Subversion Repositories FlightCtrl

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Copyright (c) 04.2007 Holger Buss

// + only for non-profit use

// + www.MikroKopter.com

// + see the File "License.txt" for further Informations

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

#include <stdlib.h>

#include <avr/io.h>

#include <avr/interrupt.h>

#include "analog.h"

#include "main.h"

#include "timer0.h"

#include "fc.h"

#include "printf_P.h"

#include "eeprom.h"

volatile int16_t Current_AccZ = 0;

volatile int16_t UBat = 100;

volatile int16_t AdValueGyrPitch = 0, AdValueGyrRoll = 0,  AdValueGyrYaw = 0;

volatile int16_t AdValueAccRoll = 0,  AdValueAccPitch = 0, AdValueAccTop = 0;

volatile int32_t AirPressure = 32000;

volatile int16_t StartAirPressure;

volatile uint16_t ReadingAirPressure = 1023;

uint8_t PressureSensorOffset;

volatile int16_t HeightD = 0;

volatile uint16_t MeasurementCounter = 0;

/*****************************************************/

/*     Initialize Analog Digital Converter           */

/*****************************************************/

void ADC_Init(void)

{

        uint8_t sreg = SREG;

        // disable all interrupts before reconfiguration

        cli();

        //ADC0 ... ADC7 is connected to PortA pin 0 ... 7

        DDRA = 0x00;

        PORTA = 0x00;

        // Digital Input Disable Register 0

        // Disable digital input buffer for analog adc_channel pins

        DIDR0 = 0xFF;

        // external reference, adjust data to the right

    ADMUX &= ~((1 << REFS1)|(1 << REFS0)|(1 << ADLAR));

    // set muxer to ADC adc_channel 0 (0 to 7 is a valid choice)

    ADMUX = (ADMUX & 0xE0) | 0x00;

    //Set ADC Control and Status Register A

    //Auto Trigger Enable, Prescaler Select Bits to Division Factor 128, i.e. ADC clock = SYSCKL/128 = 156.25 kHz

    ADCSRA = (1<<ADATE)|(1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0);

        //Set ADC Control and Status Register B

        //Trigger Source to Free Running Mode

        ADCSRB &= ~((1 << ADTS2)|(1 << ADTS1)|(1 << ADTS0));

        // Enable AD conversion

        ADC_Enable();

    // restore global interrupt flags

    SREG = sreg;

}

void SearchAirPressureOffset(void)

{

        uint8_t off;

        off = GetParamByte(PID_PRESSURE_OFFSET);

        if(off > 20) off -= 10;

        OCR0A = off;

        Delay_ms_Mess(100);

        if(ReadingAirPressure < 850) off = 0;

        for(; off < 250;off++)

        {

                OCR0A = off;

                Delay_ms_Mess(50);

                printf(".");

                if(ReadingAirPressure < 900) break;

        }

        SetParamByte(PID_PRESSURE_OFFSET, off);

        PressureSensorOffset = off;

        Delay_ms_Mess(300);

}

/*****************************************************/

/*     Interrupt Service Routine for ADC             */

/*****************************************************/

// runs at 156.25 kHz or 6.4 µs

// if after (70.4µs) all 11 states are processed the interrupt is disabled

// and the update of further ads is stopped

// The routine changes the ADC input muxer running

// thru the state machine by the following order.

// state 0: ch0 (yaw gyro)

// state 1: ch1 (roll gyro)

// state 2: ch2 (pitch gyro)

// state 3: ch4 (battery voltage -> UBat)

// state 4: ch6 (acc y -> Current_AccY)

// state 5: ch7 (acc x -> Current_AccX)

// state 6: ch0 (yaw gyro average with first reading   -> AdValueGyrYaw)

// state 7: ch1 (roll gyro average with first reading  -> AdValueGyrRoll)

// state 8: ch2 (pitch gyro average with first reading -> AdValueGyrPitch)

// state 9: ch5 (acc z add also 4th part of acc x and acc y to reading)

// state10: ch3 (air pressure averaging over 5 single readings -> tmpAirPressure)

ISR(ADC_vect)

{

    static uint8_t adc_channel = 0, state = 0;

    static uint16_t yaw1, roll1, pitch1;

    static uint8_t average_pressure = 0;

    static int16_t tmpAirPressure = 0;

