Read values of UICR in Application

[Simon_89]

Hi, 

I am trying to read the value of the UICR register CUSTOMER[4] during the runtime of the application. Therefore, I am using the following code:

nrf_fstorage_read(&m_fs, (0x10001090), &destination, 32);

Where m_fs is the storage instance and destination is initialized as a char array.

My two questions are: 

- Is it correct to use nrf_fstorage_read for this purpose?

- Which address do I need to use, as my call is returning error 16: NRF_ERROR_INVALID_ADDR

Thanks, 

Simon

[JamesDougherty]

Are you using Zephyr? Here is how I did it in Zephyr. Hopefully it helps some.

I have an enum to easily select which UICR value I want to interact with:

typedef enum flash_uicr_register {
    fur_01,
    fur_02,
    ...
    fur_30,
    fur_31,
    fur_32,
} flash_uicr_register_t;

Then I wrote a simple helper function to easily compute the offsets:

static off_t compute_uicr_offset(const flash_uicr_register_t uicr_register)
{
    //
    // The UICR base address is 0x10001000
    // The UICR registers start at 0x080
    //
    // This calculation calculates the offset based off of the passed in register ordinal.
    //
    // Examples:
    //     fur_01: 0x10001000 + (0x080 + (0 << 2)) = 0x10001080 (0x080)
    //     fur_02: 0x10001000 + (0x080 + (1 << 2)) = 0x10001084 (0x084)
    //     fur_nn: ...
    //     fur_31: 0x10001000 + (0x080 + (30 << 2)) = 0x100010F8 (0x0F8)
    //     fur_32: 0x10001000 + (0x080 + (31 << 2)) = 0x100010FC (0x0FC)
    //
    // See: https://infocenter.nordicsemi.com/topic/ps_nrf52840/uicr.html
    //

    return (off_t)NRF_UICR + (0x080 + (uicr_register << 2));
}

 

Then I use the Zephyr's flash driver to interact with it. Here is a simplified version:

uint32_t flash_read_uicr(const flash_uicr_register_t uicr_register)
{
    __ASSERT_NO_MSG(uicr_register >= fur_01 && uicr_register <= fur_32);

    static uint32_t value = 0;

    int error = flash_read(mDevice, compute_uicr_offset(uicr_register), &value, sizeof(uint32_t));

    if (error != 0)
    {
        LOG_FLASH_E("Error reading from the UICR (Error: %d - %s)", error, errno_to_str(error));
        return false;
    }

    return value;
}

bool flash_write_uicr(const flash_uicr_register_t uicr_register, const uint32_t value)
{
    __ASSERT_NO_MSG(uicr_register >= fur_01 && uicr_register <= fur_32);

    int error = flash_write(mDevice, compute_uicr_offset(uicr_register), &value, sizeof(uint32_t));

    if (error != 0)
    {
        LOG_FLASH_E("Error writing to the UICR (Error: %d - %s)", error, errno_to_str(error));
        return false;
    }

    return true;
}

bool flash_write_verify_uicr(const flash_uicr_register_t uicr_register, const uint32_t value)
{
    return flash_write_uicr(uicr_register, value) &&
           flash_read_uicr(uicr_register) == value;
}

bool flash_erase_uicr(void)
{
    int error = flash_erase(mDevice, (off_t)NRF_UICR, sizeof(*NRF_UICR));

    if (error != 0)
    {
        LOG_FLASH_E("Error erasing the UICR memory (Error: %d - %s)", error, errno_to_str(error));
        return false;
    }

    return true;
}

Here is what mDevice is:

const struct device *const mDevice = DEVICE_DT_GET(DT_CHOSEN(zephyr_flash_controller));

[Simon_89]

Hi, 

I'm sorry, I'm still using the old framework, nrf5 sdk for thread and zigbee which in our case is used together with FreeRTOS

[JamesDougherty]

Hello,

No worries, I'll leave that there just in case someone asks about it and is using Zephyr / nRF Connect SDK.