AD7771 STM32 sample project example

Hi Aalakh ,

Attaching the example code. I hope this helps.

ad777x_iio-application.zip

I am using no_os ad7779 driver with STM32H745 MCU

Facing following issues in stm32_spi.c source file.

'SPI_CR1_BR_Pos' undeclared (first use in this function); did you mean 'SPI_CFG1_MBR_Pos'?

'SPI_SR_RXNE' undeclared (first use in this function); did you mean 'SPI_SR_RXWNE'?

'SPI_SR_TXE' undeclared (first use in this function); did you mean 'SPI_SR_TXP'?  

'SPI_TypeDef' has no member named 'DR'; did you mean 'SR'?    

Macros are not defined in stm32h7xx_hal.h

DR is not a member in SPI_TypeDef

Can you please check and confirm whether these drivers supports stm32H7 platform

Hi Aalakh ,

I believe the drivers do not support the STM32H7 platform.

But as a temporary solution, the macro SPI_CR1_BR_Pos can be replaced with the  SPI_CFG1_MBR_Pos.

The stm32_spi_write_and_read() function can be replaced with the following:

int32_t stm32_spi_write_and_read(struct spi_desc *desc,
                 uint8_t *data,
                 uint16_t bytes_number)
{
    int32_t ret;
    struct stm32_spi_desc *sdesc;
    if (!desc || !desc->extra || !data)
        return -EINVAL;
    if (!bytes_number)
        return 0;
    sdesc = desc->extra;
    ret = gpio_set_value(sdesc->chip_select, GPIO_LOW);
    if (ret < 0)
        goto error;
    ret = HAL_SPI_TransmitReceive(&sdesc->hspi, data, data, bytes_number,
                      HAL_MAX_DELAY);
    if (ret != HAL_OK) {
        if (ret == HAL_TIMEOUT)
            ret = -ETIMEDOUT;
        else
            ret = -EIO;
    }
error:
    return gpio_set_value(sdesc->chip_select, GPIO_HIGH);
}

Hi can you provide conversion of raw ADC counts to input voltage formula for bipolar input configuration?

Hi Aalakh ,

The data output format for this part is Two's complement. The following thread might help more on this.

ez.analog.com/.../445512

Right now it is developed for polling method. 

Do you have driver with DMA method or any suggestion to make it work with DMA

Aalakh - we do not have this implementation using SPI DMA.

The TDM Mode in this code works with the support of DMA

Aalakh - we do not have this implementation using SPI DMA.

The TDM Mode in this code works with the support of DMA