ardupilot/ArduCopter/ArduCopter.pde

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-

#define THISFIRMWARE "ArduCopter V2.9-rc2"
/*
 *  ArduCopter Version 2.9
 *  Lead author:	Jason Short
 *  Based on code and ideas from the Arducopter team: Randy Mackay, Pat Hickey, Jose Julio, Jani Hirvinen, Andrew Tridgell, Justin Beech, Adam Rivera, Jean-Louis Naudin, Roberto Navoni
 *  Thanks to:	Chris Anderson, Mike Smith, Jordi Munoz, Doug Weibel, James Goppert, Benjamin Pelletier, Robert Lefebvre, Marco Robustini
 *
 *  This firmware is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  Special Thanks for Contributors:
 *
 *  Hein Hollander      :Octo Support
 *  Dani Saez           :V Ocoto Support
 *  Max Levine			:Tri Support, Graphics
 *  Jose Julio			:Stabilization Control laws
 *  Randy MacKay		:Heli Support
 *  Jani Hiriven		:Testing feedback
 *  Andrew Tridgell		:Mavlink Support
 *  James Goppert		:Mavlink Support
 *  Doug Weibel			:Libraries
 *  Mike Smith			:Libraries, Coding support
 *  HappyKillmore		:Mavlink GCS
 *  Michael Oborne		:Mavlink GCS
 *  Jack Dunkle			:Alpha testing
 *  Christof Schmid		:Alpha testing
 *  Oliver				:Piezo support
 *  Guntars				:Arming safety suggestion
 *  Igor van Airde      :Control Law optimization
 *  Jean-Louis Naudin   :Auto Landing
 *  Sandro Benigno      :Camera support
 *  Olivier Adler       :PPM Encoder
 *  John Arne Birkeland	:PPM Encoder
 *  Adam M Rivera		:Auto Compass Declination
 *  Marco Robustini		:Alpha testing
 *  Angel Fernandez		:Alpha testing
 *  Robert Lefebvre		:Heli Support & LEDs
 *  Amilcar Lucas		:mount and camera configuration
 *  Gregory Fletcher	:mount orientation math
 *	Leonard Hall 		:Flight Dynamics
 *
 *  And much more so PLEASE PM me on DIYDRONES to add your contribution to the List
 *
 *  Requires modified "mrelax" version of Arduino, which can be found here:
 *  http://code.google.com/p/ardupilot-mega/downloads/list
 *
 */

////////////////////////////////////////////////////////////////////////////////
// Header includes
////////////////////////////////////////////////////////////////////////////////

#include <math.h>
#include <stdio.h>
#include <stdarg.h>

// Common dependencies
#include <AP_Common.h>
#include <AP_Progmem.h>
#include <AP_Menu.h>
#include <AP_Param.h>
// AP_HAL
#include <AP_HAL.h>
#include <AP_HAL_AVR.h>
#include <AP_HAL_AVR_SITL.h>
#include <AP_HAL_PX4.h>
#include <AP_HAL_Empty.h>

// Application dependencies
#include <GCS_MAVLink.h>        // MAVLink GCS definitions
#include <AP_GPS.h>             // ArduPilot GPS library
#include <DataFlash.h>          // ArduPilot Mega Flash Memory Library
#include <AP_ADC.h>             // ArduPilot Mega Analog to Digital Converter Library
#include <AP_ADC_AnalogSource.h>
#include <AP_Baro.h>
#include <AP_Compass.h>         // ArduPilot Mega Magnetometer Library
#include <AP_Math.h>            // ArduPilot Mega Vector/Matrix math Library
#include <AP_Curve.h>           // Curve used to linearlise throttle pwm to thrust
#include <AP_InertialSensor.h>  // ArduPilot Mega Inertial Sensor (accel & gyro) Library
#include <AP_AHRS.h>
#include <APM_PI.h>             // PI library
#include <AC_PID.h>             // PID library
#include <RC_Channel.h>         // RC Channel Library
#include <AP_Motors.h>          // AP Motors library
#include <AP_RangeFinder.h>     // Range finder library
#include <AP_OpticalFlow.h>     // Optical Flow library
#include <Filter.h>             // Filter library
#include <AP_Buffer.h>          // APM FIFO Buffer
#include <AP_LeadFilter.h>      // GPS Lead filter
#include <AP_Relay.h>           // APM relay
#include <AP_Camera.h>          // Photo or video camera
#include <AP_Mount.h>           // Camera/Antenna mount
#include <AP_Airspeed.h>        // needed for AHRS build
#include <AP_InertialNav.h>     // ArduPilot Mega inertial navigation library
#include <AP_Declination.h>     // ArduPilot Mega Declination Helper Library
#include <AP_Limits.h>
#include <memcheck.h>
#include <SITL.h>

// AP_HAL to Arduino compatibility layer
#include "compat.h"
// Configuration
#include "defines.h"
#include "config.h"
#include "config_channels.h"

// Local modules
#include "Parameters.h"
#include "GCS.h"

////////////////////////////////////////////////////////////////////////////////
// cliSerial
////////////////////////////////////////////////////////////////////////////////
// cliSerial isn't strictly necessary - it is an alias for hal.console. It may
// be deprecated in favor of hal.console in later releases.
AP_HAL::BetterStream* cliSerial;

// N.B. we need to keep a static declaration which isn't guarded by macros
// at the top to cooperate with the prototype mangler. 

////////////////////////////////////////////////////////////////////////////////
// AP_HAL instance
////////////////////////////////////////////////////////////////////////////////

const AP_HAL::HAL& hal = AP_HAL_BOARD_DRIVER;


////////////////////////////////////////////////////////////////////////////////
// Parameters
////////////////////////////////////////////////////////////////////////////////
//
// Global parameters are all contained within the 'g' class.
//
static Parameters g;


////////////////////////////////////////////////////////////////////////////////
// prototypes
////////////////////////////////////////////////////////////////////////////////
static void update_events(void);

////////////////////////////////////////////////////////////////////////////////
// Dataflash
////////////////////////////////////////////////////////////////////////////////
#if CONFIG_HAL_BOARD == HAL_BOARD_APM2
DataFlash_APM2 DataFlash;
#elif CONFIG_HAL_BOARD == HAL_BOARD_APM1
DataFlash_APM1 DataFlash;
#elif CONFIG_HAL_BOARD == HAL_BOARD_AVR_SITL
DataFlash_SITL DataFlash;
#else
DataFlash_Empty DataFlash;
#endif


////////////////////////////////////////////////////////////////////////////////
// the rate we run the main loop at
////////////////////////////////////////////////////////////////////////////////
static const AP_InertialSensor::Sample_rate ins_sample_rate = AP_InertialSensor::RATE_200HZ;

////////////////////////////////////////////////////////////////////////////////
// Sensors
////////////////////////////////////////////////////////////////////////////////
//
// There are three basic options related to flight sensor selection.
//
// - Normal flight mode. Real sensors are used.
// - HIL Attitude mode. Most sensors are disabled, as the HIL
//   protocol supplies attitude information directly.
// - HIL Sensors mode. Synthetic sensors are configured that
//   supply data from the simulation.
//

// All GPS access should be through this pointer.
static GPS         *g_gps;

// flight modes convenience array
static AP_Int8 *flight_modes = &g.flight_mode1;

#if HIL_MODE == HIL_MODE_DISABLED

 #if CONFIG_ADC == ENABLED
AP_ADC_ADS7844 adc;
 #endif

 #if CONFIG_IMU_TYPE == CONFIG_IMU_MPU6000
AP_InertialSensor_MPU6000 ins;
#elif CONFIG_IMU_TYPE == CONFIG_IMU_OILPAN
AP_InertialSensor_Oilpan ins(&adc);
#elif CONFIG_IMU_TYPE == CONFIG_IMU_SITL
AP_InertialSensor_Stub ins;
#elif CONFIG_IMU_TYPE == CONFIG_IMU_PX4
AP_InertialSensor_PX4 ins;
 #endif

 #if CONFIG_HAL_BOARD == HAL_BOARD_AVR_SITL
 // When building for SITL we use the HIL barometer and compass drivers
AP_Baro_BMP085_HIL barometer;
AP_Compass_HIL compass;
SITL sitl;
 #else
// Otherwise, instantiate a real barometer and compass driver
  #if CONFIG_BARO == AP_BARO_BMP085
AP_Baro_BMP085 barometer;
  #elif CONFIG_BARO == AP_BARO_PX4
AP_Baro_PX4 barometer;
  #elif CONFIG_BARO == AP_BARO_MS5611
   #if CONFIG_MS5611_SERIAL == SPI
AP_Baro_MS5611 barometer(&AP_Baro_MS5611::spi);
   #elif CONFIG_MS5611_SERIAL == I2C
AP_Baro_MS5611 barometer(&AP_Baro_MS5611::i2c);
   #else
    #error Unrecognized CONFIG_MS5611_SERIAL setting.
   #endif
  #endif

 #if CONFIG_HAL_BOARD == HAL_BOARD_PX4
AP_Compass_PX4 compass;
 #else
AP_Compass_HMC5843 compass;
 #endif
 #endif

 #if OPTFLOW == ENABLED
AP_OpticalFlow_ADNS3080 optflow;
 #else
AP_OpticalFlow optflow;
 #endif

// real GPS selection
 #if   GPS_PROTOCOL == GPS_PROTOCOL_AUTO
AP_GPS_Auto     g_gps_driver(&g_gps);

 #elif GPS_PROTOCOL == GPS_PROTOCOL_NMEA
AP_GPS_NMEA     g_gps_driver();

 #elif GPS_PROTOCOL == GPS_PROTOCOL_SIRF
AP_GPS_SIRF     g_gps_driver();

 #elif GPS_PROTOCOL == GPS_PROTOCOL_UBLOX
AP_GPS_UBLOX    g_gps_driver();

 #elif GPS_PROTOCOL == GPS_PROTOCOL_MTK
AP_GPS_MTK      g_gps_driver();

 #elif GPS_PROTOCOL == GPS_PROTOCOL_MTK19
AP_GPS_MTK19    g_gps_driver();

