diff --git a/libraries/AP_Button/AP_Button.cpp b/libraries/AP_Button/AP_Button.cpp
new file mode 100644
index 0000000000..8c8bd4a822
--- /dev/null
+++ b/libraries/AP_Button/AP_Button.cpp
@@ -0,0 +1,175 @@
+/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include "AP_Button.h"
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <GCS_MAVLink/GCS.h>
+
+extern const AP_HAL::HAL& hal;
+
+const AP_Param::GroupInfo AP_Button::var_info[] = {
+
+    // @Param: ENABLE
+    // @DisplayName: Enable button reporting
+    // @Description: This enables the button checking module. When this is disabled the parameters for setting button inputs are not visible
+    // @Values: 0:Disabled, 1:Enabled
+    // @User: Advanced
+    AP_GROUPINFO_FLAGS("ENABLE", 0, AP_Button, enable, 0, AP_PARAM_FLAG_ENABLE),
+
+    // @Param: PIN1
+    // @DisplayName: First button Pin
+    // @Description: Digital pin number for first button input. 
+    // @User: Standard
+    // @Values: -1:Disabled,50:Pixhawk AUXOUT1,51:Pixhawk AUXOUT2,52:Pixhawk AUXOUT3,53:Pixhawk AUXOUT4,54:Pixhawk AUXOUT5,55:Pixhawk AUXOUT6,111:PX4 FMU Relay1,112:PX4 FMU Relay2,113:PX4IO Relay1,114:PX4IO Relay2,115:PX4IO ACC1,116:PX4IO ACC2
+    AP_GROUPINFO("PIN1",  1, AP_Button, pin[0], -1),
+
+    // @Param: PIN2
+    // @DisplayName: Second button Pin
+    // @Description: Digital pin number for second button input. 
+    // @User: Standard
+    // @Values: -1:Disabled,50:Pixhawk AUXOUT1,51:Pixhawk AUXOUT2,52:Pixhawk AUXOUT3,53:Pixhawk AUXOUT4,54:Pixhawk AUXOUT5,55:Pixhawk AUXOUT6,111:PX4 FMU Relay1,112:PX4 FMU Relay2,113:PX4IO Relay1,114:PX4IO Relay2,115:PX4IO ACC1,116:PX4IO ACC2
+    AP_GROUPINFO("PIN2",  2, AP_Button, pin[1], -1),
+
+    // @Param: PIN3
+    // @DisplayName: Third button Pin
+    // @Description: Digital pin number for third button input. 
+    // @User: Standard
+    // @Values: -1:Disabled,50:Pixhawk AUXOUT1,51:Pixhawk AUXOUT2,52:Pixhawk AUXOUT3,53:Pixhawk AUXOUT4,54:Pixhawk AUXOUT5,55:Pixhawk AUXOUT6,111:PX4 FMU Relay1,112:PX4 FMU Relay2,113:PX4IO Relay1,114:PX4IO Relay2,115:PX4IO ACC1,116:PX4IO ACC2
+    AP_GROUPINFO("PIN3",  3, AP_Button, pin[2], -1),
+
+    // @Param: PIN4
+    // @DisplayName: Fourth button Pin
+    // @Description: Digital pin number for fourth button input. 
+    // @User: Standard
+    // @Values: -1:Disabled,50:Pixhawk AUXOUT1,51:Pixhawk AUXOUT2,52:Pixhawk AUXOUT3,53:Pixhawk AUXOUT4,54:Pixhawk AUXOUT5,55:Pixhawk AUXOUT6,111:PX4 FMU Relay1,112:PX4 FMU Relay2,113:PX4IO Relay1,114:PX4IO Relay2,115:PX4IO ACC1,116:PX4IO ACC2
+    AP_GROUPINFO("PIN4",  4, AP_Button, pin[3], -1),
+
+    // @Param: REPORT_SEND
+    // @DisplayName: Report send time
+    // @Description: The duration in seconds that a BUTTON_CHANGE report is repeatedly sent to the GCS regarding a button changing state. Note that the BUTTON_CHANGE message is MAVLink2 only.
