USB Emulator

[pinballdave]

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. ;)