Diff: main.cpp

Revision:

0:30dcc43db185

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Oct 25 12:50:06 2018 +0000
@@ -0,0 +1,51 @@
+#include "mbed.h"
+
+
+#ifndef M_PI 
+#define M_PI 3.14159265358979323846 
+#endif 
+
+DigitalOut myled(LED1); 
+PwmOut CH1(PA_8); 
+PwmOut CH2(PA_15); 
+PwmOut CH3(PA_6);
+
+// dc : duty cycle
+// n:   sample 
+// f:   
+ 
+ /* This program calculates values of a sine 
+ function and splits them up in 100 points, these points are then written
+  to the duty cycle of the pwm signals.
+*/
+Ticker interrupt;
+InterruptIn button(USER_BUTTON);
+int n;
+double dc_min = 0.0, dc_max = 1.0;
+void sine_dc() { 
+    double dc, sine_term; 
+    n = n + 1;
+    if(n == 100) n = 0;
+    sine_term = (1 + sin(2*M_PI*n/100.0));
+    dc = sine_term * dc_min + (2 - sine_term) * dc_max;
+    CH1.write(dc/2);
+    CH2.write(dc/2);
+    CH3.write(dc/2);
+}
+int main() {
+    int f = 20000;
+    n = 0;
+    CH1.period_us(100);
+    CH1.write(0.5);
+    CH2.period_us(100);
+    CH2.write(0.5);
+    CH3.period_us(100);
+    CH3.write(0.5);
+    interrupt.attach_us(&sine_dc, f);
+    
+    while(1) {
+         myled = !myled;
+         wait(1);
+    }
+}
+