Learn digital logic by touching it
Flip switches, watch signals move through gates, and build working circuits.
⎔
Logic Lab
Description
Learn each topic hands-on: gates, number systems, Boolean algebra, adders, flip-flops, counters and registers.
▦
Logic Solver
Description
Simplify Boolean functions step by step from 2 up to 10 variables: Karnaugh map, Quine–McCluskey, SOP and POS.
⌗
Circuit Builder
Description
A full circuit simulator: gates, flip-flops, ALU, ROM and RAM, feedback loops, timing diagrams, undo, import/export and share links.
✎
Practice
Description
Auto-checked questions for all four units, with a worked explanation after every answer.
Index
Logic Lab15
Digital Computer3
Block diagram6
Input unit
Control unit
ALU
Registers
Memory
Output unit
Instruction cycle4
Fetch
Decode
Execute
Store
Storage3
Bit
Register
Memory: read and write
Logic Gates4
Basic gates4
AND
OR
NOT (inverter)
Buffer
Universal gates2
NAND
NOR
Exclusive gates2
XOR
XNOR
Truth tables and gate symbols
Universal Gates3
Build with NAND only5
NOT
AND
OR
XOR
XNOR
Build with NOR only5
NOT
AND
OR
XOR
XNOR
Check each build against the real gate
Number Systems4
Bit, nibble, byte, word
Base conversion4
Binary
Octal
Decimal
Hexadecimal
BCD
Complements2
r’s complement
(r−1)’s complement
Binary Arithmetic2
Basic operations4
Addition
Subtraction
Multiplication
Division
Subtraction by complements2
Using r’s complement
Using (r−1)’s complement
Boolean Algebra5
Huntington postulates6
Closure
Identity
Commutative
Distributive
Complement
Two elements
Basic theorems
Duality
Operator precedence
Complement and De Morgan’s theorem
Canonical Forms4
Truth table of an expression
Canonical forms3
Minterms (sum of minterms)
Maxterms (product of maxterms)
Conversion between canonical forms
Standard forms2
Sum of products
Product of sums
Minimised result
Combinational Circuits4
Arithmetic circuits4
Half adder
Full adder
Half subtractor
Full subtractor
Magnitude comparator
Code and data circuits4
Decoder
Encoder
Multiplexer
De-multiplexer
Build with4
XOR, AND, OR
AND, OR, NOT
NAND only
NOR only
Design Procedure2
Examples5
Full adder
Full subtractor
BCD to excess-3
2-bit comparator
Your own truth table
Steps4
Specification
Truth table
Simplify each output
Draw and verify the diagram
Flip-flops2
Types6
S-R latch
Clocked S-R
D
J-K
T
Master-slave
Tables and diagrams3
Characteristic table
Excitation table
State diagram
Counters2
Kinds5
3-bit T counter
Ripple counter
BCD counter
Synchronous counter
Up/down counter
Views3
Timing waves
State table
State diagram
Logic Solver4
Circuit Builder3
Gates and lab devices
Wiring and testing with switches and lamps
Save your own chips
Practice6
Mixed
Gates & numbers
Boolean algebra
Circuits
Sequential
Worked explanations