diff --git a/atmel_start_config.atstart b/atmel_start_config.atstart
index 228d17e..2db4fac 100644
--- a/atmel_start_config.atstart
+++ b/atmel_start_config.atstart
@@ -108,7 +108,14 @@ drivers:
       eic_arch_wakeupen7: false
       eic_arch_wakeupen8: false
       eic_arch_wakeupen9: false
-    optional_signals: []
+    optional_signals:
+    - identifier: EXTERNAL_IRQ_0:EXTINT/0
+      pad: PA00
+      mode: Enabled
+      configuration: null
+      definition: Atmel:SAMD21_Drivers:0.0.1::SAMD21E17A-MF::optional_signal_definition::EIC.EXTINT.0
+      name: EIC/EXTINT/0
+      label: EXTINT/0
     variant: null
     clocks:
       domain_group:
@@ -709,6 +716,12 @@ drivers:
     clocks:
       domain_group: null
 pads:
+  PA00:
+    name: PA00
+    definition: Atmel:SAMD21_Drivers:0.0.1::SAMD21E17A-MF::pad::PA00
+    mode: Digital input
+    user_label: PA00
+    configuration: null
   OUT_LED_TX:
     name: PA06
     definition: Atmel:SAMD21_Drivers:0.0.1::SAMD21E17A-MF::pad::PA06
diff --git a/atmel_start_pins.h b/atmel_start_pins.h
index fac227d..8a4f719 100644
--- a/atmel_start_pins.h
+++ b/atmel_start_pins.h
@@ -21,6 +21,7 @@
 #define GPIO_PIN_FUNCTION_G 6
 #define GPIO_PIN_FUNCTION_H 7
 
+#define PA00 GPIO(GPIO_PORTA, 0)
 #define OUT_LED_TX GPIO(GPIO_PORTA, 6)
 #define OUT_XBEE_REMOTE_RESET GPIO(GPIO_PORTA, 7)
 #define IN_UART_TX GPIO(GPIO_PORTA, 8)
diff --git a/config/hpl_eic_config.h b/config/hpl_eic_config.h
index 711a9a6..59007af 100644
--- a/config/hpl_eic_config.h
+++ b/config/hpl_eic_config.h
@@ -682,6 +682,10 @@
 #endif
 // </e>
 
+#ifndef CONFIG_EIC_EXTINT_MAP
+#define CONFIG_EIC_EXTINT_MAP {0, PIN_PA00}, {0, 32},
+#endif
+
 // <<< end of configuration section >>>
 
 #endif // HPL_EIC_CONFIG_H
diff --git a/driver_init.c b/driver_init.c
index 4e111be..fd4dce7 100644
--- a/driver_init.c
+++ b/driver_init.c
@@ -25,6 +25,19 @@ void EXTERNAL_IRQ_0_init(void)
 {
 	_gclk_enable_channel(EIC_GCLK_ID, CONF_GCLK_EIC_SRC);
 
+	// Set pin direction to input
+	gpio_set_pin_direction(PA00, GPIO_DIRECTION_IN);
+
+	gpio_set_pin_pull_mode(PA00,
+	                       // <y> Pull configuration
+	                       // <id> pad_pull_config
+	                       // <GPIO_PULL_OFF"> Off
+	                       // <GPIO_PULL_UP"> Pull-up
+	                       // <GPIO_PULL_DOWN"> Pull-down
+	                       GPIO_PULL_OFF);
+
+	gpio_set_pin_function(PA00, PINMUX_PA00A_EIC_EXTINT0);
+
 	ext_irq_init();
 }
 
diff --git a/examples/driver_examples.c b/examples/driver_examples.c
index c0d9721..6c25223 100644
--- a/examples/driver_examples.c
+++ b/examples/driver_examples.c
@@ -10,11 +10,17 @@
 #include "driver_init.h"
 #include "utils.h"
 
+static void button_on_PA00_pressed(void)
+{
+}
+
 /**
  * Example of using EXTERNAL_IRQ_0
  */
 void EXTERNAL_IRQ_0_example(void)
 {
+
+	ext_irq_register(PIN_PA00, button_on_PA00_pressed);
 }
 
 /**
diff --git a/hal/src/hal_ext_irq.c b/hal/src/hal_ext_irq.c
index 2c1608c..9c5b6c2 100644
--- a/hal/src/hal_ext_irq.c
+++ b/hal/src/hal_ext_irq.c
@@ -33,7 +33,7 @@
 
 #include "hal_ext_irq.h"
 
-#define EXT_IRQ_AMOUNT 0
+#define EXT_IRQ_AMOUNT 2
 
 /**
  * \brief Driver version
diff --git a/hpl/eic/hpl_eic.c b/hpl/eic/hpl_eic.c
index eb9d9e1..0f4b968 100644
--- a/hpl/eic/hpl_eic.c
+++ b/hpl/eic/hpl_eic.c
@@ -69,7 +69,7 @@ static int ffs(int v)
 	}
 #endif
 
-#define EXT_IRQ_AMOUNT 0
+#define EXT_IRQ_AMOUNT 2
 
 /**
  * \brief EXTINTx and pin number map