Subversion Repositories FlightCtrl

#include <inttypes.h>

#include <avr/io.h>

#include <avr/interrupt.h>

#include "eeprom.h"

#include "analog.h"

#include "main.h"

#include "fc.h"

#include "mm3.h"

volatile uint16_t CountMilliseconds = 0;

volatile uint8_t UpdateMotor = 0;

volatile uint16_t cntKompass = 0;

volatile uint16_t BeepTime = 0;

volatile uint16_t BeepModulation = 0xFFFF;

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

/*              Initialize Timer 0                   */

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

// timer 0 is used for the PWM generation to control the offset voltage at the air pressure sensor

// Its overflow interrupt routine is used to generate the beep signal and the flight control motor update rate

void TIMER0_Init(void)

{

        uint8_t sreg = SREG;

        // disable all interrupts before reconfiguration

        cli();

        // configure speaker port as output

        if(BoardRelease == 10)

        {       // Speaker at PD2

                DDRD |= (1<<DDD2);

                PORTD &= ~(1<<PORTD2);

        }

        else

        {       // Speaker at PC7

                DDRC |= (1<<DDC7);

                PORTC &= ~(1<<PORTC7);

        }

        // set PB3 and PB4 as output for the PWM used as aoffset for the pressure sensor

        DDRB |= (1<<DDB4)|(1<<DDB3);

        PORTB &= ~((1<<PORTB4)|(1<<PORTB3));

        if(BoardRelease == 10)

        {

                DDRD |= (1<<DDD2);

                PORTD &= ~(1<<PORTD2);

        }

        else

        {

                DDRC |= (1<<DDC7);

                PORTC &= ~(1<<PORTC7);

        }

        // Timer/Counter 0 Control Register A

        // Waveform Generation Mode is Fast PWM (Bits WGM02 = 0, WGM01 = 1, WGM00 = 1)

    // Clear OC0A on Compare Match, set OC0A at BOTTOM, noninverting PWM (Bits COM0A1 = 1, COM0A0 = 0)

    // Clear OC0B on Compare Match, set OC0B at BOTTOM, (Bits COM0B1 = 1, COM0B0 = 0)

    TCCR0A &= ~((1<<COM0A0)|(1<<COM0B0));

    TCCR0A |= (1<<COM0A1)|(1<<COM0B1)|(1<<WGM01)|(1<<WGM00);

        // Timer/Counter 0 Control Register B

        // set clock devider for timer 0 to SYSKLOCK/8 = 20MHz / 8 = 2.5MHz

        // i.e. the timer increments from 0x00 to 0xFF with an update rate of 2.5 MHz

        // hence the timer overflow interrupt frequency is 2.5 MHz / 256 = 9.765 kHz

        // divider 8 (Bits CS02 = 0, CS01 = 1, CS00 = 0)

        TCCR0B &= ~((1<<FOC0A)|(1<<FOC0B)|(1<<WGM02));

    TCCR0B = (TCCR0B & 0xF8)|(0<<CS02)|(1<<CS01)|(0<<CS00);

        // initialize the Output Compare Register A & B used for PWM generation on port PB3 & PB4

    OCR0A =  0;  // for PB3

    OCR0B = 120; // for PB4

        // init Timer/Counter 0 Register

    TCNT0 = 0;

        // Timer/Counter 0 Interrupt Mask Register

        // enable timer overflow interrupt only

        TIMSK0 &= ~((1<<OCIE0B)|(1<<OCIE0A));

        TIMSK0 |= (1<<TOIE0);

        SREG = sreg;

}

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

/*          Interrupt Routine of Timer 0             */

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

ISR(TIMER0_OVF_vect)    // 9.765 kHz

{

    static uint8_t cnt_1ms = 1,cnt = 0;

    uint8_t Beeper_On = 0;

        if(!cnt--) // every 10th run (9.765kHz/10 = 976Hz)

        {

         cnt = 9;

         cnt_1ms++;

         cnt_1ms %= 2;

         if(!cnt_1ms) UpdateMotor = 1; // every 2nd run (976Hz/2 = 488 Hz)

         CountMilliseconds++; // increment millisecond counter

        }

        // beeper on if duration is not over

        if(BeepTime > 1)

        {

           BeepTime--; // decrement BeepTime

           if(BeepTime & BeepModulation) Beeper_On = 1;

           else Beeper_On = 0;

        }

        else // beeper off if duration is over

        {

           Beeper_On = 0;

           BeepModulation = 0xFFFF;

        }

        // if beeper is on

        if(Beeper_On)

        {

                // set speaker port to high

                if(BoardRelease == 10) PORTD |= (1<<PORTD2); // Speaker at PD2

                else                   PORTC |= (1<<PORTC7); // Speaker at PC7

        }

        else // beeper is off

        {

                // set speaker port to low

                if(BoardRelease == 10) PORTD &= ~(1<<PORTD2);// Speaker at PD2

                else                   PORTC &= ~(1<<PORTC7);// Speaker at PC7

        }

        // update compass value if this option is enabled in the settings

        if(ParamSet.GlobalConfig & CFG_COMPASS_ACTIVE)

        {

                MM3_timer0(); // read out mm3 board

        }

}

// -----------------------------------------------------------------------

uint16_t SetDelay (uint16_t t)

{

  return(CountMilliseconds + t + 1);

}

// -----------------------------------------------------------------------

int8_t CheckDelay(uint16_t t)

{

  return(((t - CountMilliseconds) & 0x8000) >> 9); // check sign bit

}

// -----------------------------------------------------------------------

void Delay_ms(uint16_t w)

{

 unsigned int t_stop;

 t_stop = SetDelay(w);

 while (!CheckDelay(t_stop));

}

// -----------------------------------------------------------------------

void Delay_ms_Mess(uint16_t w)

{

 uint16_t t_stop;

 t_stop = SetDelay(w);

 while (!CheckDelay(t_stop)) ADC_Enable();

}