[f5soh]

Added a wiki page for board recovery using DFU.
Updated windows dfu_script for Revolution, RevoNano and Sparky boards.

https://librepilot.atlassian.net/wiki/display/LPDOC/Recover+board+using+DFU

[estauss]

I've had much trouble with this. I tried to flash Raceflight but something was corrupt during the process. revo would no longer connect via usb and would only show solid green led, SBL pads not shorted. I tried dfu_util method with no success. i have now tried method detailed herehttp://www.southquay3d.com/index.php?route=news/article&news_id=9 and flashed ef_revolution.bin successfully.
I still have no usb activity on PC but leds are active. solid green and pulsing long blue and short orange.
stm32 Bootloader not visible in Zadig either... running out of ideas.

[Brian]

You re-flashed the firmware via SBL on a UART, right?  I suspect your USB is bad.  The easiest way to test this is to short the SBL pad and plug the board into your PC.  You should get an STM32 DFU device added.  If you don't get that, then your USB is probably bad on the board.  You can watch for the device being added either in the device manager in Windows or using dmesg on Linux.  Even if you don't have the right drivers on windows it should add some USB device and will call it unknown.

[hwh]

Have you tried a different USB cable and different USB port on the computer?  Bad USB cables are way more common than most people think.