 #elif GPS_PROTOCOL == GPS_PROTOCOL_NONE
AP_GPS_None     g_gps_driver();

 #else
  #error Unrecognised GPS_PROTOCOL setting.
 #endif // GPS PROTOCOL

 #if DMP_ENABLED == ENABLED && CONFIG_HAL_BOARD == HAL_BOARD_APM2
AP_AHRS_MPU6000  ahrs(&ins, g_gps);               // only works with APM2
 #else
AP_AHRS_DCM ahrs(&ins, g_gps);
 #endif

// ahrs2 object is the secondary ahrs to allow running DMP in parallel with DCM
  #if SECONDARY_DMP_ENABLED == ENABLED && CONFIG_HAL_BOARD == HAL_BOARD_APM2
AP_AHRS_MPU6000  ahrs2(&ins, g_gps);               // only works with APM2
  #endif

#elif HIL_MODE == HIL_MODE_SENSORS
// sensor emulators
AP_ADC_HIL              adc;
AP_Baro_BMP085_HIL      barometer;
AP_Compass_HIL          compass;
AP_GPS_HIL              g_gps_driver;
AP_InertialSensor_Stub  ins;
AP_AHRS_DCM             ahrs(&ins, g_gps);


static int32_t gps_base_alt;

#elif HIL_MODE == HIL_MODE_ATTITUDE
AP_ADC_HIL              adc;
AP_InertialSensor_Stub  ins;
AP_AHRS_HIL             ahrs(&ins, g_gps);
AP_GPS_HIL              g_gps_driver;
AP_Compass_HIL          compass;                  // never used
AP_Baro_BMP085_HIL      barometer;

 #if OPTFLOW == ENABLED
  #if CONFIG_HAL_BOARD == HAL_BOARD_APM2
AP_OpticalFlow_ADNS3080 optflow;
  #else
AP_OpticalFlow_ADNS3080 optflow;
  #endif    // CONFIG_HAL_BOARD == HAL_BOARD_APM2
 #endif     // OPTFLOW == ENABLED

static int32_t gps_base_alt;
#else
 #error Unrecognised HIL_MODE setting.
#endif // HIL MODE

////////////////////////////////////////////////////////////////////////////////
// GCS selection
////////////////////////////////////////////////////////////////////////////////
GCS_MAVLINK gcs0;
GCS_MAVLINK gcs3;

////////////////////////////////////////////////////////////////////////////////
// SONAR selection
////////////////////////////////////////////////////////////////////////////////
//

#if CONFIG_SONAR == ENABLED
ModeFilterInt16_Size5 sonar_mode_filter(2);
AP_HAL::AnalogSource *sonar_analog_source;
AP_RangeFinder_MaxsonarXL *sonar;
#endif

////////////////////////////////////////////////////////////////////////////////
// User variables
////////////////////////////////////////////////////////////////////////////////
#ifdef USERHOOK_VARIABLES
 #include USERHOOK_VARIABLES
#endif

////////////////////////////////////////////////////////////////////////////////
// Global variables
////////////////////////////////////////////////////////////////////////////////

/* Radio values
 *               Channel assignments
 *                       1	Ailerons (rudder if no ailerons)
 *                       2	Elevator
 *                       3	Throttle
 *                       4	Rudder (if we have ailerons)
 *                       5	Mode - 3 position switch
 *                       6  User assignable
 *                       7	trainer switch - sets throttle nominal (toggle switch), sets accels to Level (hold > 1 second)
 *                       8	TBD
 *               Each Aux channel can be configured to have any of the available auxiliary functions assigned to it.
 *               See libraries/RC_Channel/RC_Channel_aux.h for more information
 */

//Documentation of GLobals:
static union {
    struct {
        uint8_t home_is_set        : 1; // 1
        uint8_t simple_mode        : 1; // 2    // This is the state of simple mode
        uint8_t manual_attitude    : 1; // 3
        uint8_t manual_throttle    : 1; // 4

        uint8_t low_battery        : 1; // 5    // Used to track if the battery is low - LED output flashes when the batt is low
        uint8_t loiter_override    : 1; // 6    // Are we navigating while holding a positon? This is set to false once the speed drops below 1m/s
        uint8_t armed              : 1; // 7
        uint8_t auto_armed         : 1; // 8

        uint8_t failsafe           : 1; // 9    // A status flag for the failsafe state
        uint8_t do_flip            : 1; // 10   // Used to enable flip code
        uint8_t takeoff_complete   : 1; // 11
        uint8_t land_complete      : 1; // 12
        uint8_t compass_status     : 1; // 13
        uint8_t gps_status         : 1; // 14
        uint8_t fast_corner        : 1; // 15   // should we take the waypoint quickly or slow down?
    };
    uint16_t value;
} ap;


static struct AP_System{
    uint8_t GPS_light               : 1; // 1   // Solid indicates we have full 3D lock and can navigate, flash = read
    uint8_t motor_light             : 1; // 2   // Solid indicates Armed state
    uint8_t new_radio_frame         : 1; // 3   // Set true if we have new PWM data to act on from the Radio
    uint8_t nav_ok                  : 1; // 4   // deprecated
    uint8_t CH7_flag                : 1; // 5   // manages state of the ch7 toggle switch
    uint8_t usb_connected           : 1; // 6   // true if APM is powered from USB connection
    uint8_t run_50hz_loop           : 1; // 7   // toggles the 100hz loop for 50hz
    uint8_t alt_sensor_flag         : 1; // 8   // used to track when to read sensors vs estimate alt
    uint8_t yaw_stopped             : 1; // 9   // Used to manage the Yaw hold capabilities

} ap_system;


////////////////////////////////////////////////////////////////////////////////
// velocity in lon and lat directions calculated from GPS position and accelerometer data
// updated after GPS read - 5-10hz
static int16_t lon_speed;       // expressed in cm/s.  positive numbers mean moving east
static int16_t lat_speed;       // expressed in cm/s.  positive numbers when moving north

// The difference between the desired rate of travel and the actual rate of travel
// updated after GPS read - 5-10hz
static int16_t x_rate_error;
static int16_t y_rate_error;

////////////////////////////////////////////////////////////////////////////////
// Radio
////////////////////////////////////////////////////////////////////////////////
// This is the state of the flight control system
// There are multiple states defined such as STABILIZE, ACRO,
static int8_t control_mode = STABILIZE;
// Used to maintain the state of the previous control switch position
// This is set to -1 when we need to re-read the switch
static uint8_t oldSwitchPosition;

// receiver RSSI
static uint8_t receiver_rssi;


////////////////////////////////////////////////////////////////////////////////
// Motor Output
////////////////////////////////////////////////////////////////////////////////
#if FRAME_CONFIG == QUAD_FRAME
 #define MOTOR_CLASS AP_MotorsQuad
#endif
#if FRAME_CONFIG == TRI_FRAME
 #define MOTOR_CLASS AP_MotorsTri
#endif
#if FRAME_CONFIG == HEXA_FRAME
 #define MOTOR_CLASS AP_MotorsHexa
#endif
#if FRAME_CONFIG == Y6_FRAME
 #define MOTOR_CLASS AP_MotorsY6
#endif
#if FRAME_CONFIG == OCTA_FRAME
 #define MOTOR_CLASS AP_MotorsOcta
#endif
#if FRAME_CONFIG == OCTA_QUAD_FRAME
 #define MOTOR_CLASS AP_MotorsOctaQuad
#endif
#if FRAME_CONFIG == HELI_FRAME
 #define MOTOR_CLASS AP_MotorsHeli
#endif

#if FRAME_CONFIG == HELI_FRAME  // helicopter constructor requires more arguments
MOTOR_CLASS motors(&g.rc_1, &g.rc_2, &g.rc_3, &g.rc_4, &g.rc_8, &g.heli_servo_1, &g.heli_servo_2, &g.heli_servo_3, &g.heli_servo_4);
#elif FRAME_CONFIG == TRI_FRAME  // tri constructor requires additional rc_7 argument to allow tail servo reversing
MOTOR_CLASS motors(&g.rc_1, &g.rc_2, &g.rc_3, &g.rc_4, &g.rc_7);
#else
MOTOR_CLASS motors(&g.rc_1, &g.rc_2, &g.rc_3, &g.rc_4);
#endif

////////////////////////////////////////////////////////////////////////////////
// PIDs
////////////////////////////////////////////////////////////////////////////////
// This is a convienience accessor for the IMU roll rates. It's currently the raw IMU rates
// and not the adjusted omega rates, but the name is stuck
static Vector3f omega;
// This is used to hold radio tuning values for in-flight CH6 tuning
float tuning_value;

////////////////////////////////////////////////////////////////////////////////
// LED output
////////////////////////////////////////////////////////////////////////////////
// This is current status for the LED lights state machine
// setting this value changes the output of the LEDs
static uint8_t led_mode = NORMAL_LEDS;
// Blinking indicates GPS status
static uint8_t copter_leds_GPS_blink;
// Blinking indicates battery status
static uint8_t copter_leds_motor_blink;
// Navigation confirmation blinks
static int8_t copter_leds_nav_blink;

////////////////////////////////////////////////////////////////////////////////
// GPS variables
////////////////////////////////////////////////////////////////////////////////
// This is used to scale GPS values for EEPROM storage
// 10^7 times Decimal GPS means 1 == 1cm
// This approximation makes calculations integer and it's easy to read
static const float t7 = 10000000.0;
// We use atan2 and other trig techniques to calaculate angles
// We need to scale the longitude up to make these calcs work
// to account for decreasing distance between lines of longitude away from the equator
static float scaleLongUp = 1;
// Sometimes we need to remove the scaling for distance calcs
static float scaleLongDown = 1;


////////////////////////////////////////////////////////////////////////////////
// Mavlink specific
////////////////////////////////////////////////////////////////////////////////
// Used by Mavlink for unknow reasons
static const float radius_of_earth = 6378100;   // meters

// Unions for getting byte values
union float_int {
    int32_t int_value;
    float float_value;
} float_int;


