SGP40 sensor

[er3481]

Hi

I am trying to read the SGP40 VOC sensor with the code below, but i can't read the raw data. I can transmit the command but when i try to receive data, it can not receive. I am using STM32F103 mcu. Any advise .

uint8_t SGP40_ReadVOC(void)
{
    uint8_t cmd[2] = {0x26, 0x0F};  
    uint8_t rx_buf[6];
    uint16_t voc_raw = 0;

    HAL_Delay(250);  

    if (HAL_I2C_Master_Transmit(&hi2c1, 0xB2, cmd, 2, HAL_MAX_DELAY) != HAL_OK)
    {       
        return 0xFF;
    }

    HAL_Delay(30);  

    if (HAL_I2C_Master_Receive(&hi2c1, 0xB3, rx_buf, 6, HAL_MAX_DELAY) != HAL_OK)
    {       
        return 0xFF;
    }

    voc_raw = (rx_buf[0] << 8) | rx_buf[1];

    return voc_raw >> 8;  
}

[Andrew Neil]

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@er3481 wrote:

the SGP40 VOC sensor

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You mean this: https://sensirion.com/products/catalog/SGP40 ?

Please give details of your hardware; show schematics.

Have you looked at the I2C lines with an oscilloscope and/or analyser to see what - if anything - is happening?

Are you sure you have the correct I2C address, and correctly shifted as HAL requires?