syouichi imamori / SoftPWM

The PWM output by software. Can be output to any pin. It can be used to replace the Pwmout.

Dependents:   SoftPWM_Example XYZ_Joystick_PWM mbed_pwm mbed_Ahan_robocon ... more 

#include "mbed.h"
#include "math.h"
#include "SoftPWM.h"

SoftPWM led[] = { LED1,LED2,LED3,LED4 };

int main()
{
    for ( int i=0; i<4; i++ ) led[i].period_ms( 1 );
    while (1)   {
        for ( int j=0; j<360; j+=10 ) {
            for ( int k=0; k<4; k++ ) {
                led[k] = cos( (j+k*90)*2.0*3.14/360 ) * 0.5 + 0.5;
                wait(0.01);
            }
        }
    }
}

Diff: SoftPWM.h

Revision:
0:7918ce37626c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SoftPWM.h	Wed Oct 23 19:31:14 2013 +0000
@@ -0,0 +1,45 @@
+#ifndef SoftPWM_H
+#define SoftPWM_H
+#define POSITIVE true
+#define NEGATIVE false
+
+#include "mbed.h"
+
+class SoftPWM  
+{
+private:
+    Timeout _timeout;
+    Ticker _ticker;
+    void end();
+    DigitalOut pulse;
+    bool positive;
+    void TickerInterrapt();
+    float width;
+    float interval;
+public:
+    SoftPWM(PinName,bool mode=true); 
+//    void attach_us(int);
+    void start();
+    void write(float);
+    float read();
+    void pulsewidth(float);
+    void pulsewidth_ms(int);
+    void pulsewidth_us(int);
+    void period(float);
+    void period_ms(int);
+    void period_us(int);
+    void stop();
+    operator float()  { 
+        if ( width <= 0.0 ) return 0.0;
+        if ( width > 1.0 )  return 1.0;
+        return width / interval;
+    }
+    SoftPWM& operator=(float duty)  {
+        width = interval * duty;
+        if ( duty <= 0.0 ) width =  0.0;
+        if ( duty > 1.0 )  width =  interval;
+        return *this;
+    }
+                
+};
+#endif
\ No newline at end of file