Writing data in flash

[Crescenzo Dassi]

Hello,

I am working in NCS and I am trying to save some data in flash before the SoC turns off.

I am starting by using the code below.

       //erase page 
       NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Een << NVMC_CONFIG_WEN_Pos;
       while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
       NRF_NVMC->ERASEPAGE = 0x0005A000;
       while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}

  
       //write data in flash's page
       NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
       while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
       *(uint32_t *)0x0005A000 =0x0000000AUL;
       NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
       while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}

If I use this code in the main() I can see the data written in flash. Instead, if I write the same code either in a gpio interrupt or in a thread, the SoC goes in Hard Fault and nothing is written in flash.

Can you help me to understand the problem?

Best Regards,

Crescenzo

[Simon]

I was not able to reproduce the hard fault. I ran your snippet from a thread and did not get any hard faults. I wrote 

0x0000009AUL to address 0x0005A000 and confirmed that it was sucessfully exectuted:

C:\Users\Simon>nrfjprog --memrd 0x00059FF0 --n 0x30
0x00059FF0: FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF   |................|
0x0005A000: 0000009A FFFFFFFF FFFFFFFF FFFFFFFF   |................|
0x0005A010: FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF   |................|

Could you test the same code and see if you get it to work:

threads_raw_flash.7z

Best regards,

Simon

[Crescenzo Dassi]

Hi Simon,

Your code works. However it starts breaking if you add some Bluetooth features. 

For instance, if in your project, in prj.conf you add the following configurations to enable the bonding

# Enable bonding
CONFIG_BT_SETTINGS=y
CONFIG_FLASH=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_FLASH_MAP=y
CONFIG_NVS=y
CONFIG_SETTINGS=y

and in the main you add:

        bt_enable(NULL);

     
	if (IS_ENABLED(CONFIG_SETTINGS)) {
		settings_load();
	}

The SoC goes in hard fault when attempts to write the flash in the thread.

I noticed that everything works fine if you remove CONFIG_NVS=y from prj.conf.

However, even without CONFIG_NVS,  if in the main you add a command to start the advertising, like below

        bt_le_adv_start(BT_LE_ADV_CONN, ad, ARRAY_SIZE(ad), sd,
			     ARRAY_SIZE(sd));

The SoC goes in hard fault again when trying to write in flash...

I don't understand the correlation between Bluetooth Stack and Memory Controller, but something happens when you try to handle both in the same code.

I attach the prj.cnf file I am working with.

.myprj.conf

Thank you.

Best Regards,

Crescenzo

[Simon]

A customer faced a similar issue recently: https://devzone.nordicsemi.com/support-private/support/269399#permalink=659970 Could you test the solution proposed there?

Best regards,

Simon