diff --git a/hardware/arduino/cores/arduino/Arduino.h b/hardware/arduino/cores/arduino/Arduino.h
index 830c9952f..b26582589 100755
--- a/hardware/arduino/cores/arduino/Arduino.h
+++ b/hardware/arduino/cores/arduino/Arduino.h
@@ -46,7 +46,7 @@ extern "C"{
 #define EXTERNAL 1
 #define INTERNAL 2
 #else  
-#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__) || defined(__AVR_ATmega1284P__) 
+#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__) || defined(__AVR_ATmega1284P__) || defined(__AVR_ATmega644P__)
 #define INTERNAL1V1 2
 #define INTERNAL2V56 3
 #else
diff --git a/hardware/arduino/cores/arduino/wiring_analog.c b/hardware/arduino/cores/arduino/wiring_analog.c
index 0e9881f6a..23b01c65a 100644
--- a/hardware/arduino/cores/arduino/wiring_analog.c
+++ b/hardware/arduino/cores/arduino/wiring_analog.c
@@ -45,7 +45,7 @@ int analogRead(uint8_t pin)
 	if (pin >= 54) pin -= 54; // allow for channel or pin numbers
 #elif defined(__AVR_ATmega32U4__)
 	if (pin >= 18) pin -= 18; // allow for channel or pin numbers
-#elif defined(__AVR_ATmega1284__)
+#elif defined(__AVR_ATmega1284P__) || defined(__AVR_ATmega644P__)
 	if (pin >= 24) pin -= 24; // allow for channel or pin numbers
 #else
 	if (pin >= 14) pin -= 14; // allow for channel or pin numbers
diff --git a/hardware/arduino/cores/arduino/wiring_private.h b/hardware/arduino/cores/arduino/wiring_private.h
index 026ce1a01..f67826567 100755
--- a/hardware/arduino/cores/arduino/wiring_private.h
+++ b/hardware/arduino/cores/arduino/wiring_private.h
@@ -54,7 +54,7 @@ extern "C"{
 
 #if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
 #define EXTERNAL_NUM_INTERRUPTS 8
-#elif defined(__AVR_ATmega1284P__) 
+#elif defined(__AVR_ATmega1284P__) || defined(__AVR_ATmega644P__)
 #define EXTERNAL_NUM_INTERRUPTS 3
 #elif defined(__AVR_ATmega32U4__)
 #define EXTERNAL_NUM_INTERRUPTS 4