Using SD card on nRF9161 DK

[JOEBRE]

Hello, we've a nRF9161 DK board a we saw on the back side a footprint for mounting an SD card holder and we found the SD card holder component in the BOM.

Unfortunately there is no mention about the usage of the SD card in for the nRF9161 DK anywhere in the documentation.

Is there any problem on using the SD card on nRF9161 DK (trough SPI I guess) ?

What do we have to do to connect the SD card to the nRF9161 module (excluding the soldering of the card holder)?

Thanks in advance for the support,

Joel

[JOEBRE]

I was talking about J8 on the bottom side of the board listed on the BOM as "microSD Card Connector"...

[ketiljo]

What version of the DK do you have?

[JOEBRE]

Hello... I formatted no the SD card with a FAT filesystem (to get at leas a starting point) ... I will switch to LittleFS later once things are working... 

I'm using SDK v3.0.2 on visual studio code ith the v3.0.2 tool-chain. Looking at the README.rst description to build the usb mass storage it should be enough:

- create a new application using copy from sample (usb mass storage) sample 

- add a build configuration with Board target set to nrf9161dc/nrf9161

- at this point (to build for SD card with SPI interface ) the README requires to invoke the build with the option -DCONFIG_APP_MSC_STORAGE_SDCARD=y (which I suppose is defining the symbol CONFIG_APP_MSC_STORAGE_SDCARD and sets it to the value y). Since I'm calling the build directly from VSCode... how should I set CONFIG_APP_MSC_STORAGE_SDCARD to y ? directly in prj.conf ? using Kconfig GUI ? ... 

If I just build the application without any modification I get a compilation error stating:

C:/ncs/MyApp/mass_2/src/main.c:36:2: error: #error No supported disk driver enabled
   36 | #error No supported disk driver enabled

Same thing if I add CONFIG_APP_MSC_STORAGE_SDCARD=y directly to prj.conf.

What do I need to set to successfully build this sample for SD card on SPI interface with FAT filesystem on nrf9161DK ?

[JOEBRE]

Just to understand if there is something wrong with the sample or my SDK (v3.0.2 ) installation I generated a new mass storage project for nrf52840dk/nrf52840 (which is listed in the README file as a compatible board).

The sample doesn't build ... 

C:/ncs/v3.0.2/nrf/include/flash_map_pm.h:47:22: error: 'PM_storage_partition_ID' undeclared (first use in this function)
   47 | #define PM_ID(label) PM_##label##_ID

...

How shall I proceed to get this sample be configured and build correctly ?

Joel

[Edvin]

Hello,

Yes, I noticed that now. It built fine before v2.7.0, when sysbuild was introduced. Since it is in the zephyr part of NCS, we do not have direct control over these samples, so not all of them work out of the box.

I got it running for the nRF52840 DK by adding this pm_static.yml file to the application folder:

storage_partition:
  affiliation: disk
  extra_params: {
      disk_name: "littlefs",
      disk_cache_size: 4096,
      disk_sector_size: 512,
      disk_read_only: 0
    }
  address: 0xfa000
  end_address: 0x100000
  placement:
    before:
    - end
  region: flash_primary
  size: 0x6000

(I was not allowed to upload .yml file, but you can take this one, and rename it "pm_static.yml"

Fullscreen 4578.pm_static.txt Download

storage_partition:
  affiliation: disk
  extra_params: {
      disk_name: "littlefs",
      disk_cache_size: 4096,
      disk_sector_size: 512,
      disk_read_only: 0
    }
  address: 0xfa000
  end_address: 0x100000
  placement:
    before:
    - end
  region: flash_primary
  size: 0x6000

Then, you must build using the build command: west build -d <board name> -d build -- -DCONFIG_APP_MSC_STORAGE_SDCARD=y

as described here:

https://docs.nordicsemi.com/bundle/ncs-latest/page/zephyr/samples/subsys/usb/mass/README.html#sd_card_example

Best regards,

Edvin

[JOEBRE]

Hello, thanks... this explains a lot of things... with your input I'm now able to build LittleFS for nRF52840 too.

Question about the pm_static.yml you provided ... doesn't  "region: flash_primary" means that you're placing the storage_partition into the main flash instead of the desired external SD flash ? 

I tried the format sample by substituting LittleFS with FAT_FILESYSTEM_ELM and it is working perfectly using "SD:"as ID ... the issue is related to the usage of LittleFS.

Joel

[Edvin]

I am sorry, but I have not played around too much with SD cards in Zephyr/NCS. Did you test it? Does it actually use the SD card? 

I would test it, but we are very limited on resources right now, due to summer holiday season in Norway, and I don't think I will be able to set aside the time to test it before leaving in two days. 

If there is no SPI activity on the SD card gpios, can you compare the behavior with NCS v2.6.X? There the sample built without any modifications. Alternatively, you can reach out to the Zephyr support forum, as the SD card library is really not maintained by Nordic Semiconductor.

Or, I can have a look when I return in end of July. I am terribly sorry for the inconvenience!

Best regards,

Edvin