DigiFlop

Adds three bits — because a carry-in has to go somewhere.

Verilog Coding Exercise · Combinational I
Full Adder
Adds three bits — because a carry-in has to go somewhere.

Extends the half adder with a third input, Cin, so multi-bit adders can be chained together stage by stage.

Boolean expressionsSUM = A ⊕ B ⊕ Cin, COUT = AB + Cin(A ⊕ B)
Good exerciseChain two full adders by hand (Cout of one into Cin of the next) and verify a 2-bit addition.
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