Posted on November 29, 2016 at 10:56Hello everyone,
for my current project I am trying to communicate with my STM32F407 Discovery board via I2C. I want to poll different data from it using an Arduino board, similar to a sensor I have. The sensor polling already works and is as follows: I send send the address with a write bit, then a register I want the value from, then I send the slave address once more, only this time with a read bit. I then expect a float.
So far I have managed to detect my STM using a scanner I implemented. I have trouble moving on from there though mainly because I do not understand the driver description of the HAL library I suppose.
My code:
//I2C Initialization
I2C_HandleTypeDef hi2c1;
void InitializeI2C1()
{
__I2C1_CLK_ENABLE();
hi2c1.Instance = I2C1;
hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
hi2c1.Init.ClockSpeed = 100000;
hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLED;
hi2c1.Init.DutyCycle = I2C_DUTYCYCLE_2;
hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLED;
hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLED;
hi2c1.Init.OwnAddress1 = 0x25<<1;
if (HAL_I2C_Init(&hi2c1) != HAL_OK)
{
Error_Handler();
}
HAL_NVIC_SetPriority(I2C1_EV_IRQn,0,1);
HAL_NVIC_EnableIRQ(I2C1_EV_IRQn);
__GPIOB_CLK_ENABLE();
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Pin = GPIO_PIN_6|GPIO_PIN_7;
GPIO_InitStructure.Mode = GPIO_MODE_AF_OD; //
GPIO_InitStructure.Speed = GPIO_SPEED_HIGH;
GPIO_InitStructure.Pull = GPIO_PULLUP;
GPIO_InitStructure.Alternate = GPIO_AF4_I2C1;
HAL_GPIO_Init(GPIOB, &GPIO_InitStructure);
HAL_I2C_EnableListen_IT(&hi2c1);
}
extern ''C'' void I2C1_EV_IRQHandler()
{
HAL_I2C_EV_IRQHandler(&hi2c1);
}
// My code for the (already functioning) detect:
void HAL_I2C_AddrCallback(I2C_HandleTypeDef * hi2c, uint8_t TransferDirection, uint16_t AddrMatchCode)
{
}
void HAL_I2C_ListenCpltCallback(I2C_HandleTypeDef * hi2c)
{
HAL_I2C_EnableListen_IT(&hi2c1);
}
void main()
{
InitializeI2C1();
while(1)
{
}
}
For the next step I am just sending the 1 byte register address. So, on the STM board the question is: what do I do? I assume I still have to have the HAL_I2C_EnableListen_IT, otherwise no transmission will take place, correct? Where in the code should I implement the HAL_I2C_Slave_Receive_IT because if I do it in the HAL_I2C_AddrCallback, the I2C line gets help up and nothing works anymore. The same applies if I put it in my main...
Thank you for your time.
