@@ -106,4 +106,9 @@ Signal--+------|PD0 |
GND------------|GND |
`------'
R: 1K Ohm resistor
-```
+```
+
+## Arduino Micro with ATMega32U4
+Note that Arduino Micro PCB marking is different from real AVR port name. D0 of Arduino Micro is not PD0, PD0 is D3. Check schematic yourself.
+http://arduino.cc/en/uploads/Main/arduino-micro-schematic.pdf