Write in flash + re-init problem

RE: Write in flash + re-init problem

Jørgen Holmefjord — Wed, 31 Oct 2018 14:55:44 GMT

Yes, that could explain the behavior.

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 14:26:47 GMT

Oh gosh, I think I just found the mistake, I interverted to letters in memory address (0x33AC0 => 0x33CA0)

RE: Write in flash + re-init problem

Jørgen Holmefjord — Wed, 31 Oct 2018 14:14:24 GMT

Did you pass the address itself to sd_flash_page_erase? Note that this function take the page_number as parameter. The page size in nRF51822 is 1024 bytes. Have a look at this answer for conversion from address to page.

Please always remember to check the error codes from function calls. It looks like you are not doing this on call to sd_flash_page_erase in your code posted before. Most likely this function will report an error if you pass an invalid address.

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 14:09:51 GMT

Maybe I can post here the init function, main, UART command processing function & write in flash function it that can help

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 14:03:06 GMT

I did, erase did not seem to work, still 00 00 00 00 at this memory location

RE: Write in flash + re-init problem

Jørgen Holmefjord — Wed, 31 Oct 2018 13:58:35 GMT

Removing calls to advertising/scan start should be sufficient.

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 13:54:31 GMT

What do I need to do to achieve that ? Remove all inits but keep only softdevice_sys_evt_handler_set(sys_evt_handler) + timer_init + SOFTDEVICE_HANDLER_INIT ?

RE: Write in flash + re-init problem

Jørgen Holmefjord — Wed, 31 Oct 2018 13:46:10 GMT

Yes, this is correct. Can you try the code that you use for erasing with all BLE activity deactivated (no advertising/scanning/connection, but softdevice still enabled)?

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 13:43:44 GMT

Seems that the flash is never erased, I still have 00 00 00 00 at this address, when I erase I should get FF FF FF FF if I am right

RE: Write in flash + re-init problem

Jørgen Holmefjord — Wed, 31 Oct 2018 12:39:02 GMT

Put an infinite while loop (while(1)) after the erase and check the flash with nrfjprog.

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 12:33:57 GMT

I just tried to put a breakpoint before erasing flash, I do not know why but Keil does not let me put a breakpoint there, so I think the erase is not done, maybe that could be the problem, I cannot erase => I cannot write again in flash. But I do not know why I cannot put a breakpoint there or why this part of code cannot be run

RE: Write in flash + re-init problem

Jørgen Holmefjord — Wed, 31 Oct 2018 12:28:17 GMT

It could, but then you should not receive a SUCCESS event. Did you try reading the flash area after erase operation but before write operation?

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 12:14:44 GMT

Yes, I do the exact same thing when I erase a page, I wait for NRF_EVT_FLASH_OPERATION_SUCCESS, then I try to write again, waiting for the same event to be triggered, I was suspecting BLE activity could maybe interfere when I try to write in flash, could it be that ?

RE: Write in flash + re-init problem

Jørgen Holmefjord — Wed, 31 Oct 2018 12:08:45 GMT

Are you waiting for the SUCCESS even when erasing as well? Note that erasing a page can take a long time, especially if there are BLE activity going on at the same time.

RE: Write in flash + re-init problem

NicoH — Wed, 31 Oct 2018 10:24:56 GMT

I have already kinda done that with Keil & "Memory" section while in debug mode and the value did not change. I tried it with nrfjprog but got same results, when I erase & reflash all (including SoftDevice), if I read at this address, I have FF FF FF FF which is normal. Then I run the program once and set the default value at this memory location which is 00 00 00 00, that works.

After that, I cannot change the value anymore, I try to erase it first then write the new value but that does not seems to work.

RE: Write in flash + re-init problem

Jørgen Holmefjord — Tue, 30 Oct 2018 15:59:22 GMT

Can you read the memory location you are writing before and after writing it? You can do this using nrfjrpog with the command --memrd <addr>

RE: Write in flash + re-init problem

NicoH — Tue, 30 Oct 2018 14:34:49 GMT

Nothing really happens, the status code is ok (NRF_SUCCESS), after the write has been done I restart the device with NVIC_SystemReset, but value in flash is not modified, therefore I start again with the exact same mode.

