- Event-Driven Discrete Simulation
- TTL 74xx & CMOS 40xx Libraries
- State Snapshot Testing
- Interactive Breadboard GUI
DIGITAL ELECTRONICS / LOGIC SIMULATION
Event-Driven Logic Simulation for TTL and CMOS IC Families
Unlike analog circuits that require continuous Modified Nodal Analysis (MNA), digital circuits operate on discrete logic states. The 74xx40xx simulator is an event-driven digital logic simulation engine designed to model the exact pin behavior, propagation delays, and state transitions of standard 74xx TTL and 40xx CMOS integrated circuits.
Event-driven simulation engine
State transitions on input pins schedule propagation events that evaluate gate logic only when inputs change. This avoids polling cycles and accurately replicates propagation delays and hazard conditions.
Modular device hierarchy (DigitalIC)
Structured around an extensible DigitalIC base class. Supports standard logic gates, flip-flops (D, JK, T), synchronous 4-bit counters (74161/74163), shift registers (74194), decoders, and full ALUs (74181).
State management & snapshot testing
Features dictionary-based state modeling with the DigitalICState class. Every chip supports clean resets and state serialization, enabling unit testing of complex sequential logic without hardware probes.
Interactive GUI & virtual lab testbench
Provides an interactive breadboard interface where students and engineers can drop IC packages, wire DIP pins, toggle logic levels, inject clock pulses, and inspect output LEDs in real time.
Supported IC Families & Capabilities
- Engine Design
- Event-driven digital simulation with discrete propagation delay modeling
- TTL 74xx Series
- 7400 (NAND), 7402 (NOR), 7404 (NOT), 7408 (AND), 7432 (OR), 7486 (XOR)
- Sequential Logic
- 7474 (D-Flip-Flop), 7476 (JK-Flip-Flop), 74161 (Synchronous 4-Bit Counter)
- Complex Functions
- 74138 (3-to-8 Decoder), 74194 (Universal Shift Register), 74181 (4-Bit ALU)
- CMOS 40xx Series
- 4001 (Quad NOR), 4011 (Quad NAND), 4013 (Dual D-Type), 4017 (Decade Counter)
- Architecture / Toolchain
- C# · .NET Core · Unit Tests · GUI Testbench
Educational & Engineering Relevance
Built for hardware education and digital design validation, bridging the gap between theoretical gate schematics and practical integrated circuit pinout wiring.