Subversion Repositories FlightCtrl

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Copyright (c) 04.2007 Holger Buss
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#include <stdlib.h>
#include <avr/io.h>
#include "eeprom.h"
#include "flight.h"

// Only for debug. Remove.
#include "analog.h"

// Necessary for external control and motor test
#include "uart0.h"
#include "twimaster.h"
#include "attitude.h"
#include "controlMixer.h"
#ifdef USE_MK3MAG
#include "gps.h"
#endif

#define CHECK_MIN_MAX(value, min, max) {if(value < min) value = min; else if(value > max) value = max;}

// TODO: These are no longer maintained, just left at 0. The original implementation just summed the acc.
// value to them every 2 ms. No filtering or anything. Just a case for an eventual overflow?? Hey???
int16_t naviAccPitch = 0, naviAccRoll = 0, naviCntAcc = 0;

// MK flags
uint16_t isFlying = 0;
volatile uint8_t MKFlags = 0;

uint8_t gyroPFactor, gyroIFactor;       // the PD factors for the attitude control
uint8_t yawRatePFactor, yawRateIFactor; // the PD factors for the yaw control

// Some integral weight constant...
uint16_t Ki = 10300 / 33;

uint8_t RequiredMotors = 0;

// No support for altitude control right
// int16_t SetPointHeight = 0;

/************************************************************************/
/*  Filter for motor value smoothing (necessary???)                     */
/************************************************************************/
int16_t motorFilter(int16_t newvalue, int16_t oldvalue) {
  switch(dynamicParams.UserParams[5]) {
  case 0:
    return newvalue;
  case 1:
    return (oldvalue + newvalue) / 2;  
  case 2:
    if(newvalue > oldvalue)
      return (1 * (int16_t)oldvalue + newvalue) / 2;  //mean of old and new
    else       
      return newvalue - (oldvalue - newvalue) * 1; // 2 * new - old
  case 3:
    if(newvalue < oldvalue)
      return (1 * (int16_t)oldvalue + newvalue) / 2;  //mean of old and new
    else       
      return newvalue - (oldvalue - newvalue) * 1; // 2 * new - old
  default: return newvalue;
  }
}

/************************************************************************/
/*  Neutral Readings                                                    */
/************************************************************************/
void flight_setNeutral() {
  // GPSStickPitch = 0;
  // GPSStickRoll = 0;

  MKFlags |= MKFLAG_CALIBRATE;

  // not really used here any more.
  dynamicParams.KalmanK = -1;
  dynamicParams.KalmanMaxDrift = 0;
  dynamicParams.KalmanMaxFusion = 32;

  controlMixer_initVariables();

  // TODO: Move off.
  // RC_Quality = 100;
}

/************************************************************************/
/*  Transmit Motor Data via I2C                                         */
/************************************************************************/
void sendMotorData(void) {
  uint8_t i;
  if(!(MKFlags & MKFLAG_MOTOR_RUN)) {
    // If pilot has not started the engines....
    MKFlags &= ~(MKFLAG_FLY | MKFLAG_START); // clear flag FLY and START if motors are off
    for(i = 0; i < MAX_MOTORS; i++) {
      // and if we are not in motor test mode, cut throttle on all motors.
      if(!motorTestActive) Motor[i].SetPoint = 0;
      else                 Motor[i].SetPoint = motorTest[i];
    }
    if(motorTestActive) motorTestActive--;
  }
 
  DebugOut.Analog[12] = Motor[0].SetPoint; // Front
  DebugOut.Analog[13] = Motor[1].SetPoint; // Rear
  DebugOut.Analog[14] = Motor[3].SetPoint; // Left
  DebugOut.Analog[15] = Motor[2].SetPoint; // Right
  // Start I2C Interrupt Mode
  I2C_Start(TWI_STATE_MOTOR_TX);
}

void setFlightParameters(uint8_t _Ki, uint8_t _gyroPFactor, uint8_t _gyroIFactor, uint8_t _yawPFactor, uint8_t _yawIFactor) {
  Ki = 10300 / _Ki;
  gyroPFactor = _gyroPFactor;
  gyroIFactor = _gyroIFactor;
  yawRatePFactor = _yawPFactor;
  yawRateIFactor = _yawIFactor;
}

