syouichi imamori
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);
}
}
}
}
Revision 0:7918ce37626c, committed 2013-10-23
- Comitter:
- komaida424
- Date:
- Wed Oct 23 19:31:14 2013 +0000
- Commit message:
- The PWM output by software. Can be output to any pin. It can be used to replace the Pwmout.
;
Changed in this revision
| SoftPWM.cpp | Show annotated file Show diff for this revision Revisions of this file |
| SoftPWM.h | Show annotated file Show diff for this revision Revisions of this file |
diff -r 000000000000 -r 7918ce37626c SoftPWM.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/SoftPWM.cpp Wed Oct 23 19:31:14 2013 +0000
@@ -0,0 +1,99 @@
+#include "mbed.h"
+#include "InterruptIn.h"
+#include "SoftPWM.h"
+
+SoftPWM::SoftPWM(PinName _outpin,bool _positive) : pulse(_outpin) //constructa
+{
+ if ( _positive )
+ pulse = 0;
+ else
+ pulse = 1;
+ positive = _positive;
+ interval = 0.02;
+ width = 0;
+ start();
+}
+
+float SoftPWM::read()
+{
+ if ( width <= 0.0 ) return 0.0;
+ if ( width > 1.0 ) return 1.0;
+ return width / interval;
+}
+
+void SoftPWM::write(float duty)
+{
+ width = interval * duty;
+ if ( duty <= 0.0 ) width = 0.0;
+ if ( duty > 1.0 ) width = interval;
+}
+
+void SoftPWM::start()
+{
+ _ticker.attach(this,&SoftPWM::TickerInterrapt,interval);
+}
+
+void SoftPWM::stop()
+{
+ _ticker.detach();
+ if ( positive )
+ pulse = 0;
+ else
+ pulse = 1;
+ wait(width);
+}
+
+void SoftPWM::period(float _period)
+{
+ interval = _period;
+ start();
+}
+
+void SoftPWM::period_ms(int _period)
+{
+ period((float)_period / 1000);
+ start();
+}
+
+void SoftPWM::period_us(int _period)
+{
+ period((float)_period / 1000000);
+ start();
+}
+
+void SoftPWM::pulsewidth(float _width)
+{
+ width = _width;
+ if ( width < 0.0 ) width = 0.0;
+}
+
+void SoftPWM::pulsewidth_ms(int _width)
+{
+ pulsewidth((float)_width / 1000);
+}
+
+void SoftPWM::pulsewidth_us(int _width)
+{
+ pulsewidth((float)_width / 1000000);
+}
+
+void SoftPWM::TickerInterrapt()
+{
+ if ( width <= 0 ) return;
+ _timeout.attach(this,&SoftPWM::end,width);
+ if ( positive )
+ pulse = 1;
+ else
+ pulse = 0;
+}
+
+void SoftPWM::end()
+{
+ if ( positive )
+ pulse = 0;
+ else
+ pulse = 1;
+// _timeout.detach();
+}
+;
+
diff -r 000000000000 -r 7918ce37626c SoftPWM.h
--- /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