Log to nrf52 thingy internal flash

[spoerk]

I am working on a prototype using the nRF Connect SDK v2.1.0 on the nRF52 Thingy platform.

For my prototype, I need to store normal log output on the internal flash of the nRF52 Thingy in FAT format. The reason behind this is: I will put my Thingys in a testing environment to collect data. After some days, I want to collect the Thingys and read the log data via USB.

What is the best way to implement that?

I have been trying the https://docs.zephyrproject.org/latest/samples/subsys/usb/mass/README.html#fat-fs-example, but the FLASH configuration does not work (not on the Thingy and not on the nRF52840DK platform).

Best regards,

Michael

[Simon]

Hello Michael

I tried running buildining the sample \zephyr\samples\subsys\usb\mass in NCS v2.1.0 and flashing it to the nRF52840DK v3.0.0 but did not encounter the issue you did.

I got the following RTT output:

[00:00:00.255,645] <inf> main: No file system selected
[00:00:00.255,737] <inf> main: The device is put in USB mass storage mode.

and the following serial output:

*** Booting Zephyr OS build v3.1.99-ncs1  ***
[00:00:00.255,645] <inf> main: No file system selected
[00:00:00.255,737] <inf> main: The device is put in USB mass storage mode.

Try running nrfjprog --qspieraseall first, and program the USB Mass sample again.

Best regards,

Simon

[spoerk]

Hi Simon, 

Thank you for your fast reply. As far as I can tell, you run the sample without specifying a file system. ("No file system selected" in the RTT output.

Here is my full prj.conf content:

CONFIG_STDOUT_CONSOLE=y

#USB related configs
CONFIG_USB_DEVICE_STACK=y
CONFIG_USB_DEVICE_PRODUCT="Zephyr MSC sample"
CONFIG_LOG=y
CONFIG_USB_DRIVER_LOG_LEVEL_ERR=y
CONFIG_USB_MASS_STORAGE=y
CONFIG_USB_DEVICE_LOG_LEVEL_ERR=y
CONFIG_USB_MASS_STORAGE_LOG_LEVEL_ERR=y

CONFIG_MAIN_STACK_SIZE=1536

CONFIG_APP_MSC_STORAGE_FLASH_FATFS=y

I have executed nrfjprog --qspieraseall, but it did not solve the problem.

Best regards,

Michael

[spoerk]

Thanks that fixed the problem.

I have created a Zephyr issue so that this will get fixed in the future (https://github.com/zephyrproject-rtos/zephyr/issues/51720). Thanks.

[spoerk]

Do you by any chance know, how to configure the Zephyr FAT FS so that I can mount it on Windows without needing to format it?

With your fix, I am able to mount it, but I think the config is wrong. When I format it in Zephyr, Windows cannot read it. When I format it in Windows, Zephyr cannot read it.

I could not find anything about FAT configuration for Windows compatibility in this forum.

All the best,

Michael

[Sigurd Hellesvik]

Hi Michael,

I know windows has a limited set of supported filesystem formats.
My best guess is that you will need to figure out if windows supports FAT at all, and then what specific settings windows needs for FAT.

I do not think we have anything on this, but I can try to look a bit more into it in the next couple of days.

Regards,
Sigurd Hellesvik

[Sigurd Hellesvik]

A colleague gave me an idea:

The fat_fs sample worked for them, but they formatted the SD card on the windows first, then used it with the nRF.

Would this work for you?
To format it with windows first and then use it.

Regards,
Sigurd Hellesvik

[spoerk]

Thanks for getting back that fast.
Unfortunately, formatting the FAT filesystem with Windows first does not fix the problem.

The firmware on the nRF52 detects that the filesystem configuration (perhaps the block size) is not correct and formats the filesystem again with its parameters.

Do you know of a filesystem config (e.g., block size, sectors, ...) windows and Zephyr can read?

Thank you,
Michael

[ovrebekk]

Hi Michael

Sigurd is currently on leave, so I will help you with this case. 

Just for my own curiosity, how are you planning to read data over USB from the Thingy52? 
The Thingy52 uses the nRF52832, which doesn't support USB, and the USB port on the board is used for charging the device only. 

I did some testing myself, and using an nRF52840DK I have no issues to format the disk in Windows and access it locally, but so far I have only tested using the MX25 QSPI flash device on the DK. Are you able to share the project you are using to set up the internal flash rather than the external one? 

Then I can test it locally, and see if I can reproduce your issue. 

Best regards
Torbjørn

[spoerk]

Hi Torbjørn,
Thanks for the reply. Yes, I was planning to use the USB on the Thingy52, but silly me did not read the documentation or looked at the schematics. Thank you for clarifying that my planned USB logging is not possible on the Thingy 52 hardware. 

Sorry to keep you busy with my issue. I should have checked before.

All the best,

Michael

[ovrebekk]

Hi Michael

No worries, it happens to the best of us

The Thingy53 and Thingy91 have proper USB support, if you ever switch to one of them. 

How to handle it best on the Thingy52 I don't know. Potentially you can still store it in flash directly, and use a debugger to read it out. Or connect to the UART interface and add some function to dump the logs over UART. 

Best regards
Torbjørn