void setNormalFlightParameters(void) {
  if(staticParams.GlobalConfig & CFG_HEADING_HOLD) gyroIFactor = 0;
  else gyroIFactor = dynamicParams.GyroI;

  setFlightParameters(dynamicParams.IFactor + 1,
                      dynamicParams.GyroP + 10,
                      staticParams.GlobalConfig & CFG_HEADING_HOLD ? dynamicParams.GyroI : 0,
                      dynamicParams.GyroP + 10,
                      dynamicParams.UserParams[6]
                      );
}

void setStableFlightParameters(void) {
  setFlightParameters(33, 90, 120, 90, 120);
}

void handleCommands(uint8_t command, uint8_t isCommandRepeated) {
    if(!(MKFlags & MKFLAG_MOTOR_RUN)) {
      if (command == COMMAND_GYROCAL && !isCommandRepeated) {
        // Run gyro calibration but do not repeat it.
        GRN_OFF;
       
        // TODO: out of here. Anyway, MKFLAG_MOTOR_RUN is cleared. Not enough?
        // isFlying = 0;
        // check roll/pitch stick position
        // if pitch stick is top or roll stick is left or right --> change parameter setting
        // according to roll/pitch stick position
       
        uint8_t setting = controlMixer_getArgument();
       
        if ((setting > 0 && setting < 6) || setting == 9) {
          // Gyro calinbration, with or without selecting a new parameter-set.
          if(setting > 0 && setting < 6) {
            // A valid parameter-set (1..5) was chosen - use it.
            setActiveParamSet(setting);
          }
          ParamSet_ReadFromEEProm(getActiveParamSet());
          attitude_setNeutral();
          flight_setNeutral();
          // Right stick is centered; calibrate it to zero (hmm strictly does not belong here).
          controlMixer_setNeutral(setting == 9); // Calibrate right stick neutral position.
          beepNumber(getActiveParamSet());
        } else if(staticParams.GlobalConfig & (CFG_COMPASS_ACTIVE | CFG_GPS_ACTIVE) && setting == 7) {
          // If right stick is centered and down
          compassCalState = 1;
          beep(1000);
        }
      }
     
      // save the ACC neutral setting to eeprom
      else  {
        if(command == COMMAND_ACCCAL && !isCommandRepeated) {
          // Run gyro and acc. meter calibration but do not repeat it.
          GRN_OFF;
          analog_calibrateAcc();
          attitude_setNeutral();
          flight_setNeutral();
          controlMixer_setNeutral(1); // Calibrate right stick neutral position.
          beepNumber(getActiveParamSet());
        }
      }
    } // end !MOTOR_RUN condition.
    if (command == COMMAND_START) {
      isFlying = 1; // TODO: Really????
      // if (!controlMixer_isCommandRepeated()) {
      // attitude_startDynamicCalibration(); // Try sense the effect of the motors on sensors.
      MKFlags |= (MKFLAG_MOTOR_RUN | MKFLAG_START); // set flag RUN and START. TODO: Is that START flag used at all???
      // } else { // Pilot is holding stick, ever after motor start. Continue to sense the effect of the motors on sensors.
      // attitude_continueDynamicCalibration();
      // setPointYaw = 0;
      // IPartPitch = 0;
      // IPartRoll = 0;
      // }
    } else if (command == COMMAND_STOP) {
      isFlying = 0;
      MKFlags &= ~(MKFLAG_MOTOR_RUN);
    }
}

/************************************************************************/
/*  Main Flight Control                                                 */
/************************************************************************/
void flight_control(void) {
  int16_t tmp_int;
    // Mixer Fractions that are combined for Motor Control
  int16_t yawTerm, throttleTerm, pitchTerm, rollTerm;

  // PID controller variables
  int16_t PDPartPitch, PDPartRoll, PDPartYaw, PPartPitch, PPartRoll;
  static int32_t IPartPitch = 0, IPartRoll = 0;

  static int32_t setPointYaw = 0;

  // Removed. Too complicated, and apparently not necessary with MEMS gyros anyway.
  // static int32_t IntegralGyroPitchError = 0, IntegralGyroRollError = 0;
  // static int32_t CorrectionPitch, CorrectionRoll;

  static uint16_t emergencyFlightTime;

