library encoder

Dependents:   Project_Plum OnMotor DataMotor bacaencoder

Files at this revision

API Documentation at this revision

Comitter:
yafieabdillah
Date:
Sun Feb 03 15:51:54 2019 +0000
Commit message:
ghgy

Changed in this revision

encoderKRAI.cpp Show annotated file Show diff for this revision Revisions of this file
encoderKRAI.h Show annotated file Show diff for this revision Revisions of this file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/encoderKRAI.cpp	Sun Feb 03 15:51:54 2019 +0000
@@ -0,0 +1,126 @@
+/********************************************************/
+/*          Library untuk pembacaan Encoder             */
+/*                  Adapsi dari QEI                     */
+/*                                                      */
+/*  Encoder yang sudah dicoba :                         */
+/*  1. Autonics                                         */
+/*  2. Encoder bawaan Motor                             */
+/*                                                      */
+/*  ______________________                              */
+/*  |______Autonics______|                              */
+/*  | Out A = Input 1    |                              */
+/*  | Out B = Input 2    |                              */
+/*  | 5V                 |                              */
+/*  |_Gnd________________|                              */
+/*                                                      */
+/********************************************************/
+
+#include "mbed.h"
+
+#include "encoderKRAI.h"
+
+encoderKRAI::encoderKRAI(PinName channelA,
+                         PinName channelB,
+                         int pulsesPerRev,
+                         Encoding encoding) : channelA_(channelA), channelB_(channelB)
+{
+    pulses_       = 0;
+    revolutions_  = 0;
+    pulsesPerRev_ = pulsesPerRev;
+    encoding_     = encoding;
+
+    //Workout what the current state is.
+    int chanA = channelA_.read();
+    int chanB = channelB_.read();
+
+    //2-bit state.
+    currState_ = (chanA << 1) | (chanB);
+    prevState_ = currState_;
+
+    //X2 encoding uses interrupts on only channel A.
+    //X4 encoding uses interrupts on      channel A,
+    //and on channel B.
+    channelA_.rise(this, &encoderKRAI::encode);
+    channelA_.fall(this, &encoderKRAI::encode);
+
+    //If we're using X4 encoding, then attach interrupts to channel B too.
+    if (encoding == X4_ENCODING) {
+        channelB_.rise(this, &encoderKRAI::encode);
+        channelB_.fall(this, &encoderKRAI::encode);
+    }
+}
+
+void encoderKRAI::reset(void) {
+
+    pulses_      = 0;
+    revolutions_ = 0;
+
+}
+
+/*int encoderKRAI::getCurrentState(void) {
+
+    return currState_;
+
+}*/
+
+int encoderKRAI::getPulses(void) {
+
+    return pulses_;
+
+}
+
+int encoderKRAI::getRevolutions(void) {
+
+    revolutions_ = pulses_ / pulsesPerRev_;
+    return revolutions_;
+
+}
+
+////////////////////////////////////////////////////////
+
+void encoderKRAI::encode(void) {
+
+    int change = 0;
+    int chanA  = channelA_.read();
+    int chanB  = channelB_.read();
+
+    //2-bit state.
+    currState_ = (chanA << 1) | (chanB);
+
+    if (encoding_ == X2_ENCODING) {
+
+        //11->00->11->00 is counter clockwise rotation or "forward".
+        if ((prevState_ == 0x3 && currState_ == 0x0) ||
+                (prevState_ == 0x0 && currState_ == 0x3)) {
+
+            pulses_++;
+
+        }
+        //10->01->10->01 is clockwise rotation or "backward".
+        else if ((prevState_ == 0x2 && currState_ == 0x1) ||
+                 (prevState_ == 0x1 && currState_ == 0x2)) {
+
+            pulses_--;
+
+        }
+
+    } else if (encoding_ == X4_ENCODING) {
+
+        //Entered a new valid state.
+        if (((currState_ ^ prevState_) != INVALID) && (currState_ != prevState_)) {
+            //2 bit state. Right hand bit of prev XOR left hand bit of current
+            //gives 0 if clockwise rotation and 1 if counter clockwise rotation.
+            change = (prevState_ & PREV_MASK) ^ ((currState_ & CURR_MASK) >> 1);
+
+            if (change == 0) {
+                change = -1;
+            }
+
+            pulses_ -= change;
+        }
+
+    }
+
+    prevState_ = currState_;
+
+}
\ No newline at end of file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/encoderKRAI.h	Sun Feb 03 15:51:54 2019 +0000
@@ -0,0 +1,106 @@
+#ifndef ENCODERKRAI_H
+#define ENCODERKRAI_H
+
+/**
+ * Includes
+ */
+#include "mbed.h"
+
+/**
+ * Defines
+ */
+#define PREV_MASK 0x1 //Mask for the previous state in determining direction
+//of rotation.
+#define CURR_MASK 0x2 //Mask for the current state in determining direction
+//of rotation.
+#define INVALID   0x3 //XORing two states where both bits have changed.
+
+/**
+ * Quadrature Encoder Interface.
+ */
+class encoderKRAI {
+
+public:
+
+    typedef enum Encoding {
+
+        X2_ENCODING,
+        X4_ENCODING
+
+    } Encoding;
+    
+    /** Membuat interface dari encoder    
+     *
+     * @param inA DigitalIn, out A dari encoder
+     * @param inB DigitalIn, out B dari encoder
+     */
+    encoderKRAI(PinName channelA, PinName channelB, int pulsesPerRev, Encoding encoding = X2_ENCODING);
+    
+    /**
+     * Reset encoder.
+     *
+     * Menset pulse dan revolusi/putaran menjadi 0
+     */
+    void reset(void);
+    
+    /**
+     * Membaca pulse yang didapat oleh encoder
+     *
+     * @return Nilai pulse yang telah dilalui.
+     */
+    int getPulses(void);
+    
+    /**
+     * Membaca putaran yang didapat oleh encoder
+     *
+     * @return Nilai revolusi/putaran yang telah dilalui.
+     */
+    int getRevolutions(void);
+    
+    /**
+     * Membaca pulse yang didapat oleh encoder
+     *
+     * @return Nilai pulse yang telah dilalui.
+     */
+    //int readDeltaPulses(void);
+    
+    /**
+     * Membaca putaran yang didapat oleh encoder
+     *
+     * @return Nilai revolusi/putaran yang telah dilalui.
+     */
+    //int readDeltaRevolutions(void);
+
+private:
+
+    /**
+     * Menghitung pulse
+     *
+     * Digunakan setiap rising/falling edge baik channel A atau B
+     * Membaca putaran CW atau CCW => mengakibatkan pertambahan/pengurangan pulse
+     */
+    void encode(void);
+
+    /**
+     * Indeks setiap rising edge untuk menghitung putaran
+     * Nilai bertambah 1
+     */
+    //void index(void);
+
+    Encoding encoding_;
+
+    InterruptIn channelA_;
+    InterruptIn channelB_;
+    //InterruptIn index_;
+
+    int          pulsesPerRev_;
+    int          prevState_;
+    int          currState_;
+
+    volatile int pulses_;
+    volatile int revolutions_;
+
+
+};
+
+#endif /* ENCODERKRAI_H */
\ No newline at end of file