Refactor KittCar and KittCarPWM for improved LED control; update simulation settings and add testbench

LAB1/sim/tb_KittCarPWM.vhd

@@ -0,0 +1,85 @@
+LIBRARY IEEE;
+USE IEEE.STD_LOGIC_1164.ALL;
+USE IEEE.NUMERIC_STD.ALL;
+
+ENTITY tb_KittCarPWM IS
+END tb_KittCarPWM;
+
+ARCHITECTURE testbench OF tb_KittCarPWM IS
+    -- Test constants
+    CONSTANT CLK_PERIOD : TIME := 10 ns;
+    CONSTANT RESET_TIME : TIME := 10*CLK_PERIOD;
+    CONSTANT TEST_DURATION : TIME := 10000 ms;
+
+    CONSTANT PERIOD : TIME := 10ms;
+
+    -- Signals
+    SIGNAL clk : STD_LOGIC := '0';
+    SIGNAL reset : STD_LOGIC := '0';
+    SIGNAL sw : STD_LOGIC_VECTOR(15 DOWNTO 0) := (OTHERS => '0');
+    SIGNAL led : STD_LOGIC_VECTOR(15 DOWNTO 0);
+
+    -- Device Under Test (DUT) instance
+    COMPONENT KittCarPWM
+        GENERIC (
+            CLK_PERIOD_NS : POSITIVE := 10;
+            MIN_KITT_CAR_STEP_MS : POSITIVE := 1;
+            NUM_OF_SWS : INTEGER := 16;
+            NUM_OF_LEDS : INTEGER := 16;
+            TAIL_LENGTH : INTEGER := 4
+        );
+        PORT (
+            reset : IN STD_LOGIC;
+            clk : IN STD_LOGIC;
+            sw : IN STD_LOGIC_VECTOR(NUM_OF_SWS - 1 DOWNTO 0);
+            led : OUT STD_LOGIC_VECTOR(NUM_OF_LEDS - 1 DOWNTO 0)
+        );
+    END COMPONENT;
+
+BEGIN
+    -- Connect DUT
+    dut_KittCarPWM : KittCarPWM
+    GENERIC MAP (
+        CLK_PERIOD_NS => 10,
+        MIN_KITT_CAR_STEP_MS => 1,
+        NUM_OF_SWS => 16,
+        NUM_OF_LEDS => 16,
+        TAIL_LENGTH => 4
+    )
+    PORT MAP (
+        reset => reset,
+        clk => clk,
+        sw => sw,
+        led => led
+    );
+
+    -- Clock generation process
+    clk <= not clk after CLK_PERIOD/2;
+
+    -- Reset Process
+    reset_wave :process
+	begin
+		reset <= '1';
+		wait for RESET_TIME;
+		
+		reset <= not reset;
+		wait;
+    end process;
+
+    -- Test process
+    stim_proc : PROCESS
+    BEGIN
+        -- wait for reset
+        sw <= "0000000000000000";
+        WAIT FOR RESET_TIME;
+
+        -- Start
+        for I in 0 to 2**16-1 loop
+            sw <= std_logic_vector(to_unsigned(I, 16));
+            WAIT FOR PERIOD;
+        end loop;
+
+        -- End simulation
+        WAIT;
+    END PROCESS;
+END testbench;

LAB1/src/KittCar.vhd

@@ -33,27 +33,30 @@ ARCHITECTURE Behavioral OF KittCar IS
     CONSTANT MIN_KITT_CAR_STEP_NS : UNSIGNED(46 DOWNTO 0) := to_unsigned(MIN_KITT_CAR_STEP_MS * 1000000, 47);
 
     SIGNAL leds_sr : STD_LOGIC_VECTOR(led'RANGE) := (OTHERS => '0');
-    SIGNAL n_period : UNSIGNED(NUM_OF_SWS DOWNTO 0) := to_unsigned(1, NUM_OF_SWS + 1);
-    SIGNAL up : STD_LOGIC := '1';
 BEGIN
 
     -- Sincronous logic
     PROCESS (clk, reset)
         VARIABLE counter : UNSIGNED(46 DOWNTO 0) := (OTHERS => '0');
+        VARIABLE n_period : UNSIGNED(NUM_OF_SWS DOWNTO 0) := to_unsigned(1, NUM_OF_SWS + 1);
+        VARIABLE up : STD_LOGIC := '1';
     BEGIN
         IF reset = '1' THEN
             leds_sr <= (OTHERS => '0');
             counter := (OTHERS => '0');
         ELSIF rising_edge(clk) THEN
 
+            -- Handle the switch
+            n_period := unsigned('0' & sw) + 1;
+
             -- Kitt logic
             IF unsigned(leds_sr) = 0 THEN
                 leds_sr(0) <= '1';
-                up <= '1';
+                up := '1';
             ELSIF leds_sr(led'HIGH) = '1' THEN
-                up <= '0';
+                up := '0';
             ELSIF leds_sr(led'LOW) = '1' THEN
-                up <= '1';
+                up := '1';
             END IF;
 
