STM32F0 I2C code doesn't work

Nickname925_O · ‎2013-11-22

Posted on November 22, 2013 at 17:10

Hi,

here my code for I2C setup on STM32F051R8 (STM32 discovery board practically)

void set_I2C(void){

GPIO_InitTypeDef GPIO_InitStructure;

I2C_InitTypeDef I2C_InitStructure;

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);

/* Configure the I2C clock source. The clock is derived from the HSI */

RCC_I2CCLKConfig(RCC_I2C1CLK_SYSCLK);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_1);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_1);

//Configure pins: SCL and SDA ------------------

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;

GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;

GPIO_Init(GPIOB, &GPIO_InitStructure);

I2C_InitStructure.I2C_AnalogFilter = I2C_AnalogFilter_Enable;

I2C_InitStructure.I2C_DigitalFilter = 0x00;

I2C_InitStructure.I2C_OwnAddress1 = 0x00; // MPU6050 7-bit adress = 0x68, 8-bit adress = 0xD0;

I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;

I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;

//I2C_InitStructure.I2C_Timing = 0xA0120227;

I2C_InitStructure.I2C_Timing = 0x20310A0D;

I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;

I2C_Init(I2C1, &I2C_InitStructure);

I2C_Cmd(I2C1, ENABLE);

}

but when in the main I try to send one data:

I2C_SendData(I2C1, 0xAA);

I don't see any signal on the Pb6 PB7.

Please, can you tell me what's wrong?

Thanks a lot in advance.

#stm32 #i2c #stm32f0

Nickname925_O · ‎2013-11-28

Posted on November 29, 2013 at 08:11

Hi Clive,

today I tried this instruction:

I2C_GenerateSTART(I2C1,

ENABLE

);

and I see with the scope che clock and one data... so it seems the I2C is correctly set up... but how can I send my desiderd data on the bus?

I hope you can help me... I have no othe ideas.. :-(

christhiele · ‎2014-11-04

Posted on November 04, 2014 at 17:48

Hi there,

Did you solve this problem? I've been having the same issue lately in where I can't even get garbage data outputting on the I2C bus.