Flash can't not erase and write when a table in code

[gandyhuang]

hi

i use the example flashwriting in nRF5_SDK_15.3.0_59ac345, i set a table at 0xfd000:

// ProgramSection alignment="4" keep="Yes" load="yes" name=".tabletest" address_symbol="__tabletest_start" end_symbol="__tabletest_end"  start="0x000fd000" size="0x1000"

uint8_t const testtable[] __attribute__((section(".tabletest"))) __attribute__((used))={0xff,0xff,0xff,0xff}; 

//the test code in main.c 

uint8_t const testtable[] __attribute__((section(".tabletest"))) __attribute__((used))={0xff,0xff,0xff,0xff};
int main(void)
{
    uint32_t err_code;

    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));

    err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);

    err_code = clock_config();
    APP_ERROR_CHECK(err_code);



    flash_page_init();
    nrf_nvmc_write_word((uint32_t) &testtable,0);             //wirte 0xfd000 fail
    nrf_nvmc_page_erase((uint32_t) &testtable);               //erase 0xfd000 fail

but the if don't load the table 1st, it can work well

// ProgramSection alignment="4" keep="Yes" load="No" name=".tabletest" address_symbol="__tabletest_start" end_symbol="__tabletest_end"  start="0x000fd000" size="0x1000"

uint8_t const testtable[] __attribute__((section(".tabletest"))) __attribute__((used))={0xff,0xff,0xff,0xff};
int main(void)
{
    uint32_t err_code;

    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));

    err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);

    err_code = clock_config();
    APP_ERROR_CHECK(err_code);



    flash_page_init();
    nrf_nvmc_write_word((uint32_t) &testtable,0);             //wirte OK
    nrf_nvmc_page_erase((uint32_t) &testtable);               //erase Ok

so, why it's can't write and erase when set

load="yes" ?

[Simonr]

Hi

There are a few details I need from you.

• What device are you seeing this issue on? nRF52832 or nRF52840?
• How do you see that the write and erase fail? Is there any error code that might help us see what's causing this?
• Can you try to explain what exactly you want to achieve with this?

It seems to me like using the fstorage example instead might be easier, as that is a more "user-friendly" example.

Best regards,

Simon

[gandyhuang]

HI Simonr,

I tested it in nrf52840 , your can find the code and some picture in attached file; 

I have one project, there are some config data tables, and the data can be modified by app, but when i try to modify the data, i found that the the data had no any change, so i try test in flashwrite sample , but it still the same result.  I had checked the ACL register ,but all of ALL register is 0, Is there any other register do protect  the code size ?

flashwrite.zip

[Simonr]

Hi

Sorry about the delayed reply, but I was out of the office last Friday.

gandyhuang said:

I had checked the ACL register ,but all of ALL register is 0, Is there any other register do protect  the code size ?

 I'm sorry, but can you try to specify what it is you want to achieve with your project, as I'm having some trouble understanding what exactly you want to do. I need some more information regarding the goal of your project in order to help you.

Best regards,

Simon

[gandyhuang]

Hi,

I'm sorry, the description is not clear：I mean is there any other registers like ACL-Access Control Lists,Because I had checked NRF_ACL registers is set to 0x00, not block flash read or write; but flash page in 0xfd000 is still can not be write and erased when

load="yes"(see the flash_placement.xml)

 Can you help to check my code in attachments is correct？

[Simonr]

Hi

I can't see anything wrong right off the bat with your main file. Have you made any other changes than adding the .testtable and the write/erase commands to the main.c file? Please double check that you've configured the flash_placement.xml file correctly as well. This is very well described by a SEGGER employee in this case.

Best regards,

Simon