////////////////////////////////////////////////////////////////////////////////
// Location & Navigation
////////////////////////////////////////////////////////////////////////////////
// This is the angle from the copter to the "next_WP" location in degrees * 100
static int32_t wp_bearing;
// Status of the Waypoint tracking mode. Options include:
// NO_NAV_MODE, WP_MODE, LOITER_MODE, CIRCLE_MODE
static uint8_t wp_control;
// Register containing the index of the current navigation command in the mission script
static int16_t command_nav_index;
// Register containing the index of the previous navigation command in the mission script
// Used to manage the execution of conditional commands
static uint8_t prev_nav_index;
// Register containing the index of the current conditional command in the mission script
static uint8_t command_cond_index;
// Used to track the required WP navigation information
// options include
// NAV_ALTITUDE - have we reached the desired altitude?
// NAV_LOCATION - have we reached the desired location?
// NAV_DELAY    - have we waited at the waypoint the desired time?
static uint8_t wp_verify_byte;                                                  // used for tracking state of navigating waypoints
// used to limit the speed ramp up of WP navigation
// Acceleration is limited to 1m/s/s
static int16_t max_speed_old;
// Used to track how many cm we are from the "next_WP" location
static int32_t long_error, lat_error;
static int16_t control_roll;
static int16_t control_pitch;
static uint8_t rtl_state;

////////////////////////////////////////////////////////////////////////////////
// Orientation
////////////////////////////////////////////////////////////////////////////////
// Convienience accessors for commonly used trig functions. These values are generated
// by the DCM through a few simple equations. They are used throughout the code where cos and sin
// would normally be used.
// The cos values are defaulted to 1 to get a decent initial value for a level state
static float cos_roll_x         = 1;
static float cos_pitch_x        = 1;
static float cos_yaw_x          = 1;
static float sin_yaw_y;
static float sin_roll;
static float sin_pitch;

////////////////////////////////////////////////////////////////////////////////
// SIMPLE Mode
////////////////////////////////////////////////////////////////////////////////
// Used to track the orientation of the copter for Simple mode. This value is reset at each arming
// or in SuperSimple mode when the copter leaves a 20m radius from home.
static int32_t initial_simple_bearing;

////////////////////////////////////////////////////////////////////////////////
// Rate contoller targets
////////////////////////////////////////////////////////////////////////////////
static uint8_t rate_targets_frame = EARTH_FRAME;    // indicates whether rate targets provided in earth or body frame
static int32_t roll_rate_target_ef = 0;
static int32_t pitch_rate_target_ef = 0;
static int32_t yaw_rate_target_ef = 0;
static int32_t roll_rate_target_bf = 0;     // body frame roll rate target
static int32_t pitch_rate_target_bf = 0;    // body frame pitch rate target
static int32_t yaw_rate_target_bf = 0;      // body frame yaw rate target

////////////////////////////////////////////////////////////////////////////////
// Throttle variables
////////////////////////////////////////////////////////////////////////////////
static int16_t throttle_accel_target_ef;    // earth frame throttle acceleration target
static bool throttle_accel_controller_active;   // true when accel based throttle controller is active, false when higher level throttle controllers are providing throttle output directly
static float throttle_avg;                  // g.throttle_cruise as a float
static int16_t desired_climb_rate;          // pilot desired climb rate - for logging purposes only


////////////////////////////////////////////////////////////////////////////////
// ACRO Mode
////////////////////////////////////////////////////////////////////////////////
// Used to control Axis lock
int32_t roll_axis;
int32_t pitch_axis;

// Filters
AP_LeadFilter xLeadFilter;      // Long GPS lag filter
AP_LeadFilter yLeadFilter;      // Lat  GPS lag filter
#if FRAME_CONFIG == HELI_FRAME
LowPassFilterFloat rate_roll_filter;    // Rate Roll filter
LowPassFilterFloat rate_pitch_filter;   // Rate Pitch filter
// LowPassFilterFloat rate_yaw_filter;     // Rate Yaw filter
#endif // HELI_FRAME

// Barometer filter
AverageFilterInt32_Size5 baro_filter;

////////////////////////////////////////////////////////////////////////////////
// Circle Mode / Loiter control
////////////////////////////////////////////////////////////////////////////////
// used to determin the desired location in Circle mode
// increments at circle_rate / second
static float circle_angle;
// used to control the speed of Circle mode
// units are in radians, default is 5° per second
static const float circle_rate = 0.0872664625;
// used to track the delat in Circle Mode
static int32_t old_wp_bearing;
// deg : how many times to circle * 360 for Loiter/Circle Mission command
static int16_t loiter_total;
// deg : how far we have turned around a waypoint
static int16_t loiter_sum;
// How long we should stay in Loiter Mode for mission scripting
static uint16_t loiter_time_max;
// How long have we been loitering - The start time in millis
static uint32_t loiter_time;
// The synthetic location created to make the copter do circles around a WP
static struct   Location circle_WP;


////////////////////////////////////////////////////////////////////////////////
// CH7 control
////////////////////////////////////////////////////////////////////////////////
// This register tracks the current Mission Command index when writing
// a mission using CH7 in flight
static int8_t CH7_wp_index;


////////////////////////////////////////////////////////////////////////////////
// Battery Sensors
////////////////////////////////////////////////////////////////////////////////
// Battery Voltage of battery, initialized above threshold for filter
static float battery_voltage1 = LOW_VOLTAGE * 1.05;
// refers to the instant amp draw – based on an Attopilot Current sensor
static float current_amps1;
// refers to the total amps drawn – based on an Attopilot Current sensor
static float current_total1;


////////////////////////////////////////////////////////////////////////////////
// Altitude
////////////////////////////////////////////////////////////////////////////////
// The cm we are off in altitude from next_WP.alt – Positive value means we are below the WP
static int32_t altitude_error;
// The cm/s we are moving up or down based on sensor data - Positive = UP
static int16_t climb_rate_actual;
// Used to dither our climb_rate over 50hz
static int16_t climb_rate_error;
// The cm/s we are moving up or down based on filtered data - Positive = UP
static int16_t climb_rate;
// The altitude as reported by Sonar in cm – Values are 20 to 700 generally.
static int16_t sonar_alt;
static bool sonar_alt_ok;   // true if we can trust the altitude from the sonar
// The climb_rate as reported by sonar in cm/s
static int16_t sonar_rate;
// The altitude as reported by Baro in cm – Values can be quite high
static int32_t baro_alt;
// The climb_rate as reported by Baro in cm/s
static int16_t baro_rate;

static int16_t saved_toy_throttle;


////////////////////////////////////////////////////////////////////////////////
// flight modes
////////////////////////////////////////////////////////////////////////////////
// Flight modes are combinations of Roll/Pitch, Yaw and Throttle control modes
// Each Flight mode is a unique combination of these modes
//
// The current desired control scheme for Yaw
static uint8_t yaw_mode;
// The current desired control scheme for roll and pitch / navigation
static uint8_t roll_pitch_mode;
// The current desired control scheme for altitude hold
static uint8_t throttle_mode;


////////////////////////////////////////////////////////////////////////////////
// flight specific
////////////////////////////////////////////////////////////////////////////////
// An additional throttle added to keep the copter at the same altitude when banking
static int16_t angle_boost;
// counter to verify landings
static uint16_t land_detector;


////////////////////////////////////////////////////////////////////////////////
// Navigation general
////////////////////////////////////////////////////////////////////////////////
// The location of home in relation to the copter, updated every GPS read
static int32_t home_bearing;
// distance between plane and home in cm
static int32_t home_distance;
// distance between plane and next_WP in cm
// is not static because AP_Camera uses it
int32_t wp_distance;

////////////////////////////////////////////////////////////////////////////////
// 3D Location vectors
////////////////////////////////////////////////////////////////////////////////
// home location is stored when we have a good GPS lock and arm the copter
// Can be reset each the copter is re-armed
static struct   Location home;
// Current location of the copter
static struct   Location current_loc;
// Next WP is the desired location of the copter - the next waypoint or loiter location
static struct   Location next_WP;
// Prev WP is used to get the optimum path from one WP to the next
static struct   Location prev_WP;
// Holds the current loaded command from the EEPROM for navigation
static struct   Location command_nav_queue;
// Holds the current loaded command from the EEPROM for conditional scripts
static struct   Location command_cond_queue;
// Holds the current loaded command from the EEPROM for guided mode
static struct   Location guided_WP;


////////////////////////////////////////////////////////////////////////////////
// Crosstrack
////////////////////////////////////////////////////////////////////////////////
// deg * 100, The original angle to the next_WP when the next_WP was set
// Also used to check when we pass a WP
static int32_t original_wp_bearing;
// The amount of angle correction applied to wp_bearing to bring the copter back on its optimum path
static int16_t crosstrack_error;


////////////////////////////////////////////////////////////////////////////////
// Navigation Roll/Pitch functions
////////////////////////////////////////////////////////////////////////////////
// all angles are deg * 100 : target yaw angle
// The Commanded ROll from the autopilot.
static int32_t nav_roll;
// The Commanded pitch from the autopilot. negative Pitch means go forward.
static int32_t nav_pitch;
// The desired bank towards North (Positive) or South (Negative)
static int32_t auto_roll;
static int32_t auto_pitch;

// Don't be fooled by the fact that Pitch is reversed from Roll in its sign!
static int16_t nav_lat;
// The desired bank towards East (Positive) or West (Negative)
static int16_t nav_lon;
// The Commanded ROll from the autopilot based on optical flow sensor.
static int32_t of_roll;
// The Commanded pitch from the autopilot based on optical flow sensor. negative Pitch means go forward.
static int32_t of_pitch;


////////////////////////////////////////////////////////////////////////////////
// Navigation Throttle control
////////////////////////////////////////////////////////////////////////////////
// The Commanded Throttle from the autopilot.
static int16_t nav_throttle;    // 0-1000 for throttle control
// This is a simple counter to track the amount of throttle used during flight
// This could be useful later in determining and debuging current usage and predicting battery life
static uint32_t throttle_integrator;

