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();
}