Projects for Writing into Flash Memory does not work on nRF52840 dongle

[shaileshbc]

I am using nRF52840 dongle and nRF SDK version nRF5_SDK_17.0.0_9d13099.

When I am trying to debug the application it gives an error.

using your example project on nRF52840 dongle

nRF5_SDK_17.0.0_9d13099\examples\peripheral\flash_fds\pca10056\s140\ses\flash_fds_s140_pca10056.emProject

main.c 

Line 352 rc = fds_record_update(&desc, &m_dummy_record);
after that it goes to
app_error_weak.c file , Line no. 100

nRF5_SDK_17.0.0_9d13099\examples\peripheral\flash_fstorage\pca10056\s140\ses\flash_fstorage_s140_pca10056.emProject

main.c

line no. 284 rc = nrf_fstorage_write(&fstorage, 0x3e100, &m_data, sizeof(m_data), NULL);
after that it goes to
app_error_weak.c file , Line no. 100

nRF5_SDK_17.0.0_9d13099\examples\peripheral\flashwrite\pca10056\blank\ses\flashwrite_pca10056.emProject

When trying to write hex file into the dongle, it does not allow to add softdevice hex file, stating that the hex file is overlapping.

if I try to write hex file flashwrite_pca10056.hex, it gives an error, log of the programmer is   2020-08-11T07_59_13.264Z-log.txt

do let me know, what I am missing.

[Amanda Hsieh]

Hi, 

Flash Data Storage Example needs to establish a UART connection, but the nRF52840 dongle there is no UART connected to the PC, other than the virtual COM port that is used for programming via Serial DFU (USB).

You should consider the nRF52840 DK instead if you want to develop firmware for the nRF52840. The nRF52840 dongle is primarily intended to be used together with nRF Connect for desktop and is not well suitable as a development board. This is primarily because it lacks an onboard debugger. 

-Amanda H.

[shaileshbc]

Hi Amanda,

Do you mean that if I do not establish a UART connection, I can't write in Flash Memory?

regards

Shailesh

[Amanda Hsieh]

Hi Shailesh, 

According to this softdevice specification, peripheral Id 30-> NVMC is a restricted peripheral when the softdevice is enabled. That means that it is not allowed to access NVMC registers directly from the application as those registered are inside access protected areas. And you can see in the implementation of nrf_nvmc_write_bytes that it is accessing NVMC registers directly, hence the memory fault. This post might help. 

-Amanda H.

[shaileshbc]

Hi Amanda,

In that case, it should also raise memory fault when I am running nrf_nvmc_write_bytes function, just after flash_page_init(), but it didn't raise any fault.

Fault is raised only, when i call nrf_nvmc_write_bytes function, after advertising_start() function in the example.

regards

Shailesh

[Amanda Hsieh]

Hi Shailesh, 

According to this softdevice specification, peripheral Id 30-> NVMC is a restricted peripheral when the softdevice is enabled. Therefore, it only happened to the nrf_nvmc_write_bytes function which is after your ble_stack_init().

-Amanda H. 

[shaileshbc]

Hi Amanda,

My main purpose is solved in writing data into Flash memory and sending it as advertising data.

Yesterday I come to know that the error which I was getting while debugging is due to the time taken to check the variable value and not related to coding.

It depends where I had added a breakpoint and how much time it takes to check and resume the execution of code.

if I take more time, then the error NRF_FAULT_ID_SD_ASSERT is raised.

You may close this ticket.

regards

Shailesh

[Amanda Hsieh]

Hi Shailesh, 

Great to know you find the root cause. 

Best regards,

-Amanda H.