Diff: RotaryEncode.cpp

Revision:

0:498b9b4a7bb9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/RotaryEncode.cpp	Tue Mar 02 08:27:23 2010 +0000
@@ -0,0 +1,81 @@
+/*
+RotaryEncode
+(c) 2009, cstyles
+*/
+
+#include "RotaryEncode.h"
+#include "mbed.h"
+
+/*
+ Constructor, pin names for I2C and the I2C addrss of the device
+ */
+
+
+RotaryEncode::RotaryEncode(PinName A, PinName B) 
+  : _rotary_in(A,B) {    
+
+    _position = 0;
+    
+    // Attach ticker
+    _ticker.attach(this, &RotaryEncode::_ticker_handler, 0.010);       
+}
+
+
+
+int RotaryEncode::read(void) {
+   int rval = _position;
+   _position = 0;
+   return (rval);
+}
+
+
+
+
+void RotaryEncode::_ticker_handler(void) {
+
+    _state = _rotary_in;
+    _e = R_W;
+
+    // we're in the no-change state
+    if (_state == 0x03) {
+        return;
+    }
+
+    while (_state != 0x03) {
+    switch (_e) {
+        case R_W:
+            if (_state == 0x02)
+                _e = R_R1;
+            else if (_state == 0x01)
+                _e = R_L1;
+            break;
+
+        case R_L1:
+            if (_state == 0x00)
+                _e = R_R2;
+            break;
+        case R_L2:
+            if (_state == 0x01) {
+                _e = R_R3;
+                _position++;
+            }
+            break;
+        case R_R1:
+            if (_state == 0x00)
+                _e = R_L2;
+            break;
+        case R_R2:
+            if (_state == 0x02) {
+                _e = R_L3;
+                _position--;
+            }
+            break;
+        }
+    _state = _rotary_in;
+    }
+    
+}
+
+
+
+