26 lines
847 B
Plaintext
26 lines
847 B
Plaintext
// 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:
|
|
// Put your code here:
|
|
Inc16(in=registerValue, out=incrementedValue);
|
|
Mux16(a=registerValue, b=incrementedValue, sel=inc, out=incBitStep);
|
|
Mux16(a=incBitStep, b=in, sel=load, out=loadBitStep);
|
|
Mux16(a=loadBitStep, b=false, sel=reset, out=resetBitStep);
|
|
Register(in=resetBitStep, load=true, out=out, out=registerValue);
|
|
}
|