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stm32 accelerometer

Question asked by yurtseven.eray on Apr 30, 2014
Latest reply on May 1, 2014 by sung.chen_chung
hi, I have a problem. I2C busy flag always set.
 
I am using I2C1 peripherel. this peripherel conected EEPROM, IO expander and Lis302dl

I think, problem is attaching EEPROM  or  IO expander.
how can I disconnect EEPROM and IO expander using software. 

If this is not the problem, what is problem ?

my configuration codes:

     GPIO_InitTypeDef GPIO_InitStructure;
     I2C_InitTypeDef I2C_InitStructure;     
     
     RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
     RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);     
     
     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;                       //GPIO_Mode_AF_PP;
     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;     
     GPIO_Init(GPIOB,&GPIO_InitStructure);
     
     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
     GPIO_Init(GPIOB,&GPIO_InitStructure);


     I2C_Cmd(I2C1, ENABLE);
     I2C_InitStructure.I2C_Mode = I2C_Mode_I2C; 
     I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2; 
     I2C_InitStructure.I2C_OwnAddress1 = 0x00; 
     I2C_InitStructure.I2C_Ack = I2C_Ack_Enable; 
     I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; 
     I2C_InitStructure.I2C_ClockSpeed = 100000; 
     I2C_Init(I2C1, &I2C_InitStructure);

codes for reading process:

     unsigned char uc;
     I2C_GenerateSTART(I2C1, ENABLE); 
  while (!(I2C_sr() & 0x0001));  // start condition generate edilene kkadar bekliyoz. 
     I2C_Send7bitAddress(I2C1, address, I2C_Direction_Transmitter);
  while (!(I2C_sr() & 0x0002));     //Addr sent olana kadan bekle 
     I2C_SendData(I2C1,cmd); 
  while (!(I2C_sr() & 0x00000004));     /* Wait until BTF bit set             */ 
  I2C_GenerateSTART(I2C1, ENABLE); 
  while (!(I2C_sr() & 0x0001));  // start condition generate edilene kkadar bekliyoz. 
     I2C_Send7bitAddress(I2C1, address,I2C_Direction_Receiver); 
  while (!(I2C_sr() & 0x0002));     //Addr sent olana kadan bekle 
     uc = I2C_ReceiveData(I2C1); 
  while (!(I2C_sr() & 0x00000040));     /* Wait until RxNE bit set            */
     I2C_GenerateSTOP(I2C1, ENABLE); 
     while (I2C_sr() & 0x00020000);        /* Wait until BUSY bit reset          */
     return( uc );

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