////////////////////////////////////////////////////////////////////////////////
// Climb rate control
////////////////////////////////////////////////////////////////////////////////
// Time when we intiated command in millis - used for controlling decent rate
// Used to track the altitude offset for climbrate control
static int8_t alt_change_flag;

////////////////////////////////////////////////////////////////////////////////
// Navigation Yaw control
////////////////////////////////////////////////////////////////////////////////
// The Commanded Yaw from the autopilot.
static int32_t nav_yaw;
static uint8_t yaw_timer;
// Yaw will point at this location if yaw_mode is set to YAW_LOOK_AT_LOCATION
static struct Location yaw_look_at_WP;
// bearing from current location to the yaw_look_at_WP
static int32_t yaw_look_at_WP_bearing;
// yaw used for YAW_LOOK_AT_HEADING yaw_mode
static int32_t yaw_look_at_heading;
// Deg/s we should turn
static int16_t yaw_look_at_heading_slew;



////////////////////////////////////////////////////////////////////////////////
// Repeat Mission Scripting Command
////////////////////////////////////////////////////////////////////////////////
// The type of repeating event - Toggle a servo channel, Toggle the APM1 relay, etc
static uint8_t event_id;
// Used to manage the timimng of repeating events
static uint32_t event_timer;
// How long to delay the next firing of event in millis
static uint16_t event_delay;
// how many times to fire : 0 = forever, 1 = do once, 2 = do twice
static int16_t event_repeat;
// per command value, such as PWM for servos
static int16_t event_value;
// the stored value used to undo commands - such as original PWM command
static int16_t event_undo_value;

////////////////////////////////////////////////////////////////////////////////
// Delay Mission Scripting Command
////////////////////////////////////////////////////////////////////////////////
static int32_t condition_value;  // used in condition commands (eg delay, change alt, etc.)
static uint32_t condition_start;


////////////////////////////////////////////////////////////////////////////////
// IMU variables
////////////////////////////////////////////////////////////////////////////////
// Integration time for the gyros (DCM algorithm)
// Updated with the fast loop
static float G_Dt = 0.02;

////////////////////////////////////////////////////////////////////////////////
// Inertial Navigation
////////////////////////////////////////////////////////////////////////////////
#if INERTIAL_NAV_XY == ENABLED || INERTIAL_NAV_Z == ENABLED
AP_InertialNav inertial_nav(&ahrs, &ins, &barometer, &g_gps);
#endif

////////////////////////////////////////////////////////////////////////////////
// Performance monitoring
////////////////////////////////////////////////////////////////////////////////
// Used to manage the rate of performance logging messages
static int16_t perf_mon_counter;
// The number of GPS fixes we have had
static int16_t gps_fix_count;

// System Timers
// --------------
// Time in microseconds of main control loop
static uint32_t fast_loopTimer;
// Time in microseconds of 50hz control loop
static uint32_t fiftyhz_loopTimer;
// Counters for branching from 10 hz control loop
static uint8_t medium_loopCounter;
// Counters for branching from 3 1/3hz control loop
static uint8_t slow_loopCounter;
// Counters for branching at 1 hz
static uint8_t counter_one_herz;
// Counter of main loop executions.  Used for performance monitoring and failsafe processing
static uint16_t mainLoop_count;
// Delta Time in milliseconds for navigation computations, updated with every good GPS read
static float dTnav;
// Counters for branching from 4 minute control loop used to save Compass offsets
static int16_t superslow_loopCounter;
// Loiter timer - Records how long we have been in loiter
static uint32_t rtl_loiter_start_time;
// disarms the copter while in Acro or Stabilize mode after 30 seconds of no flight
static uint8_t auto_disarming_counter;
// prevents duplicate GPS messages from entering system
static uint32_t last_gps_time;

// Used to exit the roll and pitch auto trim function
static uint8_t auto_trim_counter;

// Reference to the relay object (APM1 -> PORTL 2) (APM2 -> PORTB 7)
AP_Relay relay;

//Reference to the camera object (it uses the relay object inside it)
#if CAMERA == ENABLED
  AP_Camera camera(&relay);
#endif

// a pin for reading the receiver RSSI voltage. The scaling by 0.25
// is to take the 0 to 1024 range down to an 8 bit range for MAVLink
AP_HAL::AnalogSource* rssi_analog_source;


// Input sources for battery voltage, battery current, board vcc
AP_HAL::AnalogSource* batt_volt_analog_source;
AP_HAL::AnalogSource* batt_curr_analog_source;
AP_HAL::AnalogSource* board_vcc_analog_source;


#if CLI_ENABLED == ENABLED
    static int8_t   setup_show (uint8_t argc, const Menu::arg *argv);
#endif

// Camera/Antenna mount tracking and stabilisation stuff
// --------------------------------------
#if MOUNT == ENABLED
// current_loc uses the baro/gps soloution for altitude rather than gps only.
// mabe one could use current_loc for lat/lon too and eliminate g_gps alltogether?
AP_Mount camera_mount(&current_loc, g_gps, &ahrs, 0);
#endif

#if MOUNT2 == ENABLED
// current_loc uses the baro/gps soloution for altitude rather than gps only.
// mabe one could use current_loc for lat/lon too and eliminate g_gps alltogether?
AP_Mount camera_mount2(&current_loc, g_gps, &ahrs, 1);
#endif


////////////////////////////////////////////////////////////////////////////////
// Experimental AP_Limits library - set constraints, limits, fences, minima, maxima on various parameters
////////////////////////////////////////////////////////////////////////////////
#if AP_LIMITS == ENABLED
AP_Limits               limits;
AP_Limit_GPSLock        gpslock_limit(g_gps);
AP_Limit_Geofence       geofence_limit(FENCE_START_BYTE, FENCE_WP_SIZE, MAX_FENCEPOINTS, g_gps, &home, &current_loc);
AP_Limit_Altitude       altitude_limit(&current_loc);
#endif

////////////////////////////////////////////////////////////////////////////////
// function definitions to keep compiler from complaining about undeclared functions
////////////////////////////////////////////////////////////////////////////////
void get_throttle_althold(int32_t target_alt, int16_t min_climb_rate, int16_t max_climb_rate);

////////////////////////////////////////////////////////////////////////////////
// Top-level logic
////////////////////////////////////////////////////////////////////////////////

// setup the var_info table
AP_Param param_loader(var_info, WP_START_BYTE);

void setup() {
    cliSerial = hal.console;

    // Load the default values of variables listed in var_info[]s
    AP_Param::setup_sketch_defaults();

#if CONFIG_SONAR == ENABLED
 #if CONFIG_SONAR_SOURCE == SONAR_SOURCE_ADC
    sonar_analog_source = new AP_ADC_AnalogSource(
            &adc, CONFIG_SONAR_SOURCE_ADC_CHANNEL, 0.25);
 #elif CONFIG_SONAR_SOURCE == SONAR_SOURCE_ANALOG_PIN
    sonar_analog_source = hal.analogin->channel(
            CONFIG_SONAR_SOURCE_ANALOG_PIN);
 #else
  #warning "Invalid CONFIG_SONAR_SOURCE"
 #endif
    sonar = new AP_RangeFinder_MaxsonarXL(sonar_analog_source,
            &sonar_mode_filter);
#endif

    rssi_analog_source      = hal.analogin->channel(g.rssi_pin, 0.25);
    batt_volt_analog_source = hal.analogin->channel(g.battery_volt_pin);
    batt_curr_analog_source = hal.analogin->channel(g.battery_curr_pin);
    board_vcc_analog_source = hal.analogin->channel(ANALOG_INPUT_BOARD_VCC);

    memcheck_init();
    init_ardupilot();
}

/*
  return true if the main loop is ready to run. This is used by
  potentially expensive functions that are not timing critical, to
  defer the expensive processing until after the main loop has run.
 */
static bool main_loop_ready(void)
{
    return ins.num_samples_available() >= 2;
}


void loop()
{
    uint32_t timer = micros();

    // We want this to execute fast
    // ----------------------------
    if (main_loop_ready()) {

#if 0
        uint16_t num_samples = ins.num_samples_available();
        static uint16_t counter;
        if (num_samples != 2 || (counter++ % 200 == 0)) {
            cliSerial->printf_P(PSTR("num_samples=%u dt=%u\n"),
                                (unsigned)num_samples,
                                (unsigned)(timer - fast_loopTimer));
        }
#endif

        #if DEBUG_FAST_LOOP == ENABLED
        Log_Write_Data(DATA_FAST_LOOP, (int32_t)(timer - fast_loopTimer));
        #endif

        // check loop time
        perf_info_check_loop_time(timer - fast_loopTimer);

        G_Dt            = (float)(timer - fast_loopTimer) / 1000000.f;                  // used by PI Loops
        fast_loopTimer  = timer;

        // for mainloop failure monitoring
        mainLoop_count++;

        // Execute the fast loop
        // ---------------------
        fast_loop();

        // run the 50hz loop 1/2 the time
        ap_system.run_50hz_loop = !ap_system.run_50hz_loop;

        if(ap_system.run_50hz_loop) {

            #if DEBUG_MED_LOOP == ENABLED
            Log_Write_Data(DATA_MED_LOOP, (int32_t)(timer - fiftyhz_loopTimer));
            #endif

            // store the micros for the 50 hz timer
            fiftyhz_loopTimer = timer;

            // check for new GPS messages
            // --------------------------
            update_GPS();

            // run navigation routines
            update_navigation();

            // perform 10hz tasks
            // ------------------
            medium_loop();

            // Stuff to run at full 50hz, but after the med loops
            // --------------------------------------------------
            fifty_hz_loop();

            counter_one_herz++;

