USB mass storage hack?

[gareth2]

Posted on February 02, 2012 at 21:19

USB mass storage hack?

#usb-mass-storage

[Tesla DeLorean]

Posted on February 03, 2012 at 13:54

Forum ate your post, please try again.

[gareth2]

Posted on February 03, 2012 at 14:45

Hi Clive/all,

Im not too sure what happened to my original post but the question I was wanting to ask is: Can/has anyone hacked the USB Mass storage class to support data input/output from the STM32 to a PC. The idea is the STM32 would have a file structure with 2 files, input and output. It would update the output file as and when data was available and the input file would be updated from the PC. Through this two way comms could be held. How would windows see this? is it even possible? Any comments welcome and i know this is not a ''correct'' way of doing things. 😉

[Tesla DeLorean]

Posted on February 03, 2012 at 15:41

Well you could certainly doing it by faking a file system. I would hazard that doing it as a CDFS would be less traumatic than as FAT.

Personally, I think the easiest way would be to add a couple of non-standard SCSI commands that would allow two way communication. This is kind of how the STM32 VL-Discovery's ST-LINK works. It looks like a small capacity flash drive, with out-of-band communication to do the JTAG/SWD stuff. The Windows side application opens a channel to the drive letter, and then injects commands into the IO stack.

[jlchoobs]

Posted on April 18, 2012 at 19:19

Hey Devine,

Any luck with your question ? Do you have any code to demo this ? I am working on a related question of getting the Usb Mass Storage to work on the Stm32f4Discovery - with no results yet. I am trying to port the Stm3240G Board Code over. I can get the PC to see the Usb as Mass Storage  - but it then reports a 'can not start device' error. Take a look at my posts. Project :

http://stm32geeks.freewebspace.com/projects.html