Skip to main content
ANNU CHERIAN
ANNU CHERIAN
Associate II
September 9, 2017
Question

how to configure i2c in stm32f446 nucleo 144

  • September 9, 2017
  • 4 replies
  • 1432 views
Posted on September 09, 2017 at 07:18

The original post was too long to process during our migration. Please click on the attachment to read the original post.
    This topic has been closed for replies.

    4 replies

    ANNU CHERIAN
    ANNU CHERIANAuthor
    Associate II
    September 12, 2017
    Posted on September 12, 2017 at 13:50

    Why i2c data reception cannot be achieved from rtc in stm32f446. I can write data to rtc. I tried to receive data using hal driver but then also data reception doesn't occurs. 

                 

    HAL_I2C_Master_Receive(&hi2c2, 0xDF, data_read, 3, 1000);

    Tesla DeLorean
    Tesla DeLorean
    Guru
    September 12, 2017
    Posted on September 12, 2017 at 16:18

    Use 0xDE, and let the downstream code set the R/W bit

    I2C2->DR |= 0XDE;   // What the heck? Just write the register, don't OR it

    I2C2->DR |= 0x00; // Ok, this does what?

    Register level programming requires some grasp of what is going on

    Tips, Buy me a coffee, or three.. PayPal Venmo (See Profile) Up vote any posts that you find helpful, it shows what's working..
    ANNU CHERIAN
    ANNU CHERIANAuthor
    Associate II
    September 13, 2017
    Posted on September 13, 2017 at 15:11

    Thank you sir for your reply . I got the code for i2c write operation  when i enabled gpio output type as open drain and when OR operation removed .But i couldn't read

    data from rtc .Always data shows 0 .

    void i2c_start()

    {

        while(I2C2->SR2 & (1<<1));                                     // wait until I2C1 is not busy anymore

        I2C2->CR1 |= (1<<0);                                          // Peripheral enable

        I2C2->CR1 &= ~(1<<11);                                       // Disable POS

        I2C2->CR1 |= (I2C_CR1_START);                               // Send I2C1 START condition

        while(!((I2C2->SR1 & I2C_SR1_SB) && (I2C2->SR2 & 0x03)));   // wait for I2C1 EV5 (check start condition,bus busy,master mode)

        I2C2->DR = 0XDE;                                           // slave address

         while(!((I2C2->SR1 & 0X82) && (I2C2->SR2 & 0x07)));       // wait for I2C1 EV6 (check address sent,data bytes transmitted,bus busy,master mode)

    }

    void i2c_write()

    {

        I2C2->DR = 0x00;

        while(!((I2C2->SR1 & 0x84) && (I2C2->SR2 & 0x07)));         // check data register empty,data byte transfer succeeded

    }

    void i2c_restart()

    {

        I2C2->CR1 |= (I2C_CR1_START);                                      // Send I2C1 START condition

        while(!((I2C2->SR1 & I2C_SR1_SB) && (I2C2->SR2 & 0x03)));          // wait for I2C1 EV5 (check start condition,bus busy,master mode)

        I2C2->DR = 0XDF;                                                   // slave address

        I2C2->SR1 &= ~(1<<10);                                             // Acknowledge disable

         while(!((I2C2->SR1 & I2C_SR1_ADDR) && (I2C2->SR2 & 0x07)));        //wait for I2C1 EV6 (check address sent,data bytes transmitted,bus busy,master mode)

    }

    void i2c_stop()

    {

        I2C2->CR1 |= (I2C_CR1_STOP);

    }

    void i2c_read()

    {

        while((I2C1->SR1 & I2C_SR1_RXNE));

        data = I2C1->DR;

    }
    Terms & ConditionsAccessibility statement