why NAND is universal in every silicon family ever shipped. Every transistor-level CMOS gate the planet manufactures inherits the same universality theorem you just demonstrated on the breadboard. Patterson-Hennessy and Petzold both anchor here for the same reason: it is the smallest reusable claim in computing.
Reflection prompts
- The flashlight has one switch and one light. The 4-bit ripple adder has dozens of gates. What stayed the same about the engineering across the scale-up?
- If NAND is universal, why did your kit include AND and OR chips? What pressure decides which gates the silicon vendor packages?
- Petzold spent Ch 4 to Ch 11 building toward gates. We arrived at the same place in one week. What did Petzold's slow climb give the reader that our compressed version did not?
What's next
Week 2 takes the 4-bit ripple adder you just built and grows it to a 32-bit ALU. Same engineering ideas; one order of magnitude bigger.