21 lines
503 B
VHDL
21 lines
503 B
VHDL
// This file is part of www.nand2tetris.org
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// and the book "The Elements of Computing Systems"
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// by Nisan and Schocken, MIT Press.
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// File name: projects/02/FullAdder.hdl
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/**
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* Computes the sum of three bits.
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*/
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CHIP FullAdder {
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IN a, b, c; // 1-bit inputs
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OUT sum, // Right bit of a + b + c
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carry; // Left bit of a + b + c
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PARTS:
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HalfAdder(a=b, b=c, sum=is, carry=carry1);
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HalfAdder(a=a, b=is, sum=sum, carry=carry2);
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Or(a=carry1, b=carry2, out=carry);
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}
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