某マイコン付属プログラムより

main.c

int main(void)
{  
  uint8_t i = 0;
  /* SysTick end of count event each 10ms */
  RCC_GetClocksFreq(&RCC_Clocks);
  SysTick_Config(RCC_Clocks.HCLK_Frequency / 100);
  
  /* Initialize LEDs and User Button available on STM32F3-Discovery board */
  STM_EVAL_LEDInit(LED3);
  STM_EVAL_LEDInit(LED4);
  STM_EVAL_LEDInit(LED5);
  STM_EVAL_LEDInit(LED6);
  STM_EVAL_LEDInit(LED7);
  STM_EVAL_LEDInit(LED8);
  STM_EVAL_LEDInit(LED9);
  STM_EVAL_LEDInit(LED10);
  
  STM_EVAL_PBInit(BUTTON_USER, BUTTON_MODE_EXTI); 

  /* Configure the USB */
  Demo_USB();
  
  /* Reset UserButton_Pressed variable */
  UserButtonPressed = 0x00; 
   
  /* Infinite loop */
  while (1)
  {   
    /* LEDs Off */
    STM_EVAL_LEDOff(LED3);
    STM_EVAL_LEDOff(LED6);
    STM_EVAL_LEDOff(LED7);
    STM_EVAL_LEDOff(LED4);
    STM_EVAL_LEDOff(LED10);
    STM_EVAL_LEDOff(LED8);
    STM_EVAL_LEDOff(LED9);
    STM_EVAL_LEDOff(LED5);
    
    /* Waiting User Button is pressed */
    while (UserButtonPressed == 0x00)
    {
      /* Toggle LD3 */
      STM_EVAL_LEDToggle(LED3);
      /* Insert 50 ms delay */
      Delay(5);
      /* Toggle LD5 */
      STM_EVAL_LEDToggle(LED5);
      /* Insert 50 ms delay */
      Delay(5);
      /* Toggle LD7 */
      STM_EVAL_LEDToggle(LED7);
      /* Insert 50 ms delay */
      Delay(5);
      /* Toggle LD9 */
      STM_EVAL_LEDToggle(LED9);
      /* Insert 50 ms delay */
      Delay(5);
      /* Toggle LD10 */
      STM_EVAL_LEDToggle(LED10);
      /* Insert 50 ms delay */
      Delay(5);
      /* Toggle LD8 */
      STM_EVAL_LEDToggle(LED8);
      /* Insert 50 ms delay */
      Delay(5); 
      /* Toggle LD6 */
      STM_EVAL_LEDToggle(LED6);
      /* Insert 50 ms delay */
      Delay(5);
      /* Toggle LD4 */
      STM_EVAL_LEDToggle(LED4);
      /* Insert 50 ms delay */
      Delay(5);
    }
    
    DataReady = 0x00;
    
    /* All LEDs Off */
    STM_EVAL_LEDOff(LED3);
    STM_EVAL_LEDOff(LED6);
    STM_EVAL_LEDOff(LED7);
    STM_EVAL_LEDOff(LED4);
    STM_EVAL_LEDOff(LED10);
    STM_EVAL_LEDOff(LED8);
    STM_EVAL_LEDOff(LED9);
    STM_EVAL_LEDOff(LED5); 
    
    /* Demo Gyroscope */
    Demo_GyroConfig();

    /* Waiting User Button is pressed */
    while (UserButtonPressed == 0x01)
    {
      /* Wait for data ready */
      while(DataReady != 0x05)
      {}
      DataReady = 0x00;
      
      /* LEDs Off */
      STM_EVAL_LEDOff(LED3);
      STM_EVAL_LEDOff(LED6);
      STM_EVAL_LEDOff(LED7);
      STM_EVAL_LEDOff(LED4);
      STM_EVAL_LEDOff(LED10);
      STM_EVAL_LEDOff(LED8);
      STM_EVAL_LEDOff(LED9);
      STM_EVAL_LEDOff(LED5);
      
      /* Read Gyro Angular data */
      Demo_GyroReadAngRate(Buffer);
         
