Revision 0:db7f371c8530, committed 2016-07-20

Comitter:

Sateg

Date:

Wed Jul 20 00:30:23 2016 +0000

Commit message:

Working, conservative rotary encoder handler.

Changed in this revision

diff -r 000000000000 -r db7f371c8530 RotaryEncoder.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/RotaryEncoder.cpp	Wed Jul 20 00:30:23 2016 +0000
@@ -0,0 +1,45 @@
+#include "RotaryEncoder.h"
+
+RotaryEncoder::RotaryEncoder(void (*cb)(void), PinName channelA_, PinName channelB_, PinName pushPin_, float period)
+ : channelA(channelA_), channelB(channelB_), pushPin(pushPin_)
+{
+    direction = 0;
+    counter = 0;
+    lastDirection = 0;
+
+    encoderTicker.attach(this, &RotaryEncoder::pulse, period);
+    pushPin.rise(cb);
+}
+
+RotaryEncoder::~RotaryEncoder() {};
+
+/** Public methods **/
+
+int8_t RotaryEncoder::getDirection() const
+{
+    return direction;   
+}
+
+int RotaryEncoder::getCounter() const
+{
+    return counter;
+}
+
+bool RotaryEncoder::getPushButton() const
+{
+    return false;   
+}
+
+/** Private methods **/
+
+void RotaryEncoder::pulse()
+{    
+    lastDirection <<= 2;
+    if (channelB) lastDirection |= 1;
+    if (channelA) lastDirection |= 2;
+    
+    direction = encoderTable[lastDirection & 0x0F];
+    counter += direction;
+}
+
+const int8_t RotaryEncoder::encoderTable[] = {0, 0, 0, 0, 1, 0, 0, -1, -1, 0, 0, 1, 0, 0, 0, 0};
\ No newline at end of file

diff -r 000000000000 -r db7f371c8530 RotaryEncoder.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/RotaryEncoder.h	Wed Jul 20 00:30:23 2016 +0000
@@ -0,0 +1,40 @@
+#include "mbed.h"
+
+#ifndef ROTARY_ENCODER_H_
+#define ROTARY_ENCODER_H_
+
+/**
+ Rotary encoder handling class.
+ Starts a ticker which checks the status of the encoder and
+ sets the rotation directions based on its status.
+*/
+class RotaryEncoder {
+public:
+    RotaryEncoder(void (*cb)(void), PinName channelA_, PinName channelB_, PinName pushPin_, float period = 0.01);
+    virtual ~RotaryEncoder();
+    
+    /// Retrieve rotation direction.
+    int8_t getDirection() const;
+    /// Retrieve push button status.
+    bool getPushButton() const;
+    /// Launched by Ticker to determine rotation direction
+    void pulse();
+    
+    int getCounter() const;
+    
+    private:
+    
+    /// Table which helps determine the rotation direction
+    static const int8_t encoderTable[];
+
+    int counter;
+    int8_t direction;
+    int8_t lastDirection;
+    InterruptIn channelA;
+    InterruptIn channelB;
+    InterruptIn pushPin;
+    Ticker encoderTicker;
+    
+};
+
+#endif /* ROTARY_ENCODER_H_ */
\ No newline at end of file