M projects/02/ALU.hdl → projects/02/ALU.hdl

@@ -42,5 +42,26 @@ zr, // 1 if (out == 0), 0 otherwise
         ng; // 1 if (out < 0),  0 otherwise
 
     PARTS:
-   // Put you code here:
-}+    Mux16(a=x, b=false, sel=zx, out=x-or-zero);
+    Mux16(a=y, b=false, sel=zy, out=y-or-zero);
+
+    Not16(in=x-or-zero, out=not-xoz);
+    Not16(in=y-or-zero, out=not-yoz);
+
+    Mux16(a=x-or-zero, b=not-xoz, sel=nx, out=x-arg);
+    Mux16(a=y-or-zero, b=not-yoz, sel=ny, out=y-arg);
+
+    Add16(a=x-arg, b=y-arg, out=add-xy);
+    And16(a=x-arg, b=y-arg, out=and-xy);
+    Mux16(a=and-xy, b=add-xy, sel=f, out=func-out);
+
+    Not16(in=func-out, out=not-func-out);
+    Mux16(a=func-out, b=not-func-out, sel=no, out[0..7]=or8-in1,
+                                              out[8..15]=or8-in2, out[15]=ng,
+                                              out=out);
+
+    Or8Way(in=or8-in1, out=or8-1);
+    Or8Way(in=or8-in2, out= or8-2);
+    Or(a=or8-1, b=or8-2, out=not-zr);
+    Not(in=not-zr, out=zr);
+}

M projects/02/PROGRESS.md → projects/02/PROGRESS.md

@@ -1,11 +1,9 @@ 
 
 # Progress
 
-## TODO
-ALU
-
 ## DONE
 Add16
+ALU
 FullAdder
 HalfAdder
 Inc16