I2C mit STM32 STK3700

int main(void)

{

  /* Chip errata */

  CHIP_Init();

  /* Enable clocks required */

  CMU_ClockEnable(cmuClock_HFPER, true);

  /* Enabling clock to the I2C */

  CMU_ClockEnable(cmuClock_I2C0, true);  

  CMU_ClockEnable(cmuClock_GPIO, true);

  CMU_ClockEnable(cmuClock_CORELE, true); //??

  /* Starting LFXO and waiting until it is stable */

  CMU_OscillatorEnable(cmuOsc_LFXO, true, true);

  /* Routing the LFXO clock to the RTC */

  CMU_ClockSelectSet(cmuClock_LFA,cmuSelect_LFXO);

  CMU_ClockEnable(cmuClock_RTC, true);

  /* Setup SysTick Timer for 1 msec interrupts  */

  if (SysTick_Config(CMU_ClockFreqGet(cmuClock_CORE) / 1000)) while (1) ;

  /* Enable LCD without voltage boost */

  SegmentLCD_Init(false);

  setupI2C();

  Read_I2C_Data();

...

}

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

 * @brief  Setup I2C

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

void setupI2C(void)

{

  // Using default settings

  I2C_Init_TypeDef i2cInit = I2C_INIT_DEFAULT;

  /* Using PD6 (SDA) and PD7 (SCL) */

  GPIO_PinModeSet(gpioPortD, 7, gpioModeWiredAndPullUpFilter, 1);

  GPIO_PinModeSet(gpioPortD, 6, gpioModeWiredAndPullUpFilter, 1);

  /* Enable pins at location 1 */

  I2C0->ROUTE = I2C_ROUTE_SDAPEN |

                I2C_ROUTE_SCLPEN |

                (1 << _I2C_ROUTE_LOCATION_SHIFT);

  /* Initializing the I2C */

  I2C_Init(I2C0, &i2cInit);

  I2C_Enable(I2C0, 1);

}

void Read_I2C_Data(){

  I2C_TransferReturn_TypeDef I2C_Status;

  uint8_t write_value[1];

  write_value[1]=128;

  I2C_TransferSeq_TypeDef seq;

  seq.addr = 0x58;

  seq.flags = I2C_FLAG_WRITE_WRITE;

  seq.buf[0].len = 1;

  seq.buf[0].data = 0;

  seq.buf[1].len = 1;

  seq.buf[1].data = write_value; 

  I2C_Status = I2C_TransferInit(I2C0, &seq);

  while(I2C_Status == i2cTransferInProgress){

    I2C_Status=I2C_Transfer(I2C0);

  }

  int i=0;

  i++;

}