            // trgger our 1 hz loop
            if(counter_one_herz >= 50) {
                super_slow_loop();
                counter_one_herz = 0;
            }
            perf_mon_counter++;
            if (perf_mon_counter >= 500 ) {     // 500 iterations at 50hz = 10 seconds
                if (g.log_bitmask & MASK_LOG_PM)
                    Log_Write_Performance();
                perf_info_reset();
                gps_fix_count           = 0;
                perf_mon_counter        = 0;
            }
        }else{
            // process communications with the GCS
            gcs_check();
        }
    } else {
        if (timer - fast_loopTimer < 9000) {
            // we have some spare cycles available
            // less than 10ms has passed. We have at least one millisecond
            // of free time. The most useful thing to do with that time is
            // to accumulate some sensor readings, specifically the
            // compass, which is often very noisy but is not interrupt
            // driven, so it can't accumulate readings by itself
            if (g.compass_enabled) {
                compass.accumulate();
            }
        }
    }

}

// Main loop - 100hz
static void fast_loop()
{
    // run low level rate controllers that only require IMU data
    run_rate_controllers();

    // write out the servo PWM values
    // ------------------------------
    set_servos_4();

    // IMU DCM Algorithm
    // --------------------
    read_AHRS();

    // reads all of the necessary trig functions for cameras, throttle, etc.
    // --------------------------------------------------------------------
    update_trig();

    // Inertial Nav
    // --------------------
    read_inertia();

    // optical flow
    // --------------------
#if OPTFLOW == ENABLED
    if(g.optflow_enabled) {
        update_optical_flow();
    }
#endif  // OPTFLOW == ENABLED

    // Read radio and 3-position switch on radio
    // -----------------------------------------
    read_radio();
    read_control_switch();

    // custom code/exceptions for flight modes
    // ---------------------------------------
    update_yaw_mode();
    update_roll_pitch_mode();

    // update targets to rate controllers
    update_rate_contoller_targets();

#ifdef USERHOOK_FASTLOOP
    USERHOOK_FASTLOOP
#endif

}

static void medium_loop()
{
    // This is the start of the medium (10 Hz) loop pieces
    // -----------------------------------------
    switch(medium_loopCounter) {

    // This case deals with the GPS and Compass
    //-----------------------------------------
    case 0:
        medium_loopCounter++;

#if HIL_MODE != HIL_MODE_ATTITUDE                                                               // don't execute in HIL mode
        if(g.compass_enabled) {
            if (compass.read()) {
                compass.null_offsets();
            }
        }
#endif

        // auto_trim - stores roll and pitch radio inputs to ahrs
        auto_trim();

        // record throttle output
        // ------------------------------
        throttle_integrator += g.rc_3.servo_out;
        break;

    // This case performs some navigation computations
    //------------------------------------------------
    case 1:
        medium_loopCounter++;
        read_receiver_rssi();
        break;

    // command processing
    //-------------------
    case 2:
        medium_loopCounter++;

        if(control_mode == TOY_A) {
            update_toy_throttle();

            if(throttle_mode == THROTTLE_AUTO) {
                update_toy_altitude();
            }
        }

        ap_system.alt_sensor_flag = true;
        break;

    // This case deals with sending high rate telemetry
    //-------------------------------------------------
    case 3:
        medium_loopCounter++;

        // perform next command
        // --------------------
        if(control_mode == AUTO) {
            if(ap.home_is_set && g.command_total > 1) {
                update_commands();
            }
        }

        if(motors.armed()) {
            if (g.log_bitmask & MASK_LOG_ATTITUDE_MED) {
                Log_Write_Attitude();
#if SECONDARY_DMP_ENABLED == ENABLED
                Log_Write_DMP();
#endif
            }

            if (g.log_bitmask & MASK_LOG_MOTORS)
                Log_Write_Motors();
        }
        break;

    // This case controls the slow loop
    //---------------------------------
    case 4:
        medium_loopCounter = 0;

        if (g.battery_monitoring != 0) {
            read_battery();
        }

        // Accel trims      = hold > 2 seconds
        // Throttle cruise  = switch less than 1 second
        // --------------------------------------------
        read_trim_switch();

        // Check for engine arming
        // -----------------------
        arm_motors();

#ifdef USERHOOK_MEDIUMLOOP
        USERHOOK_MEDIUMLOOP
#endif

#if COPTER_LEDS == ENABLED
        update_copter_leds();
#endif

        slow_loop();
        break;

    default:
        // this is just a catch all
        // ------------------------
        medium_loopCounter = 0;
        break;
    }
}

// stuff that happens at 50 hz
// ---------------------------
static void fifty_hz_loop()
{
    // read altitude sensors or estimate altitude
    // ------------------------------------------
    update_altitude_est();

    // Update the throttle ouput
    // -------------------------
    update_throttle_mode();

#if TOY_EDF == ENABLED
    edf_toy();
#endif

#ifdef USERHOOK_50HZLOOP
    USERHOOK_50HZLOOP
#endif


#if HIL_MODE != HIL_MODE_DISABLED && FRAME_CONFIG != HELI_FRAME
    // HIL for a copter needs very fast update of the servo values
    gcs_send_message(MSG_RADIO_OUT);
#endif

#if MOUNT == ENABLED
    // update camera mount's position
    camera_mount.update_mount_position();
#endif

#if MOUNT2 == ENABLED
    // update camera mount's position
    camera_mount2.update_mount_position();
#endif

#if CAMERA == ENABLED
    camera.trigger_pic_cleanup();
#endif

# if HIL_MODE == HIL_MODE_DISABLED
    if (g.log_bitmask & MASK_LOG_ATTITUDE_FAST && motors.armed()) {
        Log_Write_Attitude();
#if SECONDARY_DMP_ENABLED == ENABLED
        Log_Write_DMP();
#endif
    }

    if (g.log_bitmask & MASK_LOG_RAW && motors.armed())
        Log_Write_Raw();
#endif
}


static void slow_loop()
{

#if AP_LIMITS == ENABLED

    // Run the AP_Limits main loop
    limits_loop();

#endif // AP_LIMITS_ENABLED

    // This is the slow (3 1/3 Hz) loop pieces
    //----------------------------------------
    switch (slow_loopCounter) {
    case 0:
        slow_loopCounter++;
        superslow_loopCounter++;

        // record if the compass is healthy
        set_compass_healthy(compass.healthy);

        if(superslow_loopCounter > 1200) {
#if HIL_MODE != HIL_MODE_ATTITUDE
            if(g.rc_3.control_in == 0 && control_mode == STABILIZE && g.compass_enabled) {
                compass.save_offsets();
                superslow_loopCounter = 0;
            }
#endif
        }


        if(motors.armed()) {
            if (g.log_bitmask & MASK_LOG_ITERM)
                Log_Write_Iterm();
        }else{
            // check the user hasn't updated the frame orientation
            motors.set_frame_orientation(g.frame_orientation);
        }

        break;

    case 1:
        slow_loopCounter++;

#if MOUNT == ENABLED
        update_aux_servo_function(&g.rc_5, &g.rc_6, &g.rc_7, &g.rc_8, &g.rc_10, &g.rc_11);
#endif
        enable_aux_servos();

#if MOUNT == ENABLED
        camera_mount.update_mount_type();
#endif

#if MOUNT2 == ENABLED
        camera_mount2.update_mount_type();
#endif

#ifdef USERHOOK_SLOWLOOP
        USERHOOK_SLOWLOOP
#endif

        break;

    case 2:
        slow_loopCounter = 0;
        update_events();

        // blink if we are armed
        update_lights();

        if(g.radio_tuning > 0)
            tuning();

#if USB_MUX_PIN > 0
        check_usb_mux();
#endif
        break;

    default:
        slow_loopCounter = 0;
        break;
    }
}

#define AUTO_DISARMING_DELAY 25
// 1Hz loop
static void super_slow_loop()
{
    Log_Write_Data(DATA_AP_STATE, ap.value);

    if (g.log_bitmask & MASK_LOG_CUR && motors.armed())
        Log_Write_Current();

    // this function disarms the copter if it has been sitting on the ground for any moment of time greater than 25 seconds
    // but only of the control mode is manual
    if((control_mode <= ACRO) && (g.rc_3.control_in == 0)) {
        auto_disarming_counter++;

        if(auto_disarming_counter == AUTO_DISARMING_DELAY) {
            init_disarm_motors();
        }else if (auto_disarming_counter > AUTO_DISARMING_DELAY) {
            auto_disarming_counter = AUTO_DISARMING_DELAY + 1;
        }
    }else{
        auto_disarming_counter = 0;
    }

    // agmatthews - USERHOOKS
#ifdef USERHOOK_SUPERSLOWLOOP
    USERHOOK_SUPERSLOWLOOP
#endif
}

// called at 100hz but data from sensor only arrives at 20 Hz
#if OPTFLOW == ENABLED
static void update_optical_flow(void)
{
    static uint32_t last_of_update = 0;
    static int log_counter = 0;

    // if new data has arrived, process it
    if( optflow.last_update != last_of_update ) {
        last_of_update = optflow.last_update;
        optflow.update_position(ahrs.roll, ahrs.pitch, cos_yaw_x, sin_yaw_y, current_loc.alt);      // updates internal lon and lat with estimation based on optical flow

        // write to log at 5hz
        log_counter++;
        if( log_counter >= 4 ) {
            log_counter = 0;
            if (g.log_bitmask & MASK_LOG_OPTFLOW) {
                Log_Write_Optflow();
            }
        }
    }
}
#endif  // OPTFLOW == ENABLED

// called at 50hz
static void update_GPS(void)
{
    // A counter that is used to grab at least 10 reads before commiting the Home location
    static uint8_t ground_start_count  = 10;

    g_gps->update();
    update_GPS_light();

    set_gps_healthy(g_gps->status() == g_gps->GPS_OK);

    if (g_gps->new_data && g_gps->fix) {
        // clear new data flag
        g_gps->new_data = false;

        // check for duiplicate GPS messages
        if(last_gps_time != g_gps->time) {

            // for performance monitoring
            // --------------------------
            gps_fix_count++;

            if(ground_start_count > 1) {
                ground_start_count--;

            } else if (ground_start_count == 1) {

                // We countdown N number of good GPS fixes
                // so that the altitude is more accurate
                // -------------------------------------
                if (current_loc.lat == 0) {
                    ground_start_count = 5;

