Diff: RPG.cpp

Revision:

2:94d27805abda

Parent:

0:4a7e5f6a59a4

Child:

3:e041653b7338

diff -r 0b389c2c21b5 -r 94d27805abda RPG.cpp
--- a/RPG.cpp	Fri Oct 12 14:04:17 2012 +0000
+++ b/RPG.cpp	Sun May 21 09:59:35 2017 +0000
@@ -1,8 +1,9 @@
 /**
 * =============================================================================
-* Rotary Pulse Generator class (Version 0.0.1)
+* Rotary Pulse Generator class (Version 1.0.0)
 * =============================================================================
 * Copyright (c) 2012 Christopher Anderson
+* Copyright (c) 2017 Dmitry Makarenko
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
@@ -31,23 +32,30 @@
  * Constructor(Channel A input pin, Channel B input pin, Pushbutton input pin)
  */
 RPG::RPG(PinName pA, PinName pB, PinName pPB)
-    : chRPG(pA, pB), PB(pPB)
+    : IA(pA), B(pB), PB(pPB), m_dir(0)
     {
-        chRPG.input();
-        chRPG.mode(PullUp);
+        IA.mode(PullUp);
+        IA.fall(this, &RPG::onA);
+        B.mode(PullUp);
         PB.mode(PullUp);
         wait_us(10);
-        RPGO = chRPG;
     }
     
-/**
- *Destructor
+/** 
+ * Interrupt handler for channel A.
+ * Increments or decrements m_dir depending on channel B state.
  */
-RPG::~RPG()
-{}
+void RPG::onA() {
+    if(B == 1) {
+        m_dir ++;
+    }
+    else {
+        m_dir --;
+    }
+}
 
 /**
- *reads and debounces push button returns bool result
+ * Reads and debounces push button returns bool result
  */
 bool RPG::pb()
 {
@@ -61,23 +69,14 @@
 }
 
 /**
- *Determines direction of rotation returns:
- *1 for clockwise
- *-1 for counter-clockwise
- *0 for no rotation
+ * Direction and amount of rotation since last read:
+ * +1 for clockwise
+ * -1 for counter-clockwise
+ * 0 for no rotation
  */
 int RPG::dir()
 {
-    int dir = 0;
-    RPGO = chRPG;
-    wait(.005);
-    RPGN = chRPG;
-    if(RPGN != RPGO)
-    {
-        if((RPGN & 1) != (RPGO >> 1)) dir = 1;
-        else dir = -1;
-    }
-    else dir = 0;
-    RPGO = RPGN;
-    return dir;
+    int tmp = m_dir;
+    m_dir = 0;
+    return tmp;
 }
\ No newline at end of file