      /* Update autoreload and capture compare registers value*/
      Xval = ABS((int8_t)(Buffer[0]));
      Yval = ABS((int8_t)(Buffer[1])); 
      
      if ( Xval>Yval)
      {
        if ((int8_t)Buffer[0] > 5.0f)
        { 
          /* LD10 On */
          STM_EVAL_LEDOn(LED10);
        }
        if ((int8_t)Buffer[0] < -5.0f)
        { 
          /* LD3 On */
          STM_EVAL_LEDOn(LED3);
        }
      }
      else
      {
        if ((int8_t)Buffer[1] < -5.0f)
        {
          /* LD6 on */
          STM_EVAL_LEDOn(LED6);
        }
        if ((int8_t)Buffer[1] > 5.0f)
        {
          /* LD7 On */
          STM_EVAL_LEDOn(LED7);
        } 
      }
    }
        
    DataReady = 0x00;
    
    /* LEDs Off */
    STM_EVAL_LEDOff(LED4);
    STM_EVAL_LEDOff(LED3);
    STM_EVAL_LEDOff(LED6);
    STM_EVAL_LEDOff(LED7);
    STM_EVAL_LEDOff(LED10);
    STM_EVAL_LEDOff(LED8);
    STM_EVAL_LEDOff(LED9);
    STM_EVAL_LEDOff(LED5);
    
    /* Demo Compass */
    Demo_CompassConfig();
    
    /* Waiting User Button is pressed */
    while (UserButtonPressed == 0x02)
    {
      /* Wait for data ready */
      while(DataReady !=0x05)
      {}
      DataReady = 0x00;
      
      /* Read Compass data */
      Demo_CompassReadMag(MagBuffer);
      Demo_CompassReadAcc(AccBuffer);
      
      for(i=0;i<3;i++)
        AccBuffer[i] /= 100.0f;
      
      fNormAcc = sqrt((AccBuffer[0]*AccBuffer[0])+(AccBuffer[1]*AccBuffer[1])+(AccBuffer[2]*AccBuffer[2]));
      
      fSinRoll = -AccBuffer[1]/fNormAcc;
      fCosRoll = sqrt(1.0-(fSinRoll * fSinRoll));
      fSinPitch = AccBuffer[0]/fNormAcc;
      fCosPitch = sqrt(1.0-(fSinPitch * fSinPitch));
     if ( fSinRoll >0)
     {
       if (fCosRoll>0)
       {
         RollAng = acos(fCosRoll)*180/PI;
       }
       else
       {
         RollAng = acos(fCosRoll)*180/PI + 180;
       }
     }
     else
     {
       if (fCosRoll>0)
       {
         RollAng = acos(fCosRoll)*180/PI + 360;
       }
       else
       {
         RollAng = acos(fCosRoll)*180/PI + 180;
       }
     }
     
      if ( fSinPitch >0)
     {
       if (fCosPitch>0)
       {
            PitchAng = acos(fCosPitch)*180/PI;
       }
       else
       {
          PitchAng = acos(fCosPitch)*180/PI + 180;
       }
     }
     else
     {
       if (fCosPitch>0)
       {
            PitchAng = acos(fCosPitch)*180/PI + 360;
       }
       else
       {
          PitchAng = acos(fCosPitch)*180/PI + 180;
       }
     }

      if (RollAng >=360)
      {
        RollAng = RollAng - 360;
      }
      
      if (PitchAng >=360)
      {
        PitchAng = PitchAng - 360;
      }
      
      fTiltedX = MagBuffer[0]*fCosPitch+MagBuffer[2]*fSinPitch;
      fTiltedY = MagBuffer[0]*fSinRoll*fSinPitch+MagBuffer[1]*fCosRoll-MagBuffer[1]*fSinRoll*fCosPitch;
      
      HeadingValue = (float) ((atan2f((float)fTiltedY,(float)fTiltedX))*180)/PI;
 
      if (HeadingValue < 0)
      {
        HeadingValue = HeadingValue + 360;    
      }
      
