Merge pull request #1 from uChip/master

Added example compatible with Atmega32U4

examples/Interrupt/InterruptProMicro.ino

@@ -0,0 +1,49 @@
+/*
+    Rotary Encoder - Interrupt Example 
+    This is the same as "Interrupt.ino" but works
+    the Pro Micro from Sparkfun which uses the 
+    Atmega32U4 microcontroller.  This controller
+    does not have the PCIE2 or PCMSK2 registers used in the
+    Interrupt example.  Instead these are moved
+    to the PCIE0 and PCMSK0 registers instead.
+
+    These registers support interrupts on Pro Micro
+    pins 8, 9, 10 or 11.  This example wires the encoder
+    to pins 8 and 9.
+
+    Note that the interrupt vector also changes to
+    correspond to the PCIE0 interrupt.
+    
+    The circuit:
+    * encoder pin A to Arduino pin 8
+    * encoder pin B to Arduino pin 9
+    * encoder ground pin to ground (GND)
+*/
+
+#include <Rotary.h>
+
+Rotary r = Rotary(8, 9);
+
+void setup() {
+  Serial.begin(9600);
+  PCICR |= (1 << PCIE0);
+  PCMSK0 |= (1 << PCINT4) | (1 << PCINT5);
+  sei();
+}
+
+void loop() {
+
+}
+
+ISR(PCINT0_vect) {
+  unsigned char result = r.process();
+  if (result == DIR_NONE) {
+    // do nothing
+  }
+  else if (result == DIR_CW) {
+    Serial.println("ClockWise");
+  }
+  else if (result == DIR_CCW) {
+    Serial.println("CounterClockWise");
+  }
+}