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// This file is part of www.nand2tetris.org
// and the book "The Elements of Computing Systems"
// by Nisan and Schocken, MIT Press.
// File name: projects/03/a/PC.hdl
/**
* A 16-bit counter with load and reset control bits.
* if (reset[t] == 1) out[t+1] = 0
* else if (load[t] == 1) out[t+1] = in[t]
* else if (inc[t] == 1) out[t+1] = out[t] + 1 (integer addition)
* else out[t+1] = out[t]
*/
CHIP PC {
IN in[16],load,inc,reset;
OUT out[16];
PARTS:
Register(in=fb, load=true, out=reg, out=out);
Inc16(in=reg, out=reg1);
Mux16(a=reg, b=reg1, sel=inc, out=cnt);
Mux16(a=cnt, b=in, sel=load, out=cntin);
Mux16(a=cntin, b=false, sel=reset, out=fb);
}
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