sequential-logic
SISO, SIPO, PISO, PIPO: Shift Register Modes
TL;DR: A shift register is a chain of flip-flops with a shared clock. Pick where the data enters and exits — serially or in parallel — and you get four...
combinational-logic
Static vs Dynamic Hazards in Combinational Logic
TL;DR: A static hazard is a momentary glitch on an output that should have stayed constant; a dynamic hazard is multiple transitions on an output that should have changed exactly...
tri-state-buffer
Tri-State Buffers and Bus Arbitration Explained
TL;DR: A tri-state buffer is a logic gate with three possible outputs — 0, 1, and high-impedance (Hi-Z). The Hi-Z state effectively disconnects the buffer from the wire, allowing multiple...
binary-arithmetic
Two's Complement: Signed Binary Arithmetic Explained
TL;DR: Two's complement is the encoding every modern CPU uses for signed integers. The most significant bit carries weight instead of ; the rest of the bits keep their normal...
oscilloscope
Using the Oscilloscope to Debug Digital Circuits
TL;DR: Drop an OSCILLOSCOPE (2-channel) or OSCILLOSCOPE8CH (8-channel) onto the canvas, wire each channel to the signal you care about, and run the simulation. The waveform window scrolls in real...
relay
How a Relay Works: The Click That Built Modern Computing
Right now, as you read this, something inside your device is flipping switches. Billions of them, billions of times a second, with no moving parts and no sound. But the...
digital-logic-101
Digital Logic 101: Your First Steps with AND, OR, and NOT Gates
TL;DR: AND, OR, and NOT are the three fundamental logic gates. AND outputs 1 only when all inputs are 1; OR outputs 1 when any input is 1; NOT inverts...
boolean-algebra
Boolean Algebra: The Foundation of Digital Circuit Design
TL;DR: Boolean algebra is a formal system for manipulating TRUE/FALSE values using AND, OR, and NOT. Its laws — identity, absorption, distribution, complement, and De Morgan's theorems — let you...
de-morgans-laws
De Morgan's Laws in Practice: NAND-Only Circuit Design
TL;DR: De Morgan's two identities — and — let you swap AND for OR (and vice versa) by distributing inversion. The practical payoff: any logic function can be implemented in...
propagation-delay
Propagation Delay: The Physics That Dictates Digital Speed
TL;DR: Propagation delay () is the finite time between a logic gate's input changing and its output responding — typically a few nanoseconds. The longest such path through a circuit...
nor-gate
The NOR Gate: How It Built Apollo and Powers Modern Logic
TL;DR: The NOR gate outputs 1 only when all inputs are 0 (). Like NAND it is functionally complete — every Boolean function can be built from NOR alone. The...
boolean-algebra
Product of Sums (POS): Boolean Form for Efficient Logic
TL;DR: Product of Sums (POS) is the dual of Sum of Products: instead of ORing minterms for the 1s of a truth table, you AND maxterms for the 0s. POS...
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