Fix incorrect oen pin in HW PWM controller

hw_pwm_controller/src/top.v

@@ -3,7 +3,7 @@
 module top (
 	input clk,
 	input [0:0] btn,
-	input [7:0] sw,
+	input [11:0] sw,
 	output [2:0] RGB_led_A,
 	output [7:0] led
 );
@@ -19,6 +19,9 @@ conf_div clock_div (
 
 wire clk_cur = btn[0] ? clk2 : clk;
 
+wire oen = sw[11];
+assign led[0] = oen;
+
 pwm_core #(
 	.WINDOW_REG_SIZE(8)
 ) pwm_core_r (
@@ -26,7 +29,7 @@ pwm_core #(
 	.rst(0),
 	.duty(sw[7:0]),
 	.window_width(255),
-	.oen(sw[11]),
+	.oen(oen),
 	.pulse(RGB_led_A[0])
 );