timing
Clock Skew and Its Effect on Timing
TL;DR: Clock skew is the difference between when a clock edge arrives at one flip-flop and when it arrives at the next. Positive skew (the receive flip-flop sees the edge...
cpu-architecture
CPU Flags Register: Carry, Zero, Overflow, Sign
TL;DR: A CPU flags register stores four single-bit results from the most recent ALU operation: Zero (Z) when the result is zero, Carry (C) on unsigned overflow, Negative/Sign (N) equal...
demultiplexer
Demultiplexer Tutorial: 1-to-4 and 1-to-8 (DEMUX)
TL;DR: A demultiplexer (DEMUX) is a combinational circuit that takes one data input and routes it to one of output lines, with the destination chosen by an n-bit select code....
comparison
DigiSim vs CircuitVerse: Which to Pick
TL;DR: DigiSim.io and CircuitVerse are both solid browser-based digital logic simulators. CircuitVerse wins if open source and "completely free forever" are your top priorities; DigiSim wins if curated animated lessons,...
comparison
DigiSim vs Logisim Evolution: An Honest Comparison
TL;DR: DigiSim.io wins on browser-native, animated lessons, multilingual UI, and modern UX; Logisim Evolution wins on open-source licensing, mature classroom adoption, offline use, and the .circ ecosystem. Most courses can...
comparison
DigiSim vs Tinkercad Circuits: Which Fits Your Class
TL;DR: Tinkercad Circuits and DigiSim solve different problems — Tinkercad for Arduino, breadboards, and analog electronics; DigiSim for pure digital logic from gates up to CPU architecture. They're not really...
comparator
Digital Comparator Explained: Equality and Magnitude
TL;DR: A digital comparator is a combinational circuit that compares two N-bit binary numbers and outputs whether they are equal, or which one is larger. An equality comparator is built...
learning-roadmap
Digital Logic Roadmap: From Gates to CPU in 30 Days
TL;DR: Thirty days, four weeks, one structured path from your first AND gate to a working CPU you have wired together yourself. Each day pairs one blog post (the theory)...
boolean-algebra
Don't-Care Conditions in Karnaugh Maps
TL;DR: A don't-care is an input combination whose output value either cannot occur or simply does not matter. On a Karnaugh map, mark it with X and include it in...
embed
Embed an Interactive Circuit in Your Lesson or Blog
TL;DR: Any DigiSim template circuit has a clean iframe URL of the form https://digisim.io/circuits/embed/template/<slug?theme=dark&toolbar=false&interact=true. Drop that into an <iframe in your LMS, blog, or notes app and your readers get...
cpu-architecture
Endianness: Big vs Little (with Bus Diagrams)
TL;DR: Endianness is the convention for how a multi-byte value is laid out in memory. Big-endian stores the most-significant byte at the lowest address (network protocols, PowerPC); little-endian stores the...
comparison
Free Online Circuit Simulators Compared (2026)
TL;DR: No single free online circuit simulator is best at everything in 2026 — CircuitVerse for open-source digital logic, DigiSim free tier for curriculum and CPU components, Tinkercad for Arduino...
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