1
Numbers & codes — how a machine holds information
Topic 01
Why digital?
The world is analog, but the machine is digital — why every modern system thinks in 1s and 0s.
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Topic 02
Number bases & place value
One idea — place value — writes the same number in decimal, binary and hex.
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Topic 03
Base conversions
The same number, translated between decimal, binary and hexadecimal.
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Topic 04
Binary addition
The simplest thing a computer does with numbers — four rules and a carry.
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Topic 05
Two's complement & signed numbers
There is no minus-sign wire in a chip — this is how negatives are encoded.
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Topic 06
Fixed & floating-point
Integers can't hold 6.625 — the two ways a machine represents real numbers.
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Topic 07
Register maps: reading a byte
Where it all pays off — a single byte is a chip's control panel.
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2
Boolean logic — the algebra of gates
Topic 08
Boolean basics & the AND/OR/NOT gates
The three primitive gates and the algebra that describes them.
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Topic 09
Truth tables
The complete, unambiguous way to describe what a logic circuit does.
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Topic 10
The derived gates
Four more gates from the first three — and the two that can build anything.
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Topic 11
Boolean theorems & simplification
The algebra rules that shrink an expression — fewer gates, less power.
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Topic 12
DeMorgan's theorem
The single most useful identity in digital design — pushing a NOT through a group.
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Topic 13
From English to a Boolean expression
Turn a written requirement — a safety rule — into logic you can build.
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3
Minimisation — K-maps & canonical forms
4
Combinational building blocks — from adders to the ALU
Topic 17
The combinational design method
A repeatable recipe: turn a sentence into a working circuit.
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Topic 18
The adder: half → full
The circuit that adds binary, carries and all — built from gates.
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Topic 19
The ripple-carry adder
Line up full adders, each carry feeding the next — add many bits at once.
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Topic 20
The adder/subtractor
One control bit turns your adder into a subtractor too — no second circuit.
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Topic 21
The magnitude comparator
A circuit that returns a verdict: is A bigger than, equal to, or less than B?
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Topic 22
Multiplexer & demultiplexer
Blocks that move data instead of computing it — select one of many.
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Topic 23
Decoder & encoder
Turn a compact binary code into one active line — and back again.
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Topic 24
Meet the ALU
Every block in this stage was practice for one machine: the arithmetic logic unit.
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