+    // @User: Standard
+    // @Range: 0 3600
+    AP_GROUPINFO("REPORT_SEND", 5, AP_Button, report_send_time, 10),
+
+    AP_GROUPEND    
+};
+
+
+// constructor
+AP_Button::AP_Button(void)
+{
+    AP_Param::setup_object_defaults(this, var_info);
+}
+
+/*
+  update and report, called from main loop
+ */
+void AP_Button::update(void)
+{
+    if (!enable) {
+        return;
+    }
+
+    // call setup pins at update rate (5Hz) to allow for runtime parameter change of pins
+    setup_pins();
+
+    if (!initialised) {
+        initialised = true;
+
+        // get initial mask
+        last_mask = get_mask();
+
+        // register 1kHz timer callback
+        hal.scheduler->register_timer_process(FUNCTOR_BIND_MEMBER(&AP_Button::timer_update, void));        
+    }
+
+    if (last_change_time_ms != 0 &&
+        (AP_HAL::millis() - last_report_ms) > AP_BUTTON_REPORT_PERIOD_MS &&
+        (AP_HAL::millis64() - last_change_time_ms) < report_send_time*1000ULL) {
+        // send a change report
+        last_report_ms = AP_HAL::millis();
+
+        // send a report to GCS
+        send_report();
+    }
+}
+
+/*
+  get current mask
+ */
+uint8_t AP_Button::get_mask(void)
+{
+    uint8_t mask = 0;
+    for (uint8_t i=0; i<AP_BUTTON_NUM_PINS; i++) {
+        if (pin[i] == -1) {
+            continue;
+        }
+        mask |= hal.gpio->read(pin[i]) << i;
+    }
+    return mask;
+}
+
+/*
+  called at 1kHz to check for button state change
+ */
+void AP_Button::timer_update(void)
+{
+    if (!enable) {
+        return;
+    }
+    uint8_t mask = get_mask();
+    if (mask != last_mask) {
+        last_mask = mask;
+        last_change_time_ms = AP_HAL::millis64();
+    }
+}
+
+/*
+  send a BUTTON_CHANGE report to the GCS
+ */
+void AP_Button::send_report(void)
+{
+    uint8_t chan_mask = GCS_MAVLINK::active_channel_mask();
+    uint32_t now = AP_HAL::millis();
+    for (uint8_t i=0; i<MAVLINK_COMM_NUM_BUFFERS; i++) {
+        if ((chan_mask & (1U<<i)) == 0) {
+            // not active
+            continue;
+        }
+        mavlink_channel_t chan = (mavlink_channel_t)i;
+        mavlink_msg_button_change_send(chan,
+                                       now,
+                                       (uint32_t)last_change_time_ms,
+                                       last_mask);
+    }
+}
+
+/*
+  setup the pins as input with pullup. We need pullup to give reliable
+  input with a pulldown button
+ */
+void AP_Button::setup_pins(void)
+{
+    for (uint8_t i=0; i<AP_BUTTON_NUM_PINS; i++) {
+        if (pin[i] == -1) {
+            continue;
+        }
+        hal.gpio->pinMode(pin[i], HAL_GPIO_INPUT);
+        // setup pullup
+        hal.gpio->write(pin[i], 1);
+    }
+}
diff --git a/libraries/AP_Button/AP_Button.h b/libraries/AP_Button/AP_Button.h
new file mode 100644
index 0000000000..f52175a2a9
--- /dev/null
+++ b/libraries/AP_Button/AP_Button.h
@@ -0,0 +1,67 @@
+/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <AP_HAL/AP_HAL.h>
+#include <AP_Param/AP_Param.h>
+
+// allow buttons for up to 4 pins
+#define AP_BUTTON_NUM_PINS 4
+
+// how often we send reports
+#define AP_BUTTON_REPORT_PERIOD_MS 1000
+
+class AP_Button {
+public:
+    // constructor
+    AP_Button(void);
+
+    static const struct AP_Param::GroupInfo var_info[];
+
+    // update button state and send messages, called periodically by main loop
+    void update(void);
+    
+private:
+    AP_Int8 enable;
+    AP_Int8 pin[AP_BUTTON_NUM_PINS];
+
+    // number of seconds to send change notifications
+    AP_Int16 report_send_time;
+
+    // last button press mask
+    uint8_t last_mask;
+
+    // when the mask last changed
+    uint64_t last_change_time_ms;
+
+    // time of last report
+    uint32_t last_report_ms;
+
+    // has the timer been installed?
+    bool initialised:1;
+    
+    // called by timer thread
+    void timer_update(void);
+
+    // get current mask
+    uint8_t get_mask(void);
+
+    // send a BUTTON_CHANGE report
+    void send_report(void);
+
+    // setup pins as pullup input
+    void setup_pins();
+};
+