Tetsuya Hoshino / RotaryEncoder

ロータリーエンコーダー (機械接点式インクリメンタル型) の信号をデコードするクラスです。 Rotary Encoder (incremental, mechanical switch type) signal decoder class.

Diff: RotaryEncoder.cpp

Revision:
0:fcf360069f17
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/RotaryEncoder.cpp	Sun Sep 07 23:31:47 2014 +0000
@@ -0,0 +1,26 @@
+#include <RotaryEncoder.h>
+
+RotaryEncoder::RotaryEncoder(PinName A, PinName B)
+ : terminalA(A, PullUp), terminalB(B, PullUp) 
+{
+}
+
+void RotaryEncoder::attach(void (*callback)(int)) {
+    callbackFunc = callback;
+    tick.attach_us(this, &RotaryEncoder::smpling, RotaryEncoder_SamplingInterval);
+}
+
+void RotaryEncoder::detach() {
+    tick.detach();
+}
+
+void RotaryEncoder::smpling() {
+    static uint8_t val  = 0xFF;
+    uint8_t now = (terminalA.read() << 1) | (terminalB.read());
+    if (now == (val & 0x03)) return;
+    val = (val << 2) | now;
+    switch (val) {
+        case 0x4B: (*callbackFunc)(1); break; // cw  : 0b01001011 = 0x4B
+        case 0x87: (*callbackFunc)(0); break; // ccw : 0b10000111 = 0x87
+    }
+}