             -- Increment the counter
@@ -75,12 +78,6 @@ BEGIN
         END IF;
     END PROCESS;
 
-    -- Handle the switch
-    PROCESS (sw)
-    BEGIN
-        n_period <= unsigned('0' & sw) + 1;
-    END PROCESS;
-
     led <= leds_sr;
 
 END Behavioral;

LAB1/src/KittCarPWM.vhd

@@ -32,10 +32,7 @@ END KittCarPWM;
 ARCHITECTURE Behavioral OF KittCarPWM IS
     COMPONENT PulseWidthModulator
         GENERIC (
-            BIT_LENGTH : INTEGER RANGE 1 TO 16;
+            BIT_LENGTH : INTEGER
-            T_ON_INIT : POSITIVE;
-            PERIOD_INIT : POSITIVE;
-            PWM_INIT : STD_LOGIC
         );
         PORT (
             reset : IN STD_LOGIC;
@@ -47,88 +44,79 @@ ARCHITECTURE Behavioral OF KittCarPWM IS
         );
     END COMPONENT;
 
-    TYPE led_reg IS ARRAY (TAIL_LENGTH - 1 DOWNTO 0) OF INTEGER RANGE 0 TO led'HIGH;
+    TYPE leds_sr_type IS ARRAY (TAIL_LENGTH - 1 DOWNTO 0) OF INTEGER RANGE led'LOW TO led'HIGH;
     
     CONSTANT MIN_KITT_CAR_STEP_NS : UNSIGNED(46 DOWNTO 0) := to_unsigned(MIN_KITT_CAR_STEP_MS * 1000000, 47);
-    CONSTANT BIT_LENGTH : INTEGER RANGE 1 TO 16 := 8;
+    CONSTANT BIT_LENGTH : INTEGER := 5;
+
+    SIGNAL pwms : STD_LOGIC_VECTOR(TAIL_LENGTH - 1 DOWNTO 0) := (OTHERS => '0');
+    SIGNAL leds_sig : STD_LOGIC_VECTOR(NUM_OF_LEDS - 1 DOWNTO 0) := (OTHERS => '0');
 
-    SIGNAL leds_sr : led_reg := (OTHERS => 0);
-    SIGNAL leds_pwm : STD_LOGIC_VECTOR(TAIL_LENGTH - 1 DOWNTO 0) := (OTHERS => '0');
-    SIGNAL led_sig : STD_LOGIC_VECTOR(NUM_OF_LEDS - 1 DOWNTO 0) := (OTHERS => '0');
-    SIGNAL n_period : UNSIGNED(NUM_OF_SWS DOWNTO 0) := to_unsigned(1, NUM_OF_SWS + 1);
-    SIGNAL up : STD_LOGIC := '1';
 BEGIN
 
-    -- Instantiate the PWM
+    -- Instantiate the PWM modules
     PWM : FOR i IN 1 TO TAIL_LENGTH GENERATE
     BEGIN
         PWM : PulseWidthModulator
         GENERIC MAP(
-            BIT_LENGTH => BIT_LENGTH,
+            BIT_LENGTH => BIT_LENGTH
-            T_ON_INIT => 64,
-            PERIOD_INIT => 128,
-            PWM_INIT => '0'
         )
         PORT MAP(
             reset => reset,
             clk => clk,
             Ton => STD_LOGIC_VECTOR(to_unsigned(i, BIT_LENGTH)),
             Period => STD_LOGIC_VECTOR(to_unsigned(TAIL_LENGTH - 1, BIT_LENGTH)),
-            PWM => leds_pwm(i - 1)
+            PWM => pwms(i - 1)
         );
     END GENERATE;
 
-    -- Sincronous logic
+    -- Synchronous logic for LED control
     PROCESS (clk, reset)
-        VARIABLE counter : UNSIGNED(46 DOWNTO 0) := (OTHERS => '0');
+        VARIABLE up : STD_LOGIC := '1'; -- Direction of LED movement
+        VARIABLE leds_sr : leds_sr_type := (OTHERS => 0); -- Shift register for LED positions
+        VARIABLE counter : UNSIGNED(46 DOWNTO 0) := (OTHERS => '0'); -- Timing counter
+        VARIABLE n_period : UNSIGNED(NUM_OF_SWS DOWNTO 0) := to_unsigned(1, NUM_OF_SWS + 1); -- Period multiplier
     BEGIN
         IF reset = '1' THEN
-            leds_sr <= (OTHERS => 0);
+            leds_sig <= (OTHERS => '0'); -- Turn off all LEDs
-            led_sig <= (OTHERS => '0');
+            leds_sr := (OTHERS => 0); -- Reset shift register
-            counter := (OTHERS => '0');
+            counter := (OTHERS => '0'); -- Reset counter
-            up <= '1';
+            up := '1'; -- Set initial direction
         ELSIF rising_edge(clk) THEN
+            -- Update period multiplier based on switches
+            n_period := unsigned('0' & sw) + 1;
 
