WebSVN - FlightCtrl - Diff - Rev 1805 and 1821 - /branches/dongfang_FC

  * 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;
+        uint8_t sreg = SREG;
-  // disable all interrupts before reconfiguration
+        // disable all interrupts before reconfiguration
-  cli();
+        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 offset for the pressure sensor
-  DDRB |= (1<<DDB4)|(1<<DDB3);
-  PORTB &= ~((1<<PORTB4)|(1<<PORTB3));
-  // 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 divider 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
+        // 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 offset for the pressure sensor
+        DDRB |= (1 << DDB4) | (1 << DDB3);
+        PORTB &= ~((1 << PORTB4) | (1 << PORTB3));
+        // 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 divider 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 << OCIE0B) | (1 << OCIE0A));
-  TIMSK0 |= (1<<TOIE0);
+        TIMSK0 |= (1 << TOIE0);
-  SREG = sreg;
+        SREG = sreg;
+}
+/*****************************************************/
-/*****************************************************/
+/*          Interrupt Routine of Timer 0             */
-/*          Interrupt Routine of Timer 0             */
+/*****************************************************/
-/*****************************************************/
+ISR(TIMER0_OVF_vect)
-ISR(TIMER0_OVF_vect) {    // 9765.625 Hz
+{ // 9765.625 Hz
-  static uint8_t cnt_1ms = 1,cnt = 0;
+        static uint8_t cnt_1ms = 1, cnt = 0;
-  uint8_t Beeper_On = 0;
+        uint8_t Beeper_On = 0;
 #ifdef USE_NAVICTRL
-  if(SendSPI) SendSPI--; // if SendSPI is 0, the transmit of a byte via SPI bus to and from The Navicontrol is done
+        if(SendSPI) SendSPI--; // if SendSPI is 0, the transmit of a byte via SPI bus to and from The Navicontrol is done
 #endif
-  if(!cnt--) { // every 10th run (9.765kHz/10 = 976Hz)
+        if (!cnt--) { // every 10th run (9.765kHz/10 = 976Hz)
-    cnt = 9;
+                cnt = 9;
-    cnt_1ms^=1;
+                cnt_1ms ^= 1;
-    if(!cnt_1ms) {
+                if (!cnt_1ms) {
-        runFlightControl = 1; // every 2nd run (976.5625 Hz/2 = 488.28125 Hz)
+                        runFlightControl = 1; // every 2nd run (976.5625 Hz/2 = 488.28125 Hz)
-    }
+                }
-    CountMilliseconds++; // increment millisecond counter
+                CountMilliseconds++; // increment millisecond counter
-  }
+        }
-  // beeper on if duration is not over
+        // beeper on if duration is not over
-  if(BeepTime) {
+        if (BeepTime) {
+                BeepTime--; // decrement BeepTime
-    BeepTime--; // decrement BeepTime
+                if (BeepTime & BeepModulation)
-    if(BeepTime & BeepModulation) Beeper_On = 1;
+                        Beeper_On = 1;
-    else Beeper_On = 0;
+                else
-  }
+                        Beeper_On = 0;
-  else { // beeper off if duration is over
+        } else { // beeper off if duration is over
-    Beeper_On = 0;
+                Beeper_On = 0;
-    BeepModulation = 0xFFFF;
+                BeepModulation = 0xFFFF;
-  }
+        }
+        // if beeper is on
+        if (Beeper_On) {
-  // if beeper is on
+                // set speaker port to high.
-  if(Beeper_On) {
+                if (BoardRelease == 10)
-    // set speaker port to high.
+                        PORTD |= (1 << PORTD2); // Speaker at PD2
+                else
-    if(BoardRelease == 10) PORTD |= (1<<PORTD2); // Speaker at PD2
+                        PORTC |= (1 << PORTC7); // Speaker at PC7
+        } else { // beeper is off
-    else PORTC |= (1<<PORTC7); // Speaker at PC7
+                // set speaker port to low
-  } else { // beeper is off
+                if (BoardRelease == 10)
-    // set speaker port to low
+                        PORTD &= ~(1 << PORTD2);// Speaker at PD2
-    if(BoardRelease == 10) PORTD &= ~(1<<PORTD2);// Speaker at PD2
+                else
-    else PORTC &= ~(1<<PORTC7);// Speaker at PC7
+                        PORTC &= ~(1 << PORTC7);// Speaker at PC7
-  }
+        }
 #ifndef USE_NAVICTRL
-  // update compass value if this option is enabled in the settings
+        // update compass value if this option is enabled in the settings
-  if(staticParams.GlobalConfig & (CFG_COMPASS_ACTIVE|CFG_GPS_ACTIVE)) {
+        if (staticParams.GlobalConfig & (CFG_COMPASS_ACTIVE | CFG_GPS_ACTIVE)) {
 #ifdef USE_MK3MAG
-    MK3MAG_Update(); // read out mk3mag pwm
+                MK3MAG_Update(); // read out mk3mag pwm
 #endif
-  }
+        }
 #endif
+}
 // -----------------------------------------------------------------------
-uint16_t SetDelay (uint16_t t) {
+uint16_t SetDelay(uint16_t t) {
-  return(CountMilliseconds + t - 1);
+        return (CountMilliseconds + t - 1);
+}
 // -----------------------------------------------------------------------
 int8_t CheckDelay(uint16_t t) {
+        return (((t - CountMilliseconds) & 0x8000) >> 8); // check sign bit
   return(((t - CountMilliseconds) & 0x8000) >> 8); // check sign bit
 // -----------------------------------------------------------------------
-// -----------------------------------------------------------------------
+void Delay_ms(uint16_t w) {
-void Delay_ms(uint16_t w) {
+        uint16_t t_stop = SetDelay(w);
-  uint16_t t_stop = SetDelay(w);
+        while (!CheckDelay(t_stop))
-  while (!CheckDelay(t_stop));
+                ;
 }
 // -----------------------------------------------------------------------
 void Delay_ms_Mess(uint16_t w) {
-  uint16_t t_stop;
+        uint16_t t_stop;

Subversion Repositories FlightCtrl

(root)/branches/dongfang_FC_rewrite/timer0.c - Rev 1805 → 1821