STM32 & TLV5628 SPI Communication

Question

Hi Everyone and thank you for your time.

I have been working on interfacing the STM32f446RE Nucleo board with the TLV5628 8 Bit Octal Serial DAC. I have ran into multiple issues, but the current issue has been one of two things:

1) The data and clock lines showing the exact same information

or

2) The data line showing information, but nothing on the clock line.

Regardless, the information coming out is completely incorrect.

Here is my setup code:

void SPI_INIT(void){
// Enable clocks for C
    RCC->AHB1ENR |= RCC_AHB1ENR_GPIOCEN;

    // SPI GPIO
    GPIOC->MODER |= 2 << 3*2; // PC3 data pin
    GPIOC->MODER |= 2 << 7*2; // PC7 clock pin
    GPIOC->MODER |= 1 << 2*2; //pc2 load
    GPIOC->MODER |= 1 << 4*2; //pc4 ldac - probably set low permanently
    // Pins default to push-pull
    // set all to high speed
    GPIOC->OSPEEDR |= (3 << 2*2) | (3 << 3*2) | (3 << 4*2) | (3 << 7*2);
    GPIOC->AFR[0] |= 5<< 6*2; // Alt func 5 pc3 - SPI2
    GPIOC->AFR[0] |= 5 << 7*2; // Alt func 5 pc7 - SPI2
    // SPI Setup
    RCC->APB1ENR |= RCC_APB1ENR_SPI2EN; // Enable SPI Clock
    RCC->APB1RSTR |= RCC_APB1RSTR_SPI2RST; // reset SPI2
    RCC->APB1RSTR &= ~RCC_APB1RSTR_SPI2RST;// clear the reset

    // Control Register 1
    SPI2->CR1 &= ~SPI_CR1_SPE; // Disable SPI
    SPI2->CR1 |= SPI_CR1_MSTR; // master mode
    SPI2->CR1 &= ~SPI_CR1_RXONLY; // transmit, 0 == full duplex
    SPI2->CR1 &= ~SPI_CR1_DFF; // 8 bit format
    SPI2->CR1 &= ~SPI_CR1_LSBFIRST; // MSB first
    SPI2->CR1 &= ~SPI_CR1_CPOL;// low polarity, so 0 when idle
    SPI2->CR1 |=   4 << 3; // (180M/4)/32 = 1.41 MHz
    SPI2->CR1 |= SPI_CR1_CPHA; // first edge, look in data sheet
    //Questionable settings
    // Biderectional data line
    SPI2->CR1 |= SPI_CR1_BIDIMODE; // 1/17/2019 --> Check to see if this fixes something

    SPI2->CR1 |= SPI_CR1_BIDIOE; // idk if i need this
    //  CRC Polynomial Register
    SPI2->CRCPR = 10;

    // Control Register 2
    SPI2->CR2 |= 1<<2; // SS output enabled

    SPI2->CR1 |= SPI_CR1_SPE; // enable, has to be last
}

And here is my SPI Write code:

void SPI_Write(int dacSelect, int adcData){

    while((SPI2->SR & SPI_SR_TXE) != 0);
    GPIOC->ODR |= 1 << 2; // load set high to read data
    SPI2->DR = dacArray[dacSelect]; // send address
    SPI2->DR = adcData; // send adc data
  while((SPI2->SR & SPI_SR_BSY) == SPI_SR_BSY);
    GPIOC->ODR &= ~(1 << 2); // Send load low to load data
    Delay(10); // short delay
    GPIOC->ODR |= 1 << 2;
}

Gürtaç Kadem Gürtaç Kadem · Accepted Answer · 2019-01-21T18:54:03

You can use STMCubeMX to generate codes for STM microprocessors and boards. Following code blocks are generated from STM32ubeMX for STM32F4. You should change baudrate for your sensor.

SPI_HandleTypeDef hspi;
SPI_HandleTypeDef SpiHandle;

void Spi_Initialize(void)
{
    /*##-1- Configure the SPI peripheral #######################################*/
    /* Set the SPI parameters */
    SpiHandle.Instance               = SPI2;
    SpiHandle.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_256;
    SpiHandle.Init.Direction         = SPI_DIRECTION_2LINES;
    SpiHandle.Init.CLKPhase          = SPI_PHASE_1EDGE;
    SpiHandle.Init.CLKPolarity       = SPI_POLARITY_LOW;
    SpiHandle.Init.DataSize          = SPI_DATASIZE_8BIT;
    SpiHandle.Init.FirstBit          = SPI_FIRSTBIT_MSB;
    SpiHandle.Init.TIMode            = SPI_TIMODE_DISABLE;
    SpiHandle.Init.CRCCalculation    = SPI_CRCCALCULATION_DISABLE;
    SpiHandle.Init.CRCPolynomial     = 7;
    SpiHandle.Init.NSS               = SPI_NSS_SOFT;
    SpiHandle.Init.Mode              = SPI_MODE_MASTER;

    if(HAL_SPI_Init(&SpiHandle) != HAL_OK)
    {
        while(1){};
    }
}

void Spi_Read(void )
{
    uint8_t SpiData[2];
    uint8_t tempmessage = 8;

    HAL_GPIO_WritePin(GPIOG,GPIO_PIN_8,RESET); // CS pin

    HAL_SPI_TransmitReceive(&hspi,&tempmessage,SpiData,2,5000); // Read Data

    HAL_GPIO_WritePin(GPIOG,GPIO_PIN_8,SET); // CS Pin
}

void Spi_Write(uint8_t *Data, uint8_t size)
{   
    HAL_GPIO_WritePin(GPIOG,GPIO_PIN_8,RESET); // CS pin

    HAL_SPI_Transmit(&hspi, Data, size, 5000); // Write Data

    HAL_GPIO_WritePin(GPIOG,GPIO_PIN_8,SET); // CS Pin
}

STM32 & TLV5628 SPI Communication

2 Answers