-            -- Kitt logic: Update direction
+            -- Increment counter
-            IF leds_sr(TAIL_LENGTH - 1) = led'high THEN
-                up <= '0';
-            ELSIF leds_sr(TAIL_LENGTH - 1) = led'low THEN
-                up <= '1';
-            END IF;
-
-            -- Increment the counter
             counter := counter + to_unsigned(CLK_PERIOD_NS, counter'LENGTH);
 
-            -- Calculate the number of periods
+            -- Check if counter exceeds threshold
             IF counter >= (MIN_KITT_CAR_STEP_NS * n_period) THEN
+                -- Update direction
+                IF leds_sr(leds_sr'HIGH) = led'high THEN
+                    up := '0'; -- Change to backward
+                ELSIF leds_sr(leds_sr'HIGH) = led'low THEN
+                    up := '1'; -- Change to forward
+                END IF;
 
-                -- Reset led_sig
+                -- Shift LEDs based on direction
-                led_sig <= (OTHERS => '0');
-
-                -- Shift the leds
                 IF up = '1' THEN
-                    leds_sr <= (leds_sr(TAIL_LENGTH - 1) + 1) & leds_sr(TAIL_LENGTH - 1 DOWNTO 1);
+                    leds_sr := (leds_sr(leds_sr'HIGH) + 1) & leds_sr(leds_sr'HIGH DOWNTO 1);
                 ELSE
-                    leds_sr <= (leds_sr(TAIL_LENGTH - 1) - 1) & leds_sr(TAIL_LENGTH - 1 DOWNTO 1);
+                    leds_sr := (leds_sr(leds_sr'HIGH) - 1) & leds_sr(leds_sr'HIGH DOWNTO 1);
                 END IF;
 
-                -- Assign the LEDs
+                counter := (OTHERS => '0'); -- Reset counter
-                FOR i IN 0 TO TAIL_LENGTH - 1 LOOP
+            END IF;
-                    led_sig(leds_sr(i)) <= leds_pwm(i);
+
+            -- Assign PWM signals to LEDs
+            leds_sig <= (OTHERS => '0');
+            FOR i IN leds_sr'REVERSE_RANGE LOOP
+                leds_sig(leds_sr(i)) <= pwms(i);
             END LOOP;
-
-                -- Reset the counter
-                counter := (OTHERS => '0');
-            END IF;
         END IF;
     END PROCESS;
 
-    -- Handle the switch
+    -- Assign LED signals to output
-    PROCESS (sw)
+    led <= leds_sig;
-    BEGIN
-        n_period <= unsigned('0' & sw) + 1;
-    END PROCESS;
-
-    led <= led_sig;
 
 END Behavioral;

LAB1/src/PulseWidthModulator.vhd

@@ -33,10 +33,7 @@ use IEEE.NUMERIC_STD.ALL;
 
 entity PulseWidthModulator is
     Generic(
-        BIT_LENGTH  : INTEGER RANGE 1 to 16 := 8;
+        BIT_LENGTH  : INTEGER RANGE 1 to 16 := 8            
-        T_ON_INIT   : POSITIVE := 64;   
-        PERIOD_INIT : POSITIVE := 128;             
-        PWM_INIT    : STD_LOGIC := '0'
     );
     Port (
         reset   : IN STD_LOGIC;

LAB1/vivado/lab1_kit_car_pwm/lab1_kit_car_pwm.xpr

@@ -46,7 +46,7 @@
     <Option Name="IPUserFilesDir" Val="$PIPUSERFILESDIR"/>
     <Option Name="IPStaticSourceDir" Val="$PIPUSERFILESDIR/ipstatic"/>
     <Option Name="EnableBDX" Val="FALSE"/>
-    <Option Name="WTXSimLaunchSim" Val="0"/>
+    <Option Name="WTXSimLaunchSim" Val="26"/>
     <Option Name="WTModelSimLaunchSim" Val="0"/>
     <Option Name="WTQuestaLaunchSim" Val="0"/>
     <Option Name="WTIesLaunchSim" Val="0"/>
@@ -107,9 +107,15 @@
     </FileSet>
     <FileSet Name="sim_1" Type="SimulationSrcs" RelSrcDir="$PSRCDIR/sim_1" RelGenDir="$PGENDIR/sim_1">
       <Filter Type="Srcs"/>
+      <File Path="$PPRDIR/../../sim/tb_KittCarPWM.vhd">
+        <FileInfo>
+          <Attr Name="UsedIn" Val="synthesis"/>
+          <Attr Name="UsedIn" Val="simulation"/>
+        </FileInfo>
+      </File>
       <Config>
         <Option Name="DesignMode" Val="RTL"/>
-        <Option Name="TopModule" Val="KittCarPWM"/>
+        <Option Name="TopModule" Val="tb_KittCarPWM"/>
         <Option Name="TopLib" Val="xil_defaultlib"/>
         <Option Name="TopAutoSet" Val="TRUE"/>
         <Option Name="TransportPathDelay" Val="0"/>