Many Changes

I added a comparator, I updated the control unit so that it now uses the 4 bit ALU opcode instead of the 3 bit from before. I added testbenches to the control unit and the slt and comparator modules. However, like before I unable to run the simulation on my desktop. Finally, i added the program code for the equation solver as a test bench in the CPU9bit module

lab2CA.srcs/sources_1/new/BasicModules.v

@@ -215,6 +215,49 @@ module and9bit_tb();
     end
 endmodule
 
+module comparator (
+    input wire [8:0] A,
+    input wire [8:0] B,
+    output wire [8:0] C);
+
+    assign C = (~A & ~B) | (A & B);
+
+endmodule
+
+//testbench
+module comparator_tb();
+    reg [8:0] a,b;
+    wire [8:0] c;
+
+    comparator comparator0(
+        .A(a),
+        .B(b),
+        .C(c));
+    
+    initial begin
+        a = 9'b000000000;
+        b = 9'b000000000;
+        #5
+        a = 9'b000000000;
+        b = 9'b000000001;
+        #5
+        a = 9'b000000001;
+        b = 9'b000000000;
+        #5
+        a = 9'b000000001;
+        b = 9'b000000001;
+        #5
+        a = 9'b000100001;
+        b = 9'b000000001;
+        #5
+        a = 9'b000100001;
+        b = 9'b000100001;
+        #5
+        $finish;
+
+    end
+endmodule
+
 module decoder (
     input wire en,
     input wire [1:0] index,
@@ -887,36 +930,30 @@ endmodule
 module slt (
     input wire en,
     input wire [8:0] inA, inB,
-    output reg outA);
+    output reg [8:0] outA);
     
     always @(inA, inB)begin
         if (inA < inB) begin
-            outA = 1;
+            outA = 9'b000000001;
         end
         else begin
-            outA = 0;
+            outA = 9'b000000000;
         end
     end
 endmodule
 
 //testbench
 module slt_tb();
-    reg enable;
     reg [8:0] indexA;
     reg [8:0] indexB;
     wire outputA;
 
     slt slt0(
-        .en(enable),
         .inA(indexA),
         .inB(indexB),
         .outA(outputA));
     
     initial begin
-        enable = 0;
-        #5
-        enable = 1;
-        #5
         indexA = 9'b000000000;
         indexB = 9'b000000000;
         #10