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stm32f4 ,i2c and ds1621

Question asked by ali.med on May 13, 2015
Latest reply on May 13, 2015 by Clive One
I am using an stm32f4 dicovery with a ds1621.As indicated in the datasheets, i specified the adress as well as the device pins.
The problem is that when i run the program ,it seems to be stuck on the the first flag test instruction:while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_MODE_SELECT));
Can somebody tell me what is wrong?
#include "stm32f4xx.h"
#include "stm32f4xx_i2c.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "misc.h"
int main(void)
{int data=0;
GPIO_InitTypeDef GPIO_InitStructure;
    I2C_InitTypeDef I2C_InitStruct;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
  GPIO_Init(GPIOC, &GPIO_InitStructure);
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C3 , ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource8, GPIO_AF_I2C3);
  GPIO_PinAFConfig(GPIOC, GPIO_PinSource9, GPIO_AF_I2C3);
  I2C_InitStruct.I2C_ClockSpeed = 50000;
  I2C_InitStruct.I2C_Mode = I2C_Mode_I2C;
  I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2;
  I2C_InitStruct.I2C_OwnAddress1 = 0;//i tried to put 144 as well but nothing changed
  I2C_InitStruct.I2C_Ack = I2C_Ack_Enable;
  I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
  I2C_Init(I2C3, &I2C_InitStruct);
  I2C_Cmd(I2C3, ENABLE);
  while(1)
  { I2C_GenerateSTART(I2C3, ENABLE);
    while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_MODE_SELECT));
    I2C_Send7bitAddress( I2C3,0x90,I2C_Direction_Receiver);//I2C_Direction_Transmitter
    while( !I2C_CheckEvent(I2C3,I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
    I2C_SendData(I2C3, 0xAA);//read temperature
    while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_BYTE_TRANSMITTED))
    I2C_Send7bitAddress( I2C3,0x90,I2C_Direction_Transmitter);
    while( !I2C_CheckEvent(I2C3,I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
    data=I2C_ReceiveData(I2C3);
    while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_BYTE_RECEIVED))
    I2C_GenerateSTOP(I2C3, ENABLE);
    }
}

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