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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:
+ // Put your code here:
+ Mux16 (a=out5, b=in, sel=load, out=out0);
+ Inc16 (in=out0, out=out1);
+ Mux16 (a=out1, b=out0, sel=load, out=out2);
+ Mux16 (a=out0, b=out2, sel=inc, out=out3);
+ Mux16 (a=out3, b=false, sel=reset, out=out4);
+ Register (in=out4, load=true, out=out5, out=out);
+
+ //Inc16 (in=out4, out=out0);
+ //Mux16 (a=out4, b=out0, sel=inc, out=out1);
+ //Mux16 (a=out1, b=in, sel=load, out=out2);
+ //Mux16 (a=out2, b=false, sel=reset, out=out3);
+ //Register (in=out3, load=true, out=out4, out=out);
+}