Output PWM on any pin. Partly based on SoftPWM with some improvements

Files at this revision

API Documentation at this revision

Comitter:
gagarcr
Date:
Thu Sep 03 08:15:34 2015 +0000
Commit message:
Intial version based on SoftPWM

Changed in this revision

SoftPwmOut.cpp Show annotated file Show diff for this revision Revisions of this file
SoftPwmOut.h Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r 813ee8141cdd SoftPwmOut.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SoftPwmOut.cpp	Thu Sep 03 08:15:34 2015 +0000
@@ -0,0 +1,83 @@
+#include "mbed.h"
+#include "InterruptIn.h"
+#include "SoftPwmOut.h"
+
+SoftPwmOut::SoftPwmOut(PinName pin) : _outPin(pin) // Constructor definition. Assign _out
+{
+    _interval = 0.1; // Default fequency
+    _width = 0;
+    start(); 
+}
+
+float SoftPwmOut::read()
+{
+    return _width / _interval;    
+}
+
+void SoftPwmOut::write(float duty)
+{
+    _width = _interval * duty;
+    if ( duty <= 0.0 ) _width =  0.0;
+    if ( duty > 1.0 )  _width =  _interval;
+}
+
+void SoftPwmOut::start()
+{
+    _ticker.attach(this,&SoftPwmOut::TickerInterrupt,_interval);
+}
+
+void SoftPwmOut::stop()
+{
+    _ticker.detach();
+    //wait(width);
+}
+
+void SoftPwmOut::period(float period)
+{
+    _interval = period;
+    start();
+}
+
+void SoftPwmOut::period_ms(int period)
+{
+    SoftPwmOut::period((float)period / 1000);
+    start();
+}
+
+void SoftPwmOut::period_us(int period)
+{
+    SoftPwmOut::period((float)period / 1000000);
+    start();
+}
+
+void SoftPwmOut::pulsewidth(float width)
+{
+   _width = width;
+   if ( _width < 0.0 ) _width = 0.0;
+   if ( _width > _interval) _width = _interval;
+}
+
+void SoftPwmOut::pulsewidth_ms(int width)
+{
+    SoftPwmOut::pulsewidth((float)width / 1000);
+}
+
+void SoftPwmOut::pulsewidth_us(int width)
+{
+    SoftPwmOut::pulsewidth((float)width / 1000000);
+}
+
+void SoftPwmOut::TickerInterrupt()
+{
+    _outPin = 0;
+    if ( _width <= 0 ) return;
+    _timeout.attach(this,&SoftPwmOut::end,_width);   
+}
+
+void SoftPwmOut::end()
+{  
+    _outPin = 1;
+//    _timeout.detach();
+}
+;
+
diff -r 000000000000 -r 813ee8141cdd SoftPwmOut.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SoftPwmOut.h	Thu Sep 03 08:15:34 2015 +0000
@@ -0,0 +1,45 @@
+#ifndef SoftPWM_H
+#define SoftPWM_H
+#define POSITIVE true
+#define NEGATIVE false
+
+#include "mbed.h"
+
+class SoftPwmOut  
+{
+public:
+    SoftPwmOut(PinName); 
+//    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;
+    }
+    SoftPwmOut& operator=(float duty)  {
+        _width = _interval * duty;
+        if ( duty <= 0.0 ) _width =  0.0;
+        if ( duty > 1.0 )  _width =  _interval;
+        return *this;
+    }
+    
+private:
+    Timeout _timeout;
+    Ticker _ticker;
+    void TickerInterrupt();
+    void end();
+    DigitalOut _outPin;
+    float _width;
+    float _interval;
+                
+};
+#endif
\ No newline at end of file