So no particular error code, the address location is 0x00033AC0 which corresponds to the beginning of a page (page size is 1024)

RE: Write in flash + re-init problem

Jørgen Holmefjord — Tue, 30 Oct 2018 14:25:25 GMT

What happens when you try to write flash again? Do you get any error codes etc.? What address is the location you are trying to write?

RE: Write in flash + re-init problem

NicoH — Tue, 30 Oct 2018 14:16:20 GMT

I used nRFgo Studio to erase all and flasing again SoftDevice, then Keil for the application.

When I try to write in flash, I start by erasing the corresponding page first

flashBusy = true;
sd_flash_page_erase(DEVICE_TYPE_PAGE);
    
// Wait end erase flash page
while(flashBusy)
{
    sd_app_evt_wait();
}

I run this code before writing in flash, the flashBusy variable is reset by the sys_evt_handler callback on NRF_EVT_FLASH_OPERATION_SUCCESS .

It is not planned to write oftenly to flash, but for now, I cannot change the default value, it is pretty weird because I had the behaviour I wanted once but since then I cannot reproduce it anymore, really do not know why

RE: Write in flash + re-init problem

Jørgen Holmefjord — Tue, 30 Oct 2018 14:08:48 GMT

You should be able to write the location in flash once after erasing the page. Did you run --eraseall command using nrfjprog? If you only erase the flash are used by softdevice and application, this will not erase the are where your application wrote to flash. If you need to update the information in flash, you need to change the location where it is stored, or erase the flash page where the address is located. If you are planning to write often/much data to flash, I would recommend looking into FDS.

RE: Write in flash + re-init problem

NicoH — Tue, 30 Oct 2018 13:42:54 GMT

Well in fact I am running into another issue which I do not understand at all, I managed to get the desired behaviour once, and now, nothing works at all, the program cannot write in flash at the specified address, I really do not know why.

I tried to erase all in the device then re-flash the SoftDevice & application but it does not work anymore, I can write in flash the first time I run the program (I write at init the default mode) but after that, I cannot do it again it seems

RE: Write in flash + re-init problem

NicoH — Tue, 30 Oct 2018 13:18:04 GMT

I was at first trying to use it from interrupt context and figured out it was not working so I changed that and now I trigger the Flash write in main context. I identified the problem I think, in my function which processes the UART command received, I sent again some debug information on same UART so I was trigerring a new interrupt which caused the write in flash to fail.

Now I am able to write in flash & change the mode as I wanted, I just have another issue but I do not think it is related to this one, I guess it is due to bad behaviour in uart_event_handle function in different mode, I have to go check this out

RE: Write in flash + re-init problem

Jørgen Holmefjord — Tue, 30 Oct 2018 13:02:18 GMT

Most drivers/libraries have uninit functions. In most cases you should be able to reuse the initialized peripherals without re-initialization.

Are you triggering the Flash write from interrupt context or main context? Have you tried debugging the application to see if it gets past the while loop where you call sd_flash_write?

RE: Write in flash + re-init problem

NicoH — Tue, 30 Oct 2018 12:26:44 GMT

Hi Jorgen,

thank you for your answer, I figured out that I could not init the UART twice, same with BLE stack & other init functions, how to uninit those ?

I also tried something else, instead of trying to re-init, I change the device mode & write the new mode in flash, reset the device & then init with the new mode but I have some issues trying to write in flash. Indeed, when the device receive the UART command to change its mode, a flag is set to 1 & in the main function, when this flag is set, I try to write in flash the new mode & then reset the device but writing to flash fails, the program waits for NRF_EVT_FLASH_OPERATION_SUCCESS which never happens.

I do not understand pretty well this behaviour, I guess the sys_evt_handler callback is never called to trigger this event but I am not sure and i do not know why either.

Regards,

Nicolas Hell.

RE: Write in flash + re-init problem

Jørgen Holmefjord — Tue, 30 Oct 2018 11:56:54 GMT

Hi,

If you have already initialized UART, you will get INVALID_STATE error if you try to init it again. You either need to uninit the old initialization before re-init, or use the old initialized UART interface.

Best regards,
Jørgen