You'd think all the 3D printing Gurus would be shouting about wireless SD cards that you can transfer files to, I'd buy one for my printer!
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You'd think all the 3D printing Gurus would be shouting about wireless SD cards that you can transfer files to, I'd buy one for my printer!
Looks like with the right version of FlashAir you can, but it's not an intended or supported function :D
https://mattshub.com/2017/04/11/flashair-sd-card/
Not sure if the WiFi stick will do the job. It seems more to WiFi whatevers been loaded onto the stick.
Then I had a thought;
All I need is a 4 way 2 pole switch to connect my USB stick to either the PC or the controller!
Cannabalise 2 USB leads, get a box for the switch and a panel mount USB socket and away you go, just keep lead length to the switch box less than 5 metres for reliability, so you have up to 10 metres of separation and you only have to walk a max of 5 metres to the switch.
There's a good reason why WiFi SD cards (or USB sticks) are generally read only from the wireless connection. If you were to make a change to a file on the SD card via the wireless connection, there is no way of telling the host system it's physically plugged into that the file system has been changed.
So if you try to read a new/changed file, the host system may have cached the old directory structure/file and not be able to see the changes. Or worse, the host computer wants to write some data and overwrites the blocks containing your new file which then corrupts the file system.
File systems that can be modified by two separate clients are quite complicated, and require both clients to know that the file system is volatile (something that SD cards and USB mass storage do not support). So given that 99% of the potential users won't have a clue about how the underlying technology works and simply want something that 'just works' you can see why manufacturers are reluctant to enable this behavior (or won't support it if it is possible), as it would be a nightmare to have to keep explaining it to the non technical users.
From the article about the Toshiba cards, it looks like there is an option on the 3D printer specifically for this. This is likely to make the 3D printer aware that the contents of the card might have changed since it last read something from it. Your controller is unlikely to have this kind of option.
However, if your controller never writes to the USB storage, then you might get away with it if you simply unplug and replug the storage after it's been modified via WiFi.
At this point a clunky switch box sounds even more attractive. ;)
Fortunately the 3D printer only reads files from the root directory of the SD card, so provided that you do not alter the file structure whilst the print is active, I anticipate that there should be no problem. I have yet to receive my Flashair card and reconfigure it to operate in STA mode. This is a side issue from the OP's USB problem and as I am not familiar with the DDSV controller, I have hesitated to offer any solution other than to agree with the OP when he suggested a two way switch. If I had a DDSV, I would probably take on the problem of using a WiFi USB stick, that sort of project intrigues me, but I ain't got one, so I won't. The best guy to give an opinion on the DDSV is probably MadModder.
I suspect that the DDSV will be a simplistic read of the USB when running the Gcode, much the same as the 3D printer, using the stick as a memory extension. The stick would only be read when running a job and I would not think it likely or desirable to mess with the files while chewing metal or wood.
My own CNC machine runs Mach3 from files on my personal cloud and the CNC computer has the Internet gateway disabled, so I have the benefit of LAN access to everything without Microsoft deciding that an update is more important. I apply the principle that, once the job is running, leave the files alone until it finishes.
Having spent 33 years in IT, I am surprised and delighted when something 'just works'.
My 3D Printer (Marlin based) can and does read from sub-directories.