                }else{
                    if (g.compass_enabled) {
                        // Set compass declination automatically
                        compass.set_initial_location(g_gps->latitude, g_gps->longitude);
                    }
                    // save home to eeprom (we must have a good fix to have reached this point)
                    init_home();
                    ground_start_count = 0;
                }
            }

            if (g.log_bitmask & MASK_LOG_GPS && motors.armed()) {
                Log_Write_GPS();
            }

#if HIL_MODE == HIL_MODE_ATTITUDE                                                               // only execute in HIL mode
            ap_system.alt_sensor_flag = true;
#endif
        }

        // save GPS time so we don't get duplicate reads
        last_gps_time = g_gps->time;
    }
}

// set_yaw_mode - update yaw mode and initialise any variables required
bool set_yaw_mode(uint8_t new_yaw_mode)
{
    // boolean to ensure proper initialisation of throttle modes
    bool yaw_initialised = false;

    // return immediately if no change
    if( new_yaw_mode == yaw_mode ) {
        return true;
    }

    switch( new_yaw_mode ) {
        case YAW_HOLD:
        case YAW_ACRO:
            yaw_initialised = true;
            break;
        case YAW_LOOK_AT_NEXT_WP:
            if( ap.home_is_set ) {
                yaw_initialised = true;
            }
            break;
        case YAW_LOOK_AT_LOCATION:
            if( ap.home_is_set ) {
                // update bearing - assumes yaw_look_at_WP has been intialised before set_yaw_mode was called
                yaw_look_at_WP_bearing = get_bearing_cd(&current_loc, &yaw_look_at_WP);
                yaw_initialised = true;
            }
            break;
        case YAW_LOOK_AT_HEADING:
            yaw_initialised = true;
            break;
        case YAW_LOOK_AT_HOME:
            if( ap.home_is_set ) {
                yaw_initialised = true;
            }
            break;
        case YAW_TOY:
            yaw_initialised = true;
            break;
        case YAW_LOOK_AHEAD:
            if( ap.home_is_set ) {
                yaw_initialised = true;
            }
            break;
    }

    // if initialisation has been successful update the yaw mode
    if( yaw_initialised ) {
        yaw_mode = new_yaw_mode;
    }

    // return success or failure
    return yaw_initialised;
}

// update_yaw_mode - run high level yaw controllers
// 100hz update rate
void update_yaw_mode(void)
{
    switch(yaw_mode) {

    case YAW_HOLD:
        // heading hold at heading held in nav_yaw but allow input from pilot
        get_yaw_rate_stabilized_ef(g.rc_4.control_in);
        break;

    case YAW_ACRO:
        // pilot controlled yaw using rate controller
        if(g.axis_enabled) {
            get_yaw_rate_stabilized_ef(g.rc_4.control_in);
        }else{
            get_acro_yaw(g.rc_4.control_in);
        }
        break;

    case YAW_LOOK_AT_NEXT_WP:
        // point towards next waypoint (no pilot input accepted)
        // we don't use wp_bearing because we don't want the copter to turn too much during flight
        nav_yaw = get_yaw_slew(nav_yaw, original_wp_bearing, AUTO_YAW_SLEW_RATE);
        get_stabilize_yaw(nav_yaw);

        // if there is any pilot input, switch to YAW_HOLD mode for the next iteration
        if( g.rc_4.control_in != 0 ) {
            set_yaw_mode(YAW_HOLD);
        }
        break;

    case YAW_LOOK_AT_LOCATION:
        // point towards a location held in yaw_look_at_WP (no pilot input accepted)
        nav_yaw = get_yaw_slew(nav_yaw, yaw_look_at_WP_bearing, AUTO_YAW_SLEW_RATE);
        get_stabilize_yaw(nav_yaw);

        // if there is any pilot input, switch to YAW_HOLD mode for the next iteration
        if( g.rc_4.control_in != 0 ) {
            set_yaw_mode(YAW_HOLD);
        }
        break;

    case YAW_LOOK_AT_HOME:
        // keep heading always pointing at home with no pilot input allowed
        nav_yaw = get_yaw_slew(nav_yaw, home_bearing, AUTO_YAW_SLEW_RATE);
        get_stabilize_yaw(nav_yaw);

        // if there is any pilot input, switch to YAW_HOLD mode for the next iteration
        if( g.rc_4.control_in != 0 ) {
            set_yaw_mode(YAW_HOLD);
        }
        break;

    case YAW_LOOK_AT_HEADING:
        // keep heading pointing in the direction held in yaw_look_at_heading with no pilot input allowed
        nav_yaw = get_yaw_slew(nav_yaw, yaw_look_at_heading, yaw_look_at_heading_slew);
        get_stabilize_yaw(nav_yaw);
        break;

	case YAW_LOOK_AHEAD:
		// Commanded Yaw to automatically look ahead.
        get_look_ahead_yaw(g.rc_4.control_in);
        break;

#if TOY_LOOKUP == TOY_EXTERNAL_MIXER
    case YAW_TOY:
        // update to allow external roll/yaw mixing
        // keep heading always pointing at home with no pilot input allowed
        nav_yaw = get_yaw_slew(nav_yaw, home_bearing, AUTO_YAW_SLEW_RATE);
        get_stabilize_yaw(nav_yaw);
        break;
#endif
    }
}

// set_roll_pitch_mode - update roll/pitch mode and initialise any variables as required
bool set_roll_pitch_mode(uint8_t new_roll_pitch_mode)
{
    // boolean to ensure proper initialisation of throttle modes
    bool roll_pitch_initialised = false;

    // return immediately if no change
    if( new_roll_pitch_mode == roll_pitch_mode ) {
        return true;
    }

    switch( new_roll_pitch_mode ) {
        case ROLL_PITCH_STABLE:
        case ROLL_PITCH_ACRO:
        case ROLL_PITCH_AUTO:
        case ROLL_PITCH_STABLE_OF:
        case ROLL_PITCH_TOY:
        case ROLL_PITCH_LOITER_PR:
            roll_pitch_initialised = true;
            break;
    }

    // if initialisation has been successful update the yaw mode
    if( roll_pitch_initialised ) {
        roll_pitch_mode = new_roll_pitch_mode;
    }

    // return success or failure
    return roll_pitch_initialised;
}

// update_roll_pitch_mode - run high level roll and pitch controllers
// 100hz update rate
void update_roll_pitch_mode(void)
{
    if (ap.do_flip) {
        if(abs(g.rc_1.control_in) < 4000) {
            roll_flip();
            return;
        }else{
            // force an exit from the loop if we are not hands off sticks.
            ap.do_flip = false;
            Log_Write_Event(DATA_EXIT_FLIP);
        }
    }

    switch(roll_pitch_mode) {
    case ROLL_PITCH_ACRO:

#if FRAME_CONFIG == HELI_FRAME
		if(g.axis_enabled) {
            get_roll_rate_stabilized_ef(g.rc_1.control_in);
            get_pitch_rate_stabilized_ef(g.rc_2.control_in);
        }else{
            // ACRO does not get SIMPLE mode ability
            if (motors.flybar_mode == 1) {
                g.rc_1.servo_out = g.rc_1.control_in;
                g.rc_2.servo_out = g.rc_2.control_in;
            } else {
                get_acro_roll(g.rc_1.control_in);
                get_acro_pitch(g.rc_2.control_in);
            }
		}
#else  // !HELI_FRAME
		if(g.axis_enabled) {
            get_roll_rate_stabilized_ef(g.rc_1.control_in);
            get_pitch_rate_stabilized_ef(g.rc_2.control_in);
        }else{
            // ACRO does not get SIMPLE mode ability
            get_acro_roll(g.rc_1.control_in);
            get_acro_pitch(g.rc_2.control_in);
		}
#endif  // HELI_FRAME
        break;

    case ROLL_PITCH_STABLE:
        // apply SIMPLE mode transform
        if(ap.simple_mode && ap_system.new_radio_frame) {
            update_simple_mode();
        }

        control_roll            = g.rc_1.control_in;
        control_pitch           = g.rc_2.control_in;

        get_stabilize_roll(control_roll);
        get_stabilize_pitch(control_pitch);

        break;

    case ROLL_PITCH_AUTO:
        // apply SIMPLE mode transform
        if(ap.simple_mode && ap_system.new_radio_frame) {
            update_simple_mode();
        }
        // mix in user control with Nav control
        nav_roll                += constrain_int32(wrap_180(auto_roll  - nav_roll),  -g.auto_slew_rate.get(), g.auto_slew_rate.get());                 // 40 deg a second
        nav_pitch               += constrain_int32(wrap_180(auto_pitch - nav_pitch), -g.auto_slew_rate.get(), g.auto_slew_rate.get());                 // 40 deg a second

        control_roll            = g.rc_1.control_mix(nav_roll);
        control_pitch           = g.rc_2.control_mix(nav_pitch);

        get_stabilize_roll(control_roll);
        get_stabilize_pitch(control_pitch);
        break;

    case ROLL_PITCH_STABLE_OF:
        // apply SIMPLE mode transform
        if(ap.simple_mode && ap_system.new_radio_frame) {
            update_simple_mode();
        }

        control_roll            = g.rc_1.control_in;
        control_pitch           = g.rc_2.control_in;

        // mix in user control with optical flow
        get_stabilize_roll(get_of_roll(control_roll));
        get_stabilize_pitch(get_of_pitch(control_pitch));
        break;

    // THOR
    // a call out to the main toy logic
    case ROLL_PITCH_TOY:
        roll_pitch_toy();
        break;
        
    case ROLL_PITCH_LOITER_PR:
    
        // LOITER does not get SIMPLE mode ability
        
        nav_roll                += constrain(wrap_180(auto_roll  - nav_roll),  -g.auto_slew_rate.get(), g.auto_slew_rate.get());                 // 40 deg a second
        nav_pitch               += constrain(wrap_180(auto_pitch - nav_pitch), -g.auto_slew_rate.get(), g.auto_slew_rate.get());                 // 40 deg a second

        get_stabilize_roll(nav_roll);
        get_stabilize_pitch(nav_pitch);
        break;
    }