      if ((RollAng <= 40.0f) && (PitchAng <= 40.0f))
      {
        if (((HeadingValue < 25.0f)&&(HeadingValue >= 0.0f))||((HeadingValue >=340.0f)&&(HeadingValue <= 360.0f)))
        {
          STM_EVAL_LEDOn(LED10);
          STM_EVAL_LEDOff(LED3);
          STM_EVAL_LEDOff(LED6);
          STM_EVAL_LEDOff(LED7);
          STM_EVAL_LEDOff(LED4);
          STM_EVAL_LEDOff(LED8);
          STM_EVAL_LEDOff(LED9);
          STM_EVAL_LEDOff(LED5);
        }
        else  if ((HeadingValue <70.0f)&&(HeadingValue >= 25.0f))
        {
          STM_EVAL_LEDOn(LED9);
          STM_EVAL_LEDOff(LED6);
          STM_EVAL_LEDOff(LED10);
          STM_EVAL_LEDOff(LED3);
          STM_EVAL_LEDOff(LED8);
          STM_EVAL_LEDOff(LED5);
          STM_EVAL_LEDOff(LED4);
          STM_EVAL_LEDOff(LED7);
        } 
        else  if ((HeadingValue < 115.0f)&&(HeadingValue >= 70.0f))
        {
          STM_EVAL_LEDOn(LED7);
          STM_EVAL_LEDOff(LED3);
          STM_EVAL_LEDOff(LED4);
          STM_EVAL_LEDOff(LED9);
          STM_EVAL_LEDOff(LED10);
          STM_EVAL_LEDOff(LED8);
          STM_EVAL_LEDOff(LED6);
          STM_EVAL_LEDOff(LED5);
        }
        else  if ((HeadingValue <160.0f)&&(HeadingValue >= 115.0f))
        {
          STM_EVAL_LEDOn(LED5);
          STM_EVAL_LEDOff(LED6);
          STM_EVAL_LEDOff(LED10);
          STM_EVAL_LEDOff(LED8);
          STM_EVAL_LEDOff(LED9);
          STM_EVAL_LEDOff(LED7);
          STM_EVAL_LEDOff(LED4);
          STM_EVAL_LEDOff(LED3);
        } 
        else  if ((HeadingValue <205.0f)&&(HeadingValue >= 160.0f))
        {
          STM_EVAL_LEDOn(LED3);
          STM_EVAL_LEDOff(LED6);
          STM_EVAL_LEDOff(LED4);
          STM_EVAL_LEDOff(LED8);
          STM_EVAL_LEDOff(LED9);
          STM_EVAL_LEDOff(LED5);
          STM_EVAL_LEDOff(LED10);
          STM_EVAL_LEDOff(LED7);
        } 
        else  if ((HeadingValue <250.0f)&&(HeadingValue >= 205.0f))
        {
          STM_EVAL_LEDOn(LED4);
          STM_EVAL_LEDOff(LED6);
          STM_EVAL_LEDOff(LED10);
          STM_EVAL_LEDOff(LED8);
          STM_EVAL_LEDOff(LED9);
          STM_EVAL_LEDOff(LED5);
          STM_EVAL_LEDOff(LED3);
          STM_EVAL_LEDOff(LED7);
        } 
        else  if ((HeadingValue < 295.0f)&&(HeadingValue >= 250.0f))
        {
          STM_EVAL_LEDOn(LED6);
          STM_EVAL_LEDOff(LED9);
          STM_EVAL_LEDOff(LED10);
          STM_EVAL_LEDOff(LED8);
          STM_EVAL_LEDOff(LED3);
          STM_EVAL_LEDOff(LED5);
          STM_EVAL_LEDOff(LED4);
          STM_EVAL_LEDOff(LED7);
        }        
        else  if ((HeadingValue < 340.0f)&&(HeadingValue >= 295.0f))
        {
          STM_EVAL_LEDOn(LED8);
          STM_EVAL_LEDOff(LED6);
          STM_EVAL_LEDOff(LED10);
          STM_EVAL_LEDOff(LED7);
          STM_EVAL_LEDOff(LED9);
          STM_EVAL_LEDOff(LED3);
          STM_EVAL_LEDOff(LED4);
          STM_EVAL_LEDOff(LED5);
        }
      }
      else
      {
        /* Toggle All LEDs */
        STM_EVAL_LEDToggle(LED7);
        STM_EVAL_LEDToggle(LED6);
        STM_EVAL_LEDToggle(LED10);
        STM_EVAL_LEDToggle(LED8);
        STM_EVAL_LEDToggle(LED9);
        STM_EVAL_LEDToggle(LED3);
        STM_EVAL_LEDToggle(LED4);
        STM_EVAL_LEDToggle(LED5);
        /* Delay 50ms */
        Delay(5);
      }
    }
  }
}

元ネタ: STSW-STM32118 - STMicroelectronics http://www.st.com/web/en/catalog/tools/PF258154