STM32F103 holding I2C

[Ryan-SmartIR]

I am trying to use the F103 as a I2C master but it is holding the I2C pins low, there is nothing else on the bus 5k1 pullups, when I hold the device in reset the lines are 5V. 

Because the lines are low, SB is never being set, so the first while statement of the transmit function is blocking. 

Any suggestions as to what could be causing this? I have no ideas left. 

/* USER CODE BEGIN */ 

//----------------------------------------------------------------------

//                                      I2C init

//----------------------------------------------------------------------

void ll_i2c1_init(void){

RCC->APB1RSTR |= RCC_APB1RSTR_I2C1RST;

RCC->APB1RSTR &= ~RCC_APB1RSTR_I2C1RST;

I2C1->CR1 &= ~I2C_CR1_PE;

I2C1->CR1 |= I2C_CR1_SWRST;

I2C1->CR1 &= ~I2C_CR1_SWRST;

ll_clocks_enable_i2c1(); 

ll_gpio_remap_i2c1();

I2C1->CR2 |= 16;

I2C1->CCR |= 0x50;

I2C1->TRISE = 0x10;

I2C1->OAR1 |= (0x14 << 1); 

I2C1->CR1 |= I2C_CR1_PE; //Peripheral Enable

}

//----------------------------------------------------------------------

//                                      Transmit

//----------------------------------------------------------------------

void ll_i2c1_transmit(uint8_t address, uint8_t message){

uint16_t status_register_1_read = 0;

address = (address << 1);

address &= ~(0x01); // clear LSB 0 = write

I2C1->CR1 |= (I2C_CR1_START | I2C_CR1_ACK);

while (!(I2C2->SR1 & I2C_SR1_SB)); // wait for start condition to be generated

I2C1->DR = address; //address is just sent on the line as data, after a start bit MSB first

//I2C1->CR1 |= (I2C_CR1_START);

while (!(I2C2->SR1 & I2C_SR1_ADDR));

status_register_1_read = I2C1->SR1; // these two reads clear addr

status_register_1_read = I2C1->SR2;

while (!(I2C2->SR1 & I2C_SR1_TXE));

I2C1->DR = message;

//I2C1->CR1 |= (I2C_CR1_START);

while (!(I2C2->SR1 & I2C_SR1_BTF));

I2C1->CR1 |= (I2C_CR1_STOP);

}

//----------------------------------------------------------------------

//                             Call of Transmit

//----------------------------------------------------------------------

ll_i2c1_transmit(0x55, 0x33);

/* USER CODE END */ 

/* USER CODE BEGIN 2 */

//----------------------------------------------------------------------

//                                      Clocks

//----------------------------------------------------------------------

//---------- Port for the LED and I2C --------------------------

RCC->APB2ENR |= RCC_APB2ENR_IOPAEN;

RCC->APB2ENR |= (RCC_APB2ENR_IOPBEN | RCC_APB2ENR_AFIOEN);

//----------------------------------------------------------------------------------------

void ll_clocks_enable_i2c1(void){

RCC->APB1ENR |= RCC_APB1ENR_I2C1EN;

}

 

//----------------------------------------------------------------------

//                                      GPIO

//----------------------------------------------------------------------

//I2C1 Alternate functions

GPIOB->CRH &= ~GPIO_CRH_CNF8;

GPIOB->CRH |= (GPIO_CRH_CNF8); //set 10 of the config bits

GPIOB->CRH |= GPIO_CRH_MODE8; // 50MHz output

GPIOB->CRH &= ~GPIO_CRH_CNF9;

GPIOB->CRH |= (GPIO_CRH_CNF9); //set 10 of the config bits

GPIOB->CRH |= GPIO_CRH_MODE9; // 50MHz output

 //----------------------------------------------------------------------------------------------------

void ll_gpio_remap_i2c1(void){

AFIO->MAPR |= AFIO_MAPR_I2C1_REMAP;

}

 /* USER CODE END 2*/