  // No support for altitude control right now.
  // static uint8_t HeightControlActive = 0;
  // static int16_t HeightControlGas = 0;

  static int8_t debugDataTimer = 0;

  // High resolution motor values for smoothing of PID motor outputs
  static int16_t motorFilters[MAX_MOTORS];

  uint8_t i;

  // Fire the main flight attitude calculation, including integration of angles.
  calculateFlightAttitude();
  GRN_ON;

  /*
   * TODO: update should: Set the stick variables if good signal, set them to zero if bad.
   * Set variables also.
   */
  controlMixer_update();

  throttleTerm = controlThrottle;
  if(throttleTerm < staticParams.MinThrottle + 10) throttleTerm = staticParams.MinThrottle + 10;

  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  // RC-signal is bad
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  if(controlMixer_getSignalQuality() <= SIGNAL_BAD) {           // the rc-frame signal is not reveived or noisy
    RED_ON;
    beepRCAlarm();
   
    if(emergencyFlightTime) {
      // continue emergency flight
      emergencyFlightTime--;
      if(isFlying > 1000) {                    
        // We're probably still flying. Descend slowly.
        throttleTerm = staticParams.EmergencyGas;  // Set emergency throttle
        MKFlags |= (MKFLAG_EMERGENCY_LANDING);     // Set flag for emergency landing
        setStableFlightParameters();
      } else {
        MKFlags &= ~(MKFLAG_MOTOR_RUN);            // Probably not flying, and bad R/C signal. Kill motors.
      }
    } else {
      // end emergency flight (just cut the motors???)
      MKFlags &= ~(MKFLAG_MOTOR_RUN | MKFLAG_EMERGENCY_LANDING);
    }
  } else {
    // signal is acceptable
    if(controlMixer_getSignalQuality() > SIGNAL_BAD) {
      // Reset emergency landing control variables.
      MKFlags &= ~(MKFLAG_EMERGENCY_LANDING);  // clear flag for emergency landing
      // The time is in whole seconds.
      emergencyFlightTime = staticParams.EmergencyGasDuration * 488;
    }

    // If some throttle is given, and the motor-run flag is on, increase the probability that we are flying.
    if(throttleTerm > 40 && (MKFlags & MKFLAG_MOTOR_RUN)) {
      // increment flight-time counter until overflow.
      if(isFlying != 0xFFFF) isFlying++;
    } else
      /*
       * When standing on the ground, do not apply I controls and zero the yaw stick.
       * Probably to avoid integration effects that will cause the copter to spin
       * or flip when taking off.
       * TODO: What was the value of IPartPitch? At 1st run of this, it's 0 already.
       */
      if(isFlying < 256) {
        IPartPitch = 0;
        IPartRoll = 0;
        // TODO: Don't stomp on other modules' variables!!!
        controlYaw = 0;
        if(isFlying == 250) {
          updateCompassCourse = 1;
          yawAngle = 0;
          setPointYaw = 0;
        }
      } else {
        // DebugOut.Digital[1] = 0;
        // Set fly flag. TODO: Hmmm what can we trust - the isFlying counter or the flag?
        // Answer: The counter. The flag is not read from anywhere anyway... except the NC maybe.
        MKFlags |= (MKFLAG_FLY);
      }
   
    /*
     * Get the current command (start/stop motors, calibrate), if any.
     */
    handleCommands(controlMixer_getCommand(), controlMixer_isCommandRepeated());

    // if(controlMixer_getSignalQuality() >= SIGNAL_GOOD) {
    setNormalFlightParameters();
    // }
  }
   
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  // in case of emergency landing
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  // set all inputs to save values
  /*
   * Looping the H&I way basically is just a matter of turning off attitude angle measurement
   * by integration (because 300 deg/s gyros are too slow) and turning down the throttle.
   * This is the latter.
   */
  if(looping) {
    if(throttleTerm > staticParams.LoopGasLimit) throttleTerm = staticParams.LoopGasLimit;
  }
 
  /*
   * Here is a dynamic calibration experiment: Adjust integrals and gyro offsets if the pilot appears to be always
   * pushing of pulling on the pitch or roll stick.
   */
  /*
    if(ADCycleCount >= dynamicParams.UserParam2 * 10) {
    // This algo works OK on the desk but it is a little sluggish and it oscillates.
    // It does not very effectively cancel drift because of dynamics.
   
