SOFTDEVICE: INVALID MEMORY ACCESS. error coming up while doing erase operation in NRF52832

[Srivisakh]

Hi,

I am using a custom NRF52832 board. I am using Nordic SDK + BLE code, and whenever I am trying to do an erase of flash memory with start address as 0x70000 and end address as 0x70100, I am getting "SOFTDEVICE: INVALID MEMORY ACCESS" error. I checked like whether I was trying to erase a memory area in the soft device protected area, but I found like the flash memory area does not belong to the softdevice protected region. 

Can you please guide me on how to resolve this issue.

I am using nrf_nvmc_page_erase() function to erase the flash memory area.

[AndreasF]

Hi.

You cannot use nrf_nvmc_page_erase() when you use the SoftDevice.

You have to use sd_flash_page_erase():

/**@brief Flash Erase page
*
* Commands to erase a flash page
* If the SoftDevice is enabled:
*  This call initiates the flash access command, and its completion will be communicated to the
*  application with exactly one of the following events:
*      - @ref NRF_EVT_FLASH_OPERATION_SUCCESS - The command was successfully completed.
*      - @ref NRF_EVT_FLASH_OPERATION_ERROR   - The command could not be started.
*
* If the SoftDevice is not enabled no event will be generated, and this call will return @ref NRF_SUCCESS when the
* erase has been completed
*
* @note
*      - This call takes control over the radio and the CPU during flash erase and write to make sure that
*        they will not interfere with the flash access. This means that all interrupts will be blocked
*        for a predictable time (depending on the NVMC specification in the device's Product Specification
*        and the command parameters).
*      - This call will make the SoftDevice trigger a hardfault when the page is erased, if it is
*        protected.
*
*
* @param[in]  page_number           Page number of the page to erase
*
* @retval ::NRF_ERROR_INTERNAL      If a new session could not be opened due to an internal error.
* @retval ::NRF_ERROR_INVALID_ADDR  Tried to erase to a non existing flash page.
* @retval ::NRF_ERROR_BUSY          The previous command has not yet completed.
* @retval ::NRF_ERROR_FORBIDDEN     Tried to erase a page outside the application flash area.
* @retval ::NRF_SUCCESS             The command was accepted.
*/
SVCALL(SD_FLASH_PAGE_ERASE, uint32_t, sd_flash_page_erase(uint32_t page_number));

Best regards,

Andreas

[Srivisakh]

Hi Andreas,

Thanks for the reply.

I tried using sd_flash_page_erase() function and was getting the error as "NRF_ERROR_INVALID_ADDR". I checked and provided the start address as 0x70000 in the nrf_fstorage_t's start_addr element, but still I was getting the invalid address error. 

Kindly give your insights on this issue.

[AndreasF]

Hi.

This function takes page number, so you have give page number as input and not start address.

Each page is 4kB, and your start address is 0x70000 which in kB is 458 752 in decimal which is 448 kB.

448 kB / 4 = 112.

Try to use sd_flash_page_erase(112);

Best regards,

Andreas