Wireless USB storage stick? (SOLVED) - Page 1
Forum section: electronics / general

author: edy
author_rank: Super Contributor
timestamp: November 20, 2020, 01:31:13 pm
content: Hi,I was wondering if anyone had any experience with a USB memory device with WiFi that can either deposit files directly into a network share drive or could be accessed over the office WiFi to pull files off of it in real-time? This would be used for something like this USB-memory recording data logger:Normally I could remove the USB stick every day and copy the files over, but it would be easier if the data being written to the USB would just "auto-magically" be copied over to a spot on my server. Then I could even write a script to email the file to me hourly or scan the contents for a trouble condition and get notified. I guess if I am able to access the USB memory stick via WiFi I could make a Windows script that copies contents from the drive hourly and over-writes it to a directory on the server, so it has the most recent log saved for analysis (via other scripts). Thanks!Are there cheaper options available that are reliable, any brands or types to avoid? Are they easy to configure (how do you set them up, do you connect them to a regular computer first to set up the Wifi access point, username, password or is there a config file you copy over to the stick)?

author: David Hess
author_rank: Super Contributor
timestamp: November 20, 2020, 06:31:05 pm
content: They make or made SD and CF cards which did something like that to add WiFi capability to cameras which did not support it natively. I lost interest in them when they all relied on Cloud services.A Raspberry Pi can be used in USB OTG mode to act as a flash memory device to some other master. Then a script on the Raspberry Pi could transfer data over WiFi to a remote server.

author: PeteH
author_rank: Unknown
timestamp: November 20, 2020, 06:36:30 pm
content: SanDisk connect?Edit: likely not going to work as you want it to.Pi is a good option

author: edy
author_rank: Super Contributor
timestamp: November 21, 2020, 11:45:53 pm
content: I was hoping that the USB memory WiFi stick would have some kind of configuration file that can be put on it that basically has whatever information is required for it to connect to the local WiFi (SSID to connect to, type of security key and password for example) and then you'd look on your network for the IP address (say 192.168.x.x) and it would bring up some kind of file-access mechanism (even an HTML-based application).For example, when I hook up a WiFi printer all I do is connect to my WiFi by selecting the SSID and entering a password on the printer, and a config program on my PC just scans and finds the printer and sets the driver to point to the proper IP (192.168.x.x).When I connect my phone to my computer for WiFi-file transfer, I open up an app on the phone and start it's WebDAV function. It shows me the IP it's connecting to on my local network and I just go there with my PC's web-browser and I can see the directory folders and files. I can download stuff at the bare minimum. Some apps also have a button that let's me upload.Is there no USB storage WiFi stick that can even do basic functionally like that to connect to a PC?UPDATE:I found the following information, I will try and see if I can get it to work. I managed to get my hands on a few SanDisk Connect Wireless Sticks from an office that didn't use them anymore:https://kb.sandisk.com/app/answers/detail/a_id/3448/~/connecting-to-a-sandisk-connect-wireless-flash-drive-without-using-an-appApparently I can use the app to configure the stick first by connecting to it's WiFi access point first, then setting it to connect to my office WiFi network, noting it's IP address and then once it's connected to my office I should be able to access it through the web. Then it's a simple matter of running a "wget" script to download the file if I can acquire the URL of the log file. Will have to experiment with it... apparently it can be done without any apps or cloud services.