    minStickForAutoCal = dynamicParams.UserParam3 * 10;
    maxStickForAutoCal = dynamicParams.UserParam4 * 10;
   
    // If not already corrected to the limit, and dynamic calibration is enabled:
    if (abs(dynamicOffsetPitch - savedDynamicOffsetPitch) < dynamicParams.UserParam1 && !dynamicParams.UserParam6) {
    // The pilot pushes on the stick, the integral is > 0, and the gyro val is > 0. Looks like a value-too-high case, so increase the offset.
    if (filteredHiResPitchGyro > dynamicOffsetPitch && pitchAngle > 0 && maxStickPitch >= minStickForAutoCal && maxStickPitch <= maxStickForAutoCal) {
    dynamicOffsetPitch += (int8_t)(dynamicParams.UserParam7 - 128); // (adding something seems right...)
    pitchAngle = (pitchAngle * (int32_t)dynamicParams.UserParam5) / 100L;
    } else if (filteredHiResPitchGyro < dynamicOffsetPitch && pitchAngle < 0 && maxStickPitch <= -minStickForAutoCal && maxStickPitch >= -maxStickForAutoCal) {
    dynamicOffsetPitch -= (int8_t)(dynamicParams.UserParam7 - 128); // (subtracting something seems right...)
    pitchAngle = (pitchAngle * (int32_t)dynamicParams.UserParam5) / 100L;
    }
    }
   
    // If not already corrected to the limit, and dynamic calibration is enabled:
    if (abs(dynamicOffsetRoll - savedDynamicOffsetRoll) <= dynamicParams.UserParam1 && !dynamicParams.UserParam6) {
    if (filteredHiResRollGyro > dynamicOffsetRoll && rollAngle > 0 && maxStickRoll >= minStickForAutoCal && maxStickRoll <= maxStickForAutoCal) {
    dynamicOffsetRoll += (int8_t)(dynamicParams.UserParam8 - 128);
    rollAngle = (rollAngle * (int32_t)dynamicParams.UserParam5) / 100L;
    } else if (filteredHiResRollGyro < dynamicOffsetRoll && rollAngle < 0 && maxStickRoll <= -minStickForAutoCal && maxStickRoll >= -maxStickForAutoCal) {
    dynamicOffsetRoll -= (int8_t)(dynamicParams.UserParam8 - 128);
    rollAngle = (rollAngle * (int32_t)dynamicParams.UserParam5) / 100L;
    }
    }
    ADCycleCount = 0;
    }
  */
 
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  //  Yawing
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  if(abs(controlYaw) > 4 * staticParams.StickYawP) { // yaw stick is activated
    badCompassHeading = 1000;
    if(!(staticParams.GlobalConfig & CFG_COMPASS_FIX)) {
      updateCompassCourse = 1;
    }
  }
 
  setPointYaw = controlYaw;

  // trimm drift of ReadingIntegralGyroYaw with SetPointYaw(StickYaw)
  // TODO: We want NO feedback of control related stuff to the attitude related stuff.
  yawAngle -= tmp_int;

  // limit the effect
  CHECK_MIN_MAX(yawAngle, -50000, 50000)

    // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    //  Compass
    // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    // compass code is used if Compass option is selected

    /*
    if(staticParams.GlobalConfig & (CFG_COMPASS_ACTIVE|CFG_GPS_ACTIVE)) {
      updateCompass();
    }
    */

#if defined (USE_MK3MAG)
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  //  GPS
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  if(staticParams.GlobalConfig & CFG_GPS_ACTIVE) {
    GPS_Main();
    MKFlags &= ~(MKFLAG_CALIBRATE | MKFLAG_START);
  }
  else {
    // GPSStickPitch = 0;
    // GPSStickRoll = 0;
  }
#endif

  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  //  calculate control feedback from angle (gyro integral) and agular velocity (gyro signal)
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  // The P-part is actually the I-part...
  if(looping & LOOPING_PITCH_AXIS) {
    PPartPitch = 0;
  } else {
    // TODO: Where do the 44000 come from???
    PPartPitch = (pitchAngle * gyroIFactor) / (44000 / STICK_GAIN); // P-Part - Proportional to Integral
    // PPartPitch = IntegralNickMalFaktor in H&I code.
  }

