is it possible to hook an SD card to the Arduino uno q to create more storage
Hi @jade2031. Yes, it is possible.
The first thing to consider is: where do you need the storage? The UNO Q has a hybrid architecture where the board has a Qualcomm Dragonwing QRB2210 microprocessor running a Linux machine, and an STMicroelectronics STM32U585 microcontroller running your sketch program. An SD card can be connected to either of these.
Using Card via Microcontroller
If you wish to store data that is produced by the sketch program (e.g., sensor readings), and doesn't need to be processed by an application on the Linux machine, then you would probably want to connect the SD card to the SPI pins of the microcontroller, and work with the SD card via your sketch.
Using Card via Linux Machine
Conversely, if you wish to use the drive to increase the storage space available to the Linux machine, then you should connect the SD card to the microcontroller. This would be done by inserting the card into any USB SD card reader dongle (which can be purchased from any of the usual online marketplaces or other sources of computer equipment for a low price), then connecting that SD card reader to the UNO Q via a USB-C hub. Some USB-C hubs even have an integrated SD card reader. If you are using the UNO Q in single-board computer (SBC) mode, you can access the drive via the File Manager. You will see an item for the connected drive on the left hand panel of the File Manager window. It will be automatically mounted when you open the drive in File Manager. If you want to access the drive via the terminal, you can mount it using the mount command:
Although an SD card is specially suited for working with via the microcontroller, this is not the case with the Linux machine. You can use any type of external storage from the Linux Machine in the same manner as I described with the SD card in a USB card reader. If it is more convenient, feel free to use a flash drive or external USB drive instead of an SD card.
Note that there is nothing special to the UNO Q about working with external storage devices from the Linux machine. Information you find on the Internet that is general to Linux will also be applicable to the UNO Q. So if you are doing research on the subject, don't "poison" your searches by including keywords like "UNO Q" in your search queries.
I have provided a general overview of the subject. If you would like more specific assistance, we would need details about exactly what you are trying to accomplish. So if you give it a try and get stuck, feel free to come back and provide more information. We'll be happy to help you further.
the way I would be using it would be in SBC mode, so I would need more storage than just 16 GB so I thought that I could expand the storage via an SD card.
Running in SBC mode, maybe try a USB thumb drive in your hub..
haven't tried it myself but can't see any reason it wouldn't work..
good luck.. ~q
OK, great. So you will want to use the information I shared under the "Using Card via Linux Machine" section of my previous post.
As @qubits-us said, just connect any external USB drive to the USB-C hub attached to your UNO Q, then mount the drive. You will then be able to use it for storage, just the same as you would if using the drive with any standard consumer PC. This includes an SD card plugged into a USB card reader.
If you have an application where manually mounting the drive each session is inconvenient/infeasible, you can configure the operating system to automatically mount the drive on boot. From the desktop, you can do that by selecting Applications > Settings > Removable Drives and Media. A dialog will then open that allows you to configure the operating system to automatically mount external drives when connected and/or "hot plugged" (meaning connected to the USB socket while the operating system is running rather than being present at boot time).
You can also accomplish the same via a lower level configuration interface if you like:
Thank you, I really needed to know that.
You are welcome. I'm glad if I was able to be of assistance.
Regards, Per
After a long of hesitation, I have finally operated my UNO Q in SBC Mode, and it is working fine.
I have a transcend USB Mobile hard disk. Should I connect it with my 1-to-11 dongle to see if I can detect it from Linux OS and perform read/write operation? The capacity of my DC adapter is: 5V/3A. Presentlly, I have the dongle, Keyboard, Mouse and HDMI TV connected together.
Go for it! 
I am at Computer - Thunar window. Where should I browse to locate my hard disk?
Do you see an entry for the drive in the left hand panel of the window?:
https://docs.xfce.org/xfce/thunar/using-removable-media#accessing_removable_media
I expected that the hard disk will appear under the computer in the same way it comes in Windows. Now, I see it is different. I will play tomorrow. Now, it is 1:27 am in my Country and I am going to bed. Good night!
just hooked up a usb thumb drive, had to mount it manually..
used lsblk command to identify the partition for me it was sda1
then create a mount point..
sudo mkdir /mnt/usb_drive
then mount drive..
sudo mount /dev/sda1 /mnt/usb_drive
now in Thunar, goto File System, mnt and you should have a usb_drive folder..
fun stuff.. ~q
I have the same message in my preferences, but I don't have any problem mounting a USB thumb drive or SD card in USB card reader in Thunar.
When the drive is connected to the USB-C hub, there is an entry for it in the left hand panel of the File Manager (Thunar) window. When I click on that entry, the drive is mounted and opens in the file manager.
What problem did you encounter when you tried to mount the drive using Thunar @qubits-us?
nothing seemed to change in Thunar when I plugged the drive in..
saw the drive flash a bit..
closed Thunar and re-launched, nothing new..
was able to mount the drive manually and works fine..
kind of figured the missing deps had something to do with it..
i'll leave it in, see what happens in the morning..
it appears i was missing thunar-volman, just installed it so that may clear it up, all kinds of options inside of it regarding removable media..
strange.. ~q
booted up this morning..
nothing new in Thunar and my /mnt/usb_drive folder is empty..
manually mounted it worked..
then back into Thunar and the missing gvfs..
installing the gvfs and all it's backend dependencies said it was going to cost me about 100mb of space which is quite expensive on my 2gb with only a little over 900mb free..
but in the end i still have 887mb free so really didn't cost allot and what i've gained is amazing..
not only did i get removable storage working but also network functionality is working, i can connect to SMB shares on my various window systems..
my desktop changed as well..
note, had to reboot after installing all the gvfs..
sweet.. ~q
Now my 4g showed the drive straight away..
Some of the gvfs items are already installed..
I installed the missing gvfs items and picked up the networking..
Must depend on Linux core version..
~q
I have the latest OS image installed on my UNO Q:
$ cat /etc/buildinfo
BUILD_ID=20260407-523
VARIANT_ID=xfce
And it is fully updated.
mines older..
20251111-426
not sure about the 2g, i'll check it later..
the 2g didn't have any of the gvfs installed so no removable media or networking..
the 4g had removable media but no Network category below Devices in the left pane of Thunar..
It was just missing a few gvfs items adding them gave me the Networking..
and I no long have the message about gvfs not being available..
now in the Thunar address bar I can do a smb://192.168.1.3/ and it prompts me for credentials and connects..
nice.. ~q