Diff: main.cpp

Revision:

3:03bf4cc245ce

Parent:

2:d5ecbd5f9886

Child:

4:79eee74e1bbd

--- a/main.cpp	Wed Jan 31 21:15:53 2018 +0000
+++ b/main.cpp	Wed Jan 31 21:48:21 2018 +0000
@@ -4,9 +4,11 @@
 
   EXAMPLE DESCRIPTION
 
-  Sets PWM out on pin PA_8 with f=2 Hz and duty cycle = 0.5. The best use is to 
-  connect LED to pin PA_8 (using wiring with transitor) to see effect of PWM.
-  
+  Sets PWM out on pin PA_8 with f=200 Hz. Then changes duty cycle from 0 to 1
+  in 500 steps with 4 ms wait (from 0 to 1 in 1 s) and back from 1 to 0. 
+  The best use is to connect LED to pin PA_8 (using wiring with transitor) 
+  to see effect of PWM.
+   
 *******************************************************************************/
 
 PwmOut PWM(PA_8); // definition of PWM pin
@@ -14,18 +16,18 @@
 int main()
 {
 
-    PWM.period_ms(5); // period of PWM - f=1/T -> f=1/0.005=200 Hz
+    PWM.period_ms(5); // period of PWM - f=1/T -> f=1/0.005=4200 Hz
     PWM.pulsewidth_us(0); // duration of active pulse
                             //sets duty cycle - duty cycle = pulsewidth/period
 
     while(1) {
         for(int i=0;i<=5000;i=i+10){
-            PWM.pulsewidth_us(i);
-            wait_ms(1000);
+            PWM.pulsewidth_us(i); // increment duty cycle
+            wait_ms(4); // wait 4 ms (whole for takes 1 s)
         }
         for(int i=5000;i>=0;i=i-10){
-            PWM.pulsewidth_us(i);
-            wait_ms(1000);
+            PWM.pulsewidth_us(i); // decrement duty cycle
+            wait_ms(4); // wait 4 ms (whole for takes 1 s)
         }
     }
 }