  // Now blend in the P-part - proportional to the Differential of the integral = the gyro value.
  PDPartPitch = PPartPitch + (int32_t)((int32_t)pitchRate_PID * gyroPFactor) / (256L / STICK_GAIN)
    + (pitchDifferential * dynamicParams.GyroD) / 16;
  // = MesswertNick in H&I code
 
  // The P-part is actually the I-part...
  if(looping & LOOPING_ROLL_AXIS) {
    PPartRoll = 0;
  } else {
    PPartRoll = (rollAngle * gyroIFactor) / (44000 / STICK_GAIN); // P-Part - Proportional to Integral
  }
 
  // Now blend in the P-part - proportional to the Differential of the integral = the gyro value.
  PDPartRoll = PPartRoll + (int32_t)((int32_t)rollRate_PID * gyroPFactor) / (256L / STICK_GAIN)
    + (rollDifferential * dynamicParams.GyroD) / 16;
 
  PDPartYaw =  (int32_t)(yawRate * 2 * (int32_t)yawRatePFactor) / (256L / STICK_GAIN) + (int32_t)(yawAngle * yawRateIFactor) / (2 * (44000 / STICK_GAIN));
 
  // limit control feedback
#define SENSOR_LIMIT  (4096 * 4)
  CHECK_MIN_MAX(PDPartPitch, -SENSOR_LIMIT, SENSOR_LIMIT);
  CHECK_MIN_MAX(PDPartRoll, -SENSOR_LIMIT, SENSOR_LIMIT);
  CHECK_MIN_MAX(PDPartYaw,  -SENSOR_LIMIT, SENSOR_LIMIT);
 
  /*
   * Compose throttle term.
   * If a Bl-Ctrl is missing, prevent takeoff.
   */
  if(missingMotor) {
    // if we are in the lift off condition. Hmmmmmm when is throttleTerm == 0 anyway???
    if((isFlying > 1) && (isFlying < 50) && (throttleTerm > 0))
      isFlying = 1; // keep within lift off condition
    throttleTerm = staticParams.MinThrottle; // reduce gas to min to avoid lift of
  }

  /*
   * Height control was here.
   */

  if(throttleTerm > staticParams.MaxThrottle - 20) throttleTerm = (staticParams.MaxThrottle - 20);
  throttleTerm *= STICK_GAIN;

  /*
   * Compose yaw term.
   */
#define MIN_YAWGAS (40 * STICK_GAIN)  // yaw also below this gas value
  yawTerm = PDPartYaw - setPointYaw * STICK_GAIN;     // yaw controller
  // limit yawTerm
  if(throttleTerm > MIN_YAWGAS) {
    CHECK_MIN_MAX(yawTerm, - (throttleTerm / 2), (throttleTerm / 2));
  } else {
    CHECK_MIN_MAX(yawTerm, - (MIN_YAWGAS / 2), (MIN_YAWGAS / 2));
  }
 
  tmp_int = staticParams.MaxThrottle * STICK_GAIN;
  CHECK_MIN_MAX(yawTerm, -(tmp_int - throttleTerm), (tmp_int - throttleTerm));

  /*
   * Compose pitch and roll terms. This is finally where the sticks come into play.
   */
  if(gyroIFactor) {
    // Integration mode: Integrate (angle - stick) = the difference between angle and stick pos.
    // That means: Holding the stick a little forward will, at constant flight attitude, cause this to grow (decline??) over time.
    // TODO: Find out why this seems to be proportional to stick position - not integrating it at all.
    IPartPitch += PPartPitch - controlPitch; // Integrate difference between P part (the angle) and the stick pos.
    IPartRoll += PPartRoll - controlRoll;    // I-part for attitude control OK
  } else {
    // "HH" mode: Integrate (rate - stick) = the difference between rotation rate and stick pos.
    IPartPitch += PDPartPitch - controlPitch; // With gyroIFactor == 0, PDPart is really just a D-part. Integrate D-part (the rot. rate) and the stick pos.
    IPartRoll += PDPartRoll - controlRoll;    // With gyroIFactor == 0, PDPart is really just a D-part. Integrate D-part (the rot. rate) and the stick pos.
  }
 