	#if FRAME_CONFIG != HELI_FRAME
    if(g.rc_3.control_in == 0 && control_mode <= ACRO) {
        reset_rate_I();
        reset_stability_I();
    }
	#endif //HELI_FRAME

    if(ap_system.new_radio_frame) {
        // clear new radio frame info
        ap_system.new_radio_frame = false;
    }
}

// new radio frame is used to make sure we only call this at 50hz
void update_simple_mode(void)
{
    static uint8_t simple_counter = 0;             // State machine counter for Simple Mode
    static float simple_sin_y=0, simple_cos_x=0;

    // used to manage state machine
    // which improves speed of function
    simple_counter++;

    int16_t delta = wrap_360(ahrs.yaw_sensor - initial_simple_bearing)/100;

    if (simple_counter == 1) {
        // roll
        simple_cos_x = sin(radians(90 - delta));

    }else if (simple_counter > 2) {
        // pitch
        simple_sin_y = cos(radians(90 - delta));
        simple_counter = 0;
    }

    // Rotate input by the initial bearing
    int16_t _roll   = g.rc_1.control_in * simple_cos_x + g.rc_2.control_in * simple_sin_y;
    int16_t _pitch  = -(g.rc_1.control_in * simple_sin_y - g.rc_2.control_in * simple_cos_x);

    g.rc_1.control_in = _roll;
    g.rc_2.control_in = _pitch;
}

// set_throttle_mode - sets the throttle mode and initialises any variables as required
bool set_throttle_mode( uint8_t new_throttle_mode )
{
    // boolean to ensure proper initialisation of throttle modes
    bool throttle_initialised = false;

    // return immediately if no change
    if( new_throttle_mode == throttle_mode ) {
        return true;
    }

    // initialise any variables required for the new throttle mode
    switch(new_throttle_mode) {
        case THROTTLE_MANUAL:
        case THROTTLE_MANUAL_TILT_COMPENSATED:
            throttle_accel_deactivate();                // this controller does not use accel based throttle controller
            throttle_initialised = true;
            break;

        case THROTTLE_ACCELERATION:                     // pilot inputs the desired acceleration
            if( g.throttle_accel_enabled ) {            // this throttle mode requires use of the accel based throttle controller
                throttle_initialised = true;
            }
            break;

        case THROTTLE_RATE:
        case THROTTLE_STABILIZED_RATE:
        case THROTTLE_DIRECT_ALT:
            throttle_initialised = true;
            break;

        case THROTTLE_HOLD:
        case THROTTLE_AUTO:
            set_new_altitude(current_loc.alt);          // by default hold the current altitude
            if ( throttle_mode < THROTTLE_HOLD ) {      // reset the alt hold I terms if previous throttle mode was manual
                reset_throttle_I();
            }
            throttle_initialised = true;
            break;

        case THROTTLE_LAND:
            set_land_complete(false);   // mark landing as incomplete
            land_detector = 0;          // A counter that goes up if our climb rate stalls out.
            set_new_altitude(0);        // Set a new target altitude
            throttle_initialised = true;
            break;

        case THROTTLE_SURFACE_TRACKING:
            if( g.sonar_enabled ) {
                set_new_altitude(current_loc.alt);          // by default hold the current altitude
                if ( throttle_mode < THROTTLE_HOLD ) {      // reset the alt hold I terms if previous throttle mode was manual
                    reset_throttle_I();
                }
                throttle_initialised = true;
            }
            // To-Do: handle the case where the sonar is not enabled
            break;

        default:
            // To-Do: log an error message to the dataflash or tlogs instead of printing to the serial port
            cliSerial->printf_P(PSTR("Unsupported throttle mode: %d!!"),new_throttle_mode);
            break;
    }

    // update the throttle mode
    if( throttle_initialised ) {
        throttle_mode = new_throttle_mode;

        // reset some variables used for logging
        desired_climb_rate = 0;
        nav_throttle = 0;
    }

    // return success or failure
    return throttle_initialised;
}

// update_throttle_mode - run high level throttle controllers
// 50 hz update rate
void update_throttle_mode(void)
{
    int16_t pilot_climb_rate;

    if(ap.do_flip)     // this is pretty bad but needed to flip in AP modes.
        return;

    // do not run throttle controllers if motors disarmed
    if( !motors.armed() ) {
        set_throttle_out(0, false);
        throttle_accel_deactivate();    // do not allow the accel based throttle to override our command
        return;
    }

#if FRAME_CONFIG == HELI_FRAME
	if (roll_pitch_mode == ROLL_PITCH_STABLE){
		motors.stab_throttle = true;
	} else {
		motors.stab_throttle = false;
	}
#endif // HELI_FRAME

    switch(throttle_mode) {

    case THROTTLE_MANUAL:
        // completely manual throttle
        if(g.rc_3.control_in <= 0){
            set_throttle_out(0, false);
        }else{
            // send pilot's output directly to motors
            set_throttle_out(g.rc_3.control_in, false);

            // update estimate of throttle cruise
			#if FRAME_CONFIG == HELI_FRAME
            update_throttle_cruise(motors.coll_out);
			#else
			update_throttle_cruise(g.rc_3.control_in);
			#endif  //HELI_FRAME


            // check if we've taken off yet
            if (!ap.takeoff_complete && motors.armed()) {
                if (g.rc_3.control_in > g.throttle_cruise) {
                    // we must be in the air by now
                    set_takeoff_complete(true);
                }
            }
        }
        break;

    case THROTTLE_MANUAL_TILT_COMPENSATED:
        // manual throttle but with angle boost
        if (g.rc_3.control_in <= 0) {
            set_throttle_out(0, false); // no need for angle boost with zero throttle
        }else{
            set_throttle_out(g.rc_3.control_in, true);

            // update estimate of throttle cruise
            #if FRAME_CONFIG == HELI_FRAME
            update_throttle_cruise(motors.coll_out);
			#else
			update_throttle_cruise(g.rc_3.control_in);
			#endif  //HELI_FRAME

            if (!ap.takeoff_complete && motors.armed()) {
                if (g.rc_3.control_in > g.throttle_cruise) {
                    // we must be in the air by now
                    set_takeoff_complete(true);
                }
            }
        }
        break;

    case THROTTLE_ACCELERATION:
        // pilot inputs the desired acceleration
        if(g.rc_3.control_in <= 0){
            set_throttle_out(0, false);
            throttle_accel_deactivate();    // do not allow the accel based throttle to override our command
        }else{
            int16_t desired_acceleration = get_pilot_desired_acceleration(g.rc_3.control_in);
            set_throttle_accel_target(desired_acceleration);
        }
        break;

    case THROTTLE_RATE:
        // pilot inputs the desired climb rate.  Note this is the unstabilized rate controller
        if(g.rc_3.control_in <= 0){
            set_throttle_out(0, false);
            throttle_accel_deactivate();    // do not allow the accel based throttle to override our command
        }else{
            pilot_climb_rate = get_pilot_desired_climb_rate(g.rc_3.control_in);
            get_throttle_rate(pilot_climb_rate);
        }
        break;

    case THROTTLE_STABILIZED_RATE:
        // pilot inputs the desired climb rate.  Note this is the stabilized rate controller
        if(g.rc_3.control_in <= 0){
            set_throttle_out(0, false);
            throttle_accel_deactivate();    // do not allow the accel based throttle to override our command
        }else{
            pilot_climb_rate = get_pilot_desired_climb_rate(g.rc_3.control_in);
            get_throttle_rate_stabilized(pilot_climb_rate);
        }
        break;

    case THROTTLE_DIRECT_ALT:
        // pilot inputs a desired altitude from 0 ~ 10 meters
        if(g.rc_3.control_in <= 0){
            set_throttle_out(0, false);
            throttle_accel_deactivate();    // do not allow the accel based throttle to override our command
        }else{
            // To-Do: this should update the global desired altitude variable next_WP.alt
            int32_t desired_alt = get_pilot_desired_direct_alt(g.rc_3.control_in);
            get_throttle_althold(desired_alt, g.auto_velocity_z_min, g.auto_velocity_z_max);
        }
        break;

    case THROTTLE_HOLD:
        // alt hold plus pilot input of climb rate
        pilot_climb_rate = get_pilot_desired_climb_rate(g.rc_3.control_in);
        get_throttle_rate_stabilized(pilot_climb_rate);
        break;

    case THROTTLE_AUTO:
        // auto pilot altitude controller with target altitude held in next_WP.alt
        if(motors.auto_armed() == true) {
            get_throttle_althold(next_WP.alt, g.auto_velocity_z_min, g.auto_velocity_z_max);
        }
        break;

    case THROTTLE_LAND:
        // landing throttle controller
        get_throttle_land();
        break;

    case THROTTLE_SURFACE_TRACKING:
        // surface tracking with sonar or other rangefinder plus pilot input of climb rate
        pilot_climb_rate = get_pilot_desired_climb_rate(g.rc_3.control_in);
        if( sonar_alt_ok ) {
            // if sonar is ok, use surface tracking
            get_throttle_surface_tracking(pilot_climb_rate);
        }else{
            // if no sonar fall back stabilize rate controller
            get_throttle_rate_stabilized(pilot_climb_rate);
        }
        break;
    }
}

static void read_AHRS(void)
{
    // Perform IMU calculations and get attitude info
    //-----------------------------------------------
#if HIL_MODE != HIL_MODE_DISABLED
    // update hil before ahrs update
    gcs_update();
#endif

    ahrs.update();
    omega = ins.get_gyro();

