Revision 0:c90b36abcbf8, committed 2013-09-25

Comitter:

vsluiter

Date:

Wed Sep 25 14:55:08 2013 +0000

Child:

1:2dd7853c911a

Commit message:

Initial Commit

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/encoder.cpp	Wed Sep 25 14:55:08 2013 +0000
@@ -0,0 +1,68 @@
+
+#include "encoder.h"
+
+Encoder::Encoder(PinName int_a, PinName int_b) : pin_a(int_a), pin_b(int_b)
+{
+    EncoderTimer.start();
+    pin_a.fall(this,&Encoder::encoderFalling);
+    pin_a.rise(this,&Encoder::encoderRising);
+    m_position = 0;
+    m_speed = 0;
+    zero_speed = false;
+}
+ 
+void Encoder::encoderFalling(void)
+{
+    //temporary speed storage, in case higher interrupt level does stuff
+    float temp_speed;
+    int motortime_now = EncoderTimer.read_us();
+    EncoderTimer.reset();
+    EncoderTimeout.attach(this,&Encoder::timeouthandler,0.1);
+    /*calculate as ticks per second*/
+    if(zero_speed)
+        temp_speed  = 0;
+    else
+        temp_speed = 1000000./motortime_now;
+    zero_speed = false;
+    if(pin_b)
+    {
+        m_position++;
+        m_speed = temp_speed;
+    }
+    else
+    {
+        m_position--;    
+        m_speed  = -temp_speed; //negative speed
+    }
+}
+
+void Encoder::encoderRising(void)
+{
+    //temporary speed storage, in case higher interrupt level does stuff
+    float temp_speed;
+    int motortime_now = EncoderTimer.read_us();
+    EncoderTimer.reset();
+    EncoderTimeout.attach(this,&Encoder::encoderFalling,0.1);
+    /*calculate as ticks per second*/
+    if(zero_speed)
+        temp_speed  = 0;
+    else
+        temp_speed = 1000000./motortime_now;
+    zero_speed = false;
+    if(pin_b)
+    {
+        m_position--;
+        m_speed = -temp_speed; //negative speed
+    }
+    else
+    {
+        m_position++;    
+        m_speed  = temp_speed; 
+    }
+}
+
+void Encoder::timeouthandler(void)
+{
+    m_speed  = 0;
+    zero_speed = true;
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/encoder.h	Wed Sep 25 14:55:08 2013 +0000
@@ -0,0 +1,27 @@
+#ifndef _ENCODER_H_
+#define _ENCODER_H_
+
+#include "mbed.h"
+
+class Encoder
+{
+    public:
+    Encoder(PinName int_a, PinName int_b);
+    int32_t getPosition(){return m_position;}
+    void    setPosition(int32_t pos){m_position = pos;}
+    float   getSpeed(){return m_speed;}
+    private:
+    void encoderFalling(void);
+    void encoderRising(void);
+    Timer EncoderTimer;
+    Timeout EncoderTimeout;
+    InterruptIn pin_a;
+    DigitalIn pin_b;
+    int32_t m_position;
+    float   m_speed;
+    void timeouthandler(void);
+    bool zero_speed;
+};
+
+
+#endif //_ENCODER_H_
\ No newline at end of file