diff --git a/examples/pwm/pwm.go b/examples/pwm/pwm.go
index 00549a2..215803e 100644
--- a/examples/pwm/pwm.go
+++ b/examples/pwm/pwm.go
@@ -1,6 +1,6 @@
 /*
 
-A PWM example by @Drahoslav7, using the go-rpio library 
+A PWM example by @Drahoslav7, using the go-rpio library
 
 Toggles a LED on physical pin 19 (mcu pin 10)
 Connect a LED with resistor from pin 19 to ground.
@@ -24,15 +24,18 @@ func main() {
 
         pin := rpio.Pin(19)
         pin.Mode(rpio.Pwm)
-        pin.Freq(60000)
+        pin.Freq(64000)
         pin.DutyCycle(0, 32)
+        // the LED will be blinking at 2000Hz
+        // (source frequency divided by cycle length => 64000/32 = 2000)
 
+        // five times smoothly fade in and out
         for i := 0; i < 5; i++ {
                 for i := uint32(0); i < 32; i++ { // increasing brightness
                         pin.DutyCycle(i, 32)
                         time.Sleep(time.Second/32)
                 }
-                for i := uint32(32); i != 0; i-- { // decreasing brightness
+                for i := uint32(32); i > 0; i-- { // decreasing brightness
                         pin.DutyCycle(i, 32)
                         time.Sleep(time.Second/32)
                 }