#if SECONDARY_DMP_ENABLED == ENABLED
    ahrs2.update();
#endif
}

static void update_trig(void){
    Vector2f yawvector;
    Matrix3f temp   = ahrs.get_dcm_matrix();

    yawvector.x     = temp.a.x;     // sin
    yawvector.y     = temp.b.x;         // cos
    yawvector.normalize();

    cos_pitch_x     = safe_sqrt(1 - (temp.c.x * temp.c.x));     // level = 1
    cos_roll_x      = temp.c.z / cos_pitch_x;                       // level = 1

    cos_pitch_x     = constrain(cos_pitch_x, 0, 1.0);
    // this relies on constrain() of infinity doing the right thing,
    // which it does do in avr-libc
    cos_roll_x      = constrain(cos_roll_x, -1.0, 1.0);

    sin_yaw_y       = yawvector.x;                                              // 1y = north
    cos_yaw_x       = yawvector.y;                                              // 0x = north

    // added to convert earth frame to body frame for rate controllers
    sin_pitch       = -temp.c.x;
    sin_roll        = temp.c.y / cos_pitch_x;

    //flat:
    // 0 ° = cos_yaw:  0.00, sin_yaw:  1.00,
    // 90° = cos_yaw:  1.00, sin_yaw:  0.00,
    // 180 = cos_yaw:  0.00, sin_yaw: -1.00,
    // 270 = cos_yaw: -1.00, sin_yaw:  0.00,
}

// updated at 10hz
static void update_altitude()
{
    int32_t old_baro_alt    = baro_alt;
    int16_t old_sonar_alt   = sonar_alt;

#if HIL_MODE == HIL_MODE_ATTITUDE
    // we are in the SIM, fake out the baro and Sonar
    int16_t fake_relative_alt = g_gps->altitude - gps_base_alt;
    baro_alt                = fake_relative_alt;
    baro_rate               = (baro_alt - old_baro_alt) * 5;             // 5hz
    if(g.sonar_enabled) {
        sonar_alt           = fake_relative_alt;
        sonar_rate          = baro_rate;
    }
    current_loc.alt = baro_alt;
    climb_rate_actual = baro_rate;
#else
    // read in actual baro altitude
    baro_alt            = read_barometer();

    // calc baro based vertical velocity
    int16_t temp		= (baro_alt - old_baro_alt) * 10;
    baro_rate           = (temp + baro_rate) >> 1;
    baro_rate			= constrain(baro_rate, -500, 500);

    // read in sonar altitude and calculate sonar rate
    if(g.sonar_enabled) {
        sonar_alt       = read_sonar();
        sonar_rate      = (sonar_alt - old_sonar_alt) * 10;
        sonar_rate      = constrain(sonar_rate, -150, 150);
    }

    // Note: with inertial nav, alt and rate are pulled from the inav lib at 50hz in update_altitude_est function
    // so none of the below is required
# if INERTIAL_NAV_Z != ENABLED
    // if no sonar set current alt to baro alt
    if(!g.sonar_enabled) {
        // NO Sonar case
        current_loc.alt = baro_alt;
        climb_rate_actual = baro_rate;
    }else{
        // Blend barometer and sonar data together
        float scale;
        if(baro_alt < 800) {
            scale = (float)(sonar_alt - 400) / 200.0;
            scale = constrain(scale, 0.0, 1.0);
            // solve for a blended altitude
            current_loc.alt = ((float)sonar_alt * (1.0 - scale)) + ((float)baro_alt * scale);

            // solve for a blended climb_rate
            climb_rate_actual = ((float)sonar_rate * (1.0 - scale)) + (float)baro_rate * scale;

        }else{
            // we must be higher than sonar (>800), don't get tricked by bad sonar reads
            current_loc.alt = baro_alt;
            // dont blend, go straight baro
            climb_rate_actual       = baro_rate;
        }
    }
    // climb_rate_error is used to spread the change in climb rate across the next 5 samples
    climb_rate_error = (climb_rate_actual - climb_rate) / 5;
# endif // INERTIAL_NAV_Z != ENABLED
#endif  // HIL_MODE == HIL_MODE_ATTITUDE

    // update the target altitude
    verify_altitude();
}

static void update_altitude_est()
{
#if INERTIAL_NAV_Z == ENABLED
    // with inertial nav we can update the altitude and climb rate at 50hz
    current_loc.alt = inertial_nav.get_altitude();
    climb_rate = inertial_nav.get_velocity_z();

    // update baro and sonar alt and climb rate just for logging purposes
    // To-Do: remove alt_sensor_flag and move update_altitude to be called from 10hz loop
    if(ap_system.alt_sensor_flag) {
        ap_system.alt_sensor_flag = false;
        update_altitude();
        if(g.log_bitmask & MASK_LOG_CTUN && motors.armed()) {
            Log_Write_Control_Tuning();
        }
    }
#else
    if(ap_system.alt_sensor_flag) {
        update_altitude();
        ap_system.alt_sensor_flag = false;

        if(g.log_bitmask & MASK_LOG_CTUN && motors.armed()) {
            Log_Write_Control_Tuning();
        }
    }else{
        // simple dithering of climb rate
        climb_rate += climb_rate_error;
        current_loc.alt += (climb_rate / 50);
    }
#endif
}

static void tuning(){
    tuning_value = (float)g.rc_6.control_in / 1000.0;
    g.rc_6.set_range(g.radio_tuning_low,g.radio_tuning_high);                   // 0 to 1

    switch(g.radio_tuning) {

    case CH6_RATE_KD:
        g.pid_rate_roll.kD(tuning_value);
        g.pid_rate_pitch.kD(tuning_value);
        break;

    case CH6_STABILIZE_KP:
        g.pi_stabilize_roll.kP(tuning_value);
        g.pi_stabilize_pitch.kP(tuning_value);
        break;

    case CH6_STABILIZE_KI:
        g.pi_stabilize_roll.kI(tuning_value);
        g.pi_stabilize_pitch.kI(tuning_value);
        break;

    case CH6_ACRO_KP:
        g.acro_p = tuning_value;
        break;

    case CH6_RATE_KP:
        g.pid_rate_roll.kP(tuning_value);
        g.pid_rate_pitch.kP(tuning_value);
        break;

    case CH6_RATE_KI:
        g.pid_rate_roll.kI(tuning_value);
        g.pid_rate_pitch.kI(tuning_value);
        break;

    case CH6_YAW_KP:
        g.pi_stabilize_yaw.kP(tuning_value);
        break;

    case CH6_YAW_KI:
        g.pi_stabilize_yaw.kI(tuning_value);
        break;

    case CH6_YAW_RATE_KP:
        g.pid_rate_yaw.kP(tuning_value);
        break;

    case CH6_YAW_RATE_KD:
        g.pid_rate_yaw.kD(tuning_value);
        break;

    case CH6_THROTTLE_KP:
        g.pid_throttle.kP(tuning_value);
        break;

    case CH6_THROTTLE_KI:
        g.pid_throttle.kI(tuning_value);
        break;

    case CH6_THROTTLE_KD:
        g.pid_throttle.kD(tuning_value);
        break;

    case CH6_TOP_BOTTOM_RATIO:
        motors.top_bottom_ratio = tuning_value;
        break;

    case CH6_RELAY:
        if (g.rc_6.control_in > 525) relay.on();
        if (g.rc_6.control_in < 475) relay.off();
        break;

    case CH6_TRAVERSE_SPEED:
        g.waypoint_speed_max = g.rc_6.control_in;
        break;

    case CH6_LOITER_KP:
        g.pi_loiter_lat.kP(tuning_value);
        g.pi_loiter_lon.kP(tuning_value);
        break;

    case CH6_LOITER_KI:
        g.pi_loiter_lat.kI(tuning_value);
        g.pi_loiter_lon.kI(tuning_value);
        break;

    case CH6_NAV_KP:
        g.pid_nav_lat.kP(tuning_value);
        g.pid_nav_lon.kP(tuning_value);
        break;

    case CH6_LOITER_RATE_KP:
        g.pid_loiter_rate_lon.kP(tuning_value);
        g.pid_loiter_rate_lat.kP(tuning_value);
        break;

    case CH6_LOITER_RATE_KI:
        g.pid_loiter_rate_lon.kI(tuning_value);
        g.pid_loiter_rate_lat.kI(tuning_value);
        break;

    case CH6_LOITER_RATE_KD:
        g.pid_loiter_rate_lon.kD(tuning_value);
        g.pid_loiter_rate_lat.kD(tuning_value);
        break;

    case CH6_NAV_KI:
        g.pid_nav_lat.kI(tuning_value);
        g.pid_nav_lon.kI(tuning_value);
        break;

#if FRAME_CONFIG == HELI_FRAME
    case CH6_HELI_EXTERNAL_GYRO:
        motors.ext_gyro_gain = tuning_value;
        break;
#endif

    case CH6_THR_HOLD_KP:
        g.pi_alt_hold.kP(tuning_value);
        break;

    case CH6_OPTFLOW_KP:
        g.pid_optflow_roll.kP(tuning_value);
        g.pid_optflow_pitch.kP(tuning_value);
        break;

    case CH6_OPTFLOW_KI:
        g.pid_optflow_roll.kI(tuning_value);
        g.pid_optflow_pitch.kI(tuning_value);
        break;

    case CH6_OPTFLOW_KD:
        g.pid_optflow_roll.kD(tuning_value);
        g.pid_optflow_pitch.kD(tuning_value);
        break;

#if HIL_MODE != HIL_MODE_ATTITUDE                                       // do not allow modifying _kp or _kp_yaw gains in HIL mode
    case CH6_AHRS_YAW_KP:
        ahrs._kp_yaw.set(tuning_value);
        break;

    case CH6_AHRS_KP:
        ahrs._kp.set(tuning_value);
        break;
#endif

    case CH6_INAV_TC:
#if INERTIAL_NAV_XY == ENABLED
        inertial_nav.set_time_constant_xy(tuning_value);
#endif
#if INERTIAL_NAV_Z == ENABLED
        inertial_nav.set_time_constant_z(tuning_value);
#endif
        break;

    case CH6_THR_ACCEL_KP:
        g.pid_throttle_accel.kP(tuning_value);
        break;

    case CH6_THR_ACCEL_KI:
        g.pid_throttle_accel.kI(tuning_value);
        break;

    case CH6_THR_ACCEL_KD:
        g.pid_throttle_accel.kD(tuning_value);
        break;
    }
}

AP_HAL_MAIN();