Added playback controller and testbench

verification/debouncer_tb.sv

@@ -56,8 +56,4 @@ initial begin
     $finish;
 
 end
-
-
-
-
 endmodule

verification/playback_controller_tb.sv

@@ -0,0 +1,106 @@
+/****
+* playback_controller_tb.sv - a testbench for the playback_controller.sv
+*                             module.
+*                             
+* @author: Dilanthi Prentice
+* @date: [unsure of due date]
+*
+* */
+`include "sdvd_defs.sv"
+import sdvd_defs::SPEED;
+
+module playback_controller_tb; 
+    logic clk, reset;
+    logic play, ff;
+    SPEED speed;
+    int errors;
+
+    //instatiate the dut
+    playback_controller dut(clk, reset, play, ff, speed);
+
+    //clock generation
+    initial clk = 0;
+    always #5 clk = ~clk;
+
+    //play button press
+    task press_play();
+        play = 1;
+        @(posedge clk);
+        play = 0;
+        @(posedge clk);
+    endtask
+
+    //ff button press
+    task press_ff();
+        ff = 1;
+        @(posedge clk);
+        ff = 0;
+        @(posedge clk);
+    endtask
+
+    initial
+    begin
+        @(posedge clk);
+        play = 0;
+        ff = 0;
+        
+        reset = 1;
+        @(posedge clk);
+        reset = 0;
+        
+        @(posedge clk);
+        assert (speed === 0) else
+            begin    
+            $error("Speed not zero after reset");
+            errors++;
+            end
+       @(posedge clk);
+        
+        press_play();
+        assert (speed === 1) else
+            begin
+            $error("Play not working");
+            errors++;
+            end
+
+        press_play();
+        assert (speed === 0) else
+            begin
+            $error("Pause not working");
+            errors++;
+            end
+
+        press_ff();
+        assert (speed === 2) else
+            begin
+            $error("Not in FF2 after ff btn pressed once");
+            errors++;
+            end
+
+        press_ff();
+        assert (speed === 4) else
+            begin
+            $error("Not in FF4 after ff btn pressed twice");
+            errors++;
+            end
+        
+        press_ff();
+        assert (speed === 8) else
+            begin
+            $error("Not in FF8 after ff btn pressed thrice");
+            errors++;
+            end
+
+        press_play();
+        assert (speed === 0) else
+            begin
+            $error("Unsuccessful return to pause after play btn pressed from a FF state");
+            errors++;
+            end
+
+        if (errors === 0)
+            $display("No errors detected in playback_controller");
+        
+        $finish;
+    end
+endmodule