    // disable further AD conversion

    ADC_Disable();

    // state machine

    switch(state++)

        {

        case 0:

            yaw1 = ADC; // get Gyro Yaw Voltage 1st sample

            adc_channel = 1; // set next channel to ADC1 = ROLL GYRO

            MeasurementCounter++; // increment total measurement counter

            break;

        case 1:

            roll1 = ADC; // get Gyro Roll Voltage 1st sample

            adc_channel = 2; // set next channel to ADC2 = PITCH GYRO

            break;

        case 2:

            pitch1 = ADC; // get Gyro Pitch Voltage 1st sample

            adc_channel = 4; // set next channel to ADC4 = UBAT

            break;

        case 3:

                // get actual UBat (Volts*10) is ADC*30V/1024*10 = ADC/3

            UBat = (3 * UBat + ADC / 3) / 4; // low pass filter updates UBat only to 1 quater with actual ADC value

            adc_channel = 6; // set next channel to ADC6 = ACC_Y

            break;

        case 4:

            AdValueAccRoll = NeutralAccY - ADC; // get acceleration in Y direction

            adc_channel = 7; // set next channel to ADC7 = ACC_X

            break;

        case 5:

            AdValueAccPitch = ADC - NeutralAccX; // get acceleration in X direction

                    adc_channel = 0; // set next channel to ADC7 = YAW GYRO

            break;

        case 6:

                // average over two samples to create current AdValueGyrYaw

            if(BoardRelease == 10)  AdValueGyrYaw = (ADC + yaw1) / 2;

                        else                                    AdValueGyrYaw = ADC + yaw1; // gain is 2 times lower on FC 1.1

            adc_channel = 1; // set next channel to ADC7 = ROLL GYRO

            break;

        case 7:

                // average over two samples to create current ADValueGyrRoll

            if(BoardRelease == 10)  AdValueGyrRoll = (ADC + roll1) / 2;

                        else                                    AdValueGyrRoll = ADC + roll1; // gain is 2 times lower on FC 1.1

            adc_channel = 2; // set next channel to ADC2 = PITCH GYRO

            break;

        case 8:

                // average over two samples to create current ADValuePitch

            if(BoardRelease == 10)  AdValueGyrPitch = (ADC + pitch1) / 2;

                        else                                    AdValueGyrPitch = ADC + pitch1; // gain is 2 times lower on FC 1.1

            adc_channel = 5; // set next channel to ADC5 = ACC_Z

            break;

       case 9:

                // get z acceleration

            AdValueAccTop =  (int16_t) ADC - NeutralAccZ; // get plain acceleration in Z direction

            AdValueAccTop += abs(AdValueAccPitch) / 4 + abs(AdValueAccRoll) / 4;

            if(AdValueAccTop > 1)

             {

                if(NeutralAccZ < 800) NeutralAccZ+= 0.02;

             }

             else if(AdValueAccTop < -1)

             {

                if(NeutralAccZ > 600) NeutralAccZ-= 0.02;

             }

            Current_AccZ = ADC;

            Reading_Integral_Top += AdValueAccTop;      // Integrieren

            Reading_Integral_Top -= Reading_Integral_Top / 1024; // dämfen

                adc_channel = 3; // set next channel to ADC3 = air pressure

            break;

        case 10:

            tmpAirPressure += ADC; // sum vadc values

            if(++average_pressure >= 5) // if 5 values are summerized for averaging

            {

                ReadingAirPressure = ADC; // update measured air pressure

                                HeightD = (int16_t)(StartAirPressure - tmpAirPressure - ReadingHeight);  // D-Anteil = neuerWert - AlterWert

                AirPressure = (tmpAirPressure + 3 * AirPressure) / 4; // averaging using history

                ReadingHeight = StartAirPressure - AirPressure;

                average_pressure = 0; // reset air pressure measurement counter

                tmpAirPressure = 0;

            }

            adc_channel = 0; // set next channel to ADC0 = GIER GYRO

            state = 0; // reset state machine

            break;

        default:

            adc_channel = 0;

            state = 0;

            break;

        }

    // set adc muxer to next adc_channel

    ADMUX = (ADMUX & 0xE0) | adc_channel;

    // after full cycle stop further interrupts

    if(state != 0) ADC_Enable();

}