diff --git a/inc/core/MicroBitComponent.h b/inc/core/MicroBitComponent.h
index fd30f88..f26b938 100644
--- a/inc/core/MicroBitComponent.h
+++ b/inc/core/MicroBitComponent.h
@@ -70,6 +70,7 @@ DEALINGS IN THE SOFTWARE.
 
 #define MICROBIT_ID_IO_INT1             33          //INT1
 #define MICROBIT_ID_IO_INT2             34          //INT2
+#define MICROBIT_ID_IO_INT3             35          //INT3
 
 #define MICROBIT_ID_MESSAGE_BUS_LISTENER            1021          // Message bus indication that a handler for a given ID has been registered.
 #define MICROBIT_ID_NOTIFY_ONE                      1022          // Notfication channel, for general purpose synchronisation
diff --git a/inc/drivers/MicroBitIO.h b/inc/drivers/MicroBitIO.h
index c94e927..34ecef1 100644
--- a/inc/drivers/MicroBitIO.h
+++ b/inc/drivers/MicroBitIO.h
@@ -62,6 +62,7 @@ class MicroBitIO
     MicroBitPin          P20;
     MicroBitPin          int1;
     MicroBitPin          int2;
+    MicroBitPin          int3;
 
     /**
       * Constructor.
@@ -77,7 +78,7 @@ class MicroBitIO
                int ID_P9, int ID_P10,int ID_P11,
                int ID_P12,int ID_P13,int ID_P14,
                int ID_P15,int ID_P16,int ID_P19,
-               int ID_P20, int ID_INT1, int ID_INT2);
+               int ID_P20, int ID_INT1, int ID_INT2, int ID_INT3);
 };
 
 #endif
diff --git a/source/drivers/FXOS8700.cpp b/source/drivers/FXOS8700.cpp
index a5b4d5f..da32638 100644
--- a/source/drivers/FXOS8700.cpp
+++ b/source/drivers/FXOS8700.cpp
@@ -104,9 +104,9 @@ int FXOS8700::configure()
     if (result != 0)
         return MICROBIT_I2C_ERROR;
 
-    // Configure PushPull Active LOW interrupt mode.
+    // Configure Open Drain Active LOW interrupt mode.
     // n.b. This may need to be reconfigured if the interrupt line is shared.
-    value = 0x00;
+    value = 0x01;
     result = i2c.writeRegister(address, FXOS8700_CTRL_REG3, value);
     if (result != 0)
         return MICROBIT_I2C_ERROR;
@@ -157,6 +157,9 @@ FXOS8700::FXOS8700(MicroBitI2C &_i2c, MicroBitPin &_int1, CoordinateSpace &coord
     // Store our identifiers.
     this->address = address;
 
+    // Enable pullup on the interrupt line
+    int1.setPull(PullUp);
+
     // Configure and enable the accelerometer.
     configure();
 }
diff --git a/source/drivers/MicroBitIO.cpp b/source/drivers/MicroBitIO.cpp
index f6a701b..e3be7cd 100644
--- a/source/drivers/MicroBitIO.cpp
+++ b/source/drivers/MicroBitIO.cpp
@@ -46,7 +46,7 @@ MicroBitIO::MicroBitIO(int ID_P0, int ID_P1, int ID_P2,
                        int ID_P9, int ID_P10,int ID_P11,
                        int ID_P12,int ID_P13,int ID_P14,
                        int ID_P15,int ID_P16,int ID_P19,
-                       int ID_P20, int ID_INT1, int ID_INT2) :
+                       int ID_P20, int ID_INT1, int ID_INT2, int ID_INT3) :
     P0 (ID_P0, MICROBIT_PIN_P0, PIN_CAPABILITY_ALL),             //P0 is the left most pad (ANALOG/DIGITAL/TOUCH)
     P1 (ID_P1, MICROBIT_PIN_P1, PIN_CAPABILITY_ALL),             //P1 is the middle pad (ANALOG/DIGITAL/TOUCH)
     P2 (ID_P2, MICROBIT_PIN_P2, PIN_CAPABILITY_ALL),             //P2 is the right most pad (ANALOG/DIGITAL/TOUCH)
@@ -67,6 +67,7 @@ MicroBitIO::MicroBitIO(int ID_P0, int ID_P1, int ID_P2,
     P19(ID_P19,MICROBIT_PIN_P19,PIN_CAPABILITY_STANDARD),        //SCL
     P20(ID_P20,MICROBIT_PIN_P20,PIN_CAPABILITY_STANDARD),        //SDA
     int1(ID_INT1,P0_28,PIN_CAPABILITY_STANDARD),                 //INT1
-    int2(ID_INT2,P0_29,PIN_CAPABILITY_STANDARD)                  //INT2
+    int2(ID_INT2,P0_29,PIN_CAPABILITY_STANDARD),                 //INT2
+    int3(ID_INT3,P0_27,PIN_CAPABILITY_STANDARD)                  //INT3
 {
 }