author: edy
author_rank: Super Contributor
timestamp: November 22, 2020, 12:49:57 am
content: Quote from: PeteH on November 20, 2020, 06:36:30 pmI was also doubtful, but after some playing around with it.... I managed to get it to work! (SanDisk Connect Wireless Stick Model: SDWS4 16GB). I don't think they sell this smaller version anymore, I only see 32GB - 256GB options now (https://www.sandisk.com/goto/connect). They are pricey! A link from SanDisk to the Amazon store lists the 32GB option for $95, the 64GB for $145, and 128 GB for $170 (https://www.amazon.com/gp/product/B00ZCFYF2W)! I'm glad I got these for free from the other office (they had them thrown in a box with a bunch of data-loggers as they decided to just hook up small printers instead to print out the data on-the-fly).I had to download an app to my phone (SanDisk Connect) and then connect to the drive first directly over WiFi (it shows up once you turn it on). Then once you connect to the drive in the app, you can activate an internet connection for the drive... at that point I select my office/home WiFi from the list, give it my password and then the drive is connected!Then I go into the "Settings/About" screen for the drive in the App and it lists the IP address (in my case it hooked in at 192.168.2.196). To access the files from my Linux machine all I had to do was navigate with my web-browser to:http://192.168.2.196/filesAnd if I want to download a file I can just find the URL by right-clicking on the link, for example the log for the data recorder was:http://192.168.2.196/cache/16C55E8ADEADBEEFFEEDFACEDEADBEEF00000000000000000000000000000000/files/RECORDER.TXTSo as far as I know, that should stay persistent as long as everything is connected the same way and I was able to download like this:wget -q "http://192.168.2.196/cache/16C55E8ADEADBEEFFEEDFACEDEADBEEF00000000000000000000000000000000/files/RECORDER.TXT" -O "log.txt"(The above will in quiet mode, download the file and overwrite it to log.txt so I could potentially put this into a cron or in Windows set up a scheduled event and have it continuously download the log file).

author: edy
author_rank: Super Contributor
timestamp: November 23, 2020, 05:23:15 pm
content: Just a quick note...I was testing out the SanDisk Connect Wireless Stick today with a datalogger and while I am able to set it up to work, there is a MAJOR inconvenience issue with it. It will *NOT* allow access to the drive while it is connected in USB Mode to read/write data, say on a computer or datalogger.That means, to be able to actually access the contents of the stick via WiFi, the datalogger has to be turned OFF manually each time. The only convenience here is that I don't have to physically unplug the stick. I can switch off the datalogger, copy over the log files through WiFi, and then switch the datalogger back on. Or whoever is using the machine has to remember to turn on/off the datalogger before/after each cycle.This is kind of a pain in the arse. I don't know if this is peculiar only to the SanDisk Wireless stick or if most of these wireless memory sticks can only be in one function (USB Mode or Wireless Access) at a time. Presumably this is to avoid corruption of data or read/writing conflicts or getting partial files. I get it. But it would have been nice to be able to gain access to the stick on-the-fly with it always plugged in receiving data, even to view partial progress (as it is all simple text-based files anyways).

author: S. Petrukhin
author_rank: Super Contributor
timestamp: November 23, 2020, 11:18:06 pm
content: A few years ago, I tried an SD card with a WiFi interface in my camera. I didn't like the transfer speed.

author: Zbig
author_rank: Frequent Contributor
timestamp: November 26, 2020, 05:38:58 pm
content: Quote from: edy on November 23, 2020, 05:23:15 pmIt's due to how regular (as in: non-network) filesystems work. Whether the stick is formatted in FAT32, NTFS or exFAT, you cannot guarantee a consistent filesystem view from multiple hosts (or multiple OSs) connected to one block device - at the block device level - at once. Imagine you work with the data on your computer's drive where something (rouge process, virus, etc.) is changing random sectors behind your (and you OSs) back. The only guarantee of filesystem consistency is when there is only one "entity" accessing and modifying the actual data and the metadata (be it FAT, MFT or other) in a strictly controlled and synchronised fashion.You could argue there's no problem as long as only one host has a read-write access to the media and other(s) only access it in read-only way and that would be true in a sense that no filesystem corruption on the actual media could occur but, even in this scenario, you could not guarantee the integrity of the in-flight data as seen by the read-only host whilst in the process of being modified by the R/W host (i.e. the data logger in your case).Then again, you could argue that "but there is SMB/CIFS, NFS, etc. where you could have many concurrent users both reading and writing the data". The problem is, the gizmo that is accessing the media (USB stickdatalogger) would have to be aware of that and have all the necessary server software stack implemented.To sum up: with all my disdain for Western Digital (a SanDisk brand owner) that's not laziness on their part but rather the fundamental limitation of how "classic" disk file systems work.That said, I'm actually in the process of developing a Raspberry Pi Zero-based product that uses the OTG functionality mentioned by David. Naturally, it won't overcome the limitation I was talking about but will attempt to mitigate it to a degree by implementing features like unmount-update-remount, shadowing the data to the staging area for later auto-sync, etc.