  // TODO: From which planet comes the 16000?
  CHECK_MIN_MAX(IPartPitch, -(STICK_GAIN * 16000L), (STICK_GAIN * 16000L));

  // Add (P, D) parts minus stick pos. to the scaled-down I part.
  pitchTerm = PDPartPitch - controlPitch + IPartPitch / Ki;    // PID-controller for pitch

  CHECK_MIN_MAX(IPartRoll, -(STICK_GAIN * 16000L), (STICK_GAIN * 16000L));
  rollTerm = PDPartRoll - controlRoll + IPartRoll / Ki;  // PID-controller for roll

  /*
   * Apply "dynamic stability" - that is: Limit pitch and roll terms to a growing function of throttle and yaw(!).
   * The higher the dynamic stability parameter, the wider the bounds. 64 seems to be a kind of unity
   * (max. pitch or roll term is the throttle value).
   * TODO: Why a growing function of yaw?
   */
  tmp_int = (int32_t)((int32_t)dynamicParams.DynamicStability * (int32_t)(throttleTerm + abs(yawTerm) / 2)) / 64;
  CHECK_MIN_MAX(pitchTerm, -tmp_int, tmp_int);
  CHECK_MIN_MAX(rollTerm, -tmp_int, tmp_int);

  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  // Universal Mixer
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  for(i = 0; i < MAX_MOTORS; i++) {
    int16_t tmp;
    if(Mixer.Motor[i][MIX_THROTTLE] > 0) { // If a motor has a zero throttle mix, it is not considered.
      tmp =  ((int32_t)throttleTerm * Mixer.Motor[i][MIX_THROTTLE]) / 64L;
      tmp += ((int32_t)pitchTerm    * Mixer.Motor[i][MIX_PITCH])    / 64L;
      tmp += ((int32_t)rollTerm     * Mixer.Motor[i][MIX_ROLL])     / 64L;
      tmp += ((int32_t)yawTerm      * Mixer.Motor[i][MIX_YAW])      / 64L;
      motorFilters[i] = motorFilter(tmp, motorFilters[i]);
      tmp = motorFilters[i] / STICK_GAIN;
      CHECK_MIN_MAX(tmp, staticParams.MinThrottle, staticParams.MaxThrottle);
      Motor[i].SetPoint = tmp;
    }
    else Motor[i].SetPoint = 0;
  }

  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  //  Debugwerte zuordnen
  // +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  if(!debugDataTimer--) {
    debugDataTimer = 24; // update debug outputs every 25*2ms = 50 ms (20Hz)
    DebugOut.Analog[0]  = (10 * pitchAngle) / GYRO_DEG_FACTOR_PITCHROLL; // in 0.1 deg
    DebugOut.Analog[1]  = (10 * rollAngle) / GYRO_DEG_FACTOR_PITCHROLL; // in 0.1 deg
    DebugOut.Analog[2]  = yawGyroHeading / GYRO_DEG_FACTOR_YAW;

    /*
    DebugOut.Analog[9]  = UBat;
    DebugOut.Analog[10] = RC_Quality;
    DebugOut.Analog[11] = yawGyroHeading / GYRO_DEG_FACTOR_YAW;
    */

    // 12..15 are the 4 first motors.

    DebugOut.Analog[16] = pitchAxisAcc;
    DebugOut.Analog[17] = rollAxisAcc;
    //    DebugOut.Analog[18] = ZAxisAcc;
    DebugOut.Analog[19] = throttleTerm;
    DebugOut.Analog[20] = pitchTerm;
    DebugOut.Analog[21] = rollTerm;
    DebugOut.Analog[22] = yawTerm;
    DebugOut.Analog[23] = PPartPitch;     //
    DebugOut.Analog[24] = IPartPitch /Ki; // meget meget lille.
    DebugOut.Analog[25] = PDPartPitch;    // omtrent lig ppart.

    DebugOut.Analog[26] = pitchAccNoisePeak;
    DebugOut.Analog[27] = rollAccNoisePeak;

    DebugOut.Analog[30] = pitchGyroNoisePeak;
    DebugOut.Analog[31] = rollGyroNoisePeak;
  }
}