emulate a USB mass storage device

[DanielT]

Ok weird one for you,

I have a device that records video input and then will 'send' it to a pendrive (fat32), it just moves the video/still image file from it's buffer to the pendrive when you hit a button. Then you take the pen drive out walk across the room and pop it in a pc, and then load up the video/image.... problem is this all happens in a environment where you don't terribly want to be hands on with things you don't have to, i.e. a sterile environment, oh and it wastes time which you really don't have.

So my question is; can you get a PC to emulate a USB storage device?

This is what i want: I connect a usb cable to the device and the other end of usb cable to a linux/windows/mac (anything really we have them all) and when i hit 'send' on the machine, instead of it writing that info to the pendrive it blasts it over to the pc (where i can create script to watch the directory and automatically display the images etc etc).

Any other solutions to this problem are of course welcome. I might be missing an obvious one.

Thank you.

[breakpoint]

Well basically you need the PC to somehow set the USB host port into slavemode this is far beyond my knowledge as to how. Then there is the fake im a USB drive thing to think about.

Best place to ask this one is the Linux Kernel Mailing List.

[R.Smith]

Just out of curiosity: why a USB link and not ethernet? USB's not nearly as fast as good ol' CAT5.

[mrben]

Just out of curiosity: why a USB link and not ethernet? USB's not nearly as fast as good ol' CAT5.

Did you read the original post?

I have a device that records video input and then will 'send' it to a pendrive (fat32), it just moves the video/still image file from it's buffer to the pendrive when you hit a button.

I suspect that said device _only_ has a USB connection

[mrben]

I asked on IRC, and somebody (astinus) said the LTSP do something like that - might want to try contacting them.

[DanielT]

I suspect that said device _only_ has a USB connection

This is true.

I asked on IRC, and somebody (astinus) said the LTSP do something like that - might want to try contacting them.

Thanks, i'll have a poke around LTSP see what they have to offer.

I'll post back if i find a solution.

[R.Smith]

Did you read the original post?

Yes, although it wasn't clear to me that the device only had a USB port. :p

[Mig21]

A while ago I was looking for a way to make a PC emulate a USB HID, but that can't be done. Or rather - it can be done if you're willing to spend a year or two writing a driver for the 'device' pc.

I suspect it's the same thing with mass storage. It may be that someone has done it already (LTSP sounds like a good candidate), otherwise you're out of luck.

[Parau]

Any news about a solution to this problem? I'm interested in something similar. Thank you!

[Elleomea]

If you can switch in to USB device mode (which I doubt is possible with a PC) then you can use the usb gadget API, there's already a driver implemented for doing this sort of thing, you'd simply need to run:

modprobe g_file_storage file=/dev/sda1 (replacing sda1 with the drive you want)

However you must unmount any device you're making available via this method, if it gets written to by anything other than the g_file_storage driver you could face some serious corruption problems (you could use a file instead of an actual block device to avoid this sort of nastyness).

[Prometheus]

Hey only came here 'cos of the spam. Its a late suggestion but did you think of usb-over-ip ?
http://www.usb-server.com/ (hates freedom)