DigiFlop

Two bits in, sum and carry out — the simplest adder there is.

Verilog Coding Exercise · Combinational I
Half Adder
Two bits in, sum and carry out — the simplest adder there is.

Adds two single-bit numbers A and B, producing a SUM and a CARRY output. It has no way to accept an incoming carry, which is exactly the limitation the full adder fixes.

Boolean expressionsSUM = A ⊕ B, CARRY = A · B
Good exerciseSimulate all 4 input combinations and confirm SUM/CARRY match the truth table by hand.
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