USB Emulator

[cropwell]

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'.