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I have an USB device based on FTDI chip. Sometimes, its driver get stuck.

Under linux, there no problem -- device get automatically disconnected, and reconnected by default kernel, and only problem is device name changed -- that can be fixed by udev rules.

Under windows, when it stuck, application's thread that does read() or write() at that moment are completely hangs. It can't be killed nor by TerminateThread, nor by KillProcess.

The only way to kill app -- is disconnect USB device physically.

Any way to issue programmatically device reconnection, that will remove driver's deadlock and allow to re-open port and continue working after?

Administrative rights application can have, if that required.

Mike Mackintosh
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datacompboy
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  • "devcon.exe restart * ftdi *" "devcon.exe disable * ftdi *" are fails while in hung state – datacompboy Dec 22 '12 at 08:50
  • The bad news is that the FTDI-based devices are the most reliable ones on the market! - devices based on the PL2303 (and/or their chipset vendor's drivers) are severely broken. – marko Dec 23 '12 at 01:29
  • Did you try a newer driver from [ftdichip.com](http://ftdichip.com)? – Turbo J Dec 23 '12 at 19:27
  • Always using latest driver. And tried to contact with support of ftdi without luck. Currently, only alarming of user to "please reconnect device" possible, trying to find another solutions. – datacompboy Jan 03 '13 at 16:43
  • http://stackoverflow.com/questions/916296/how-can-i-cycle-a-usb-device-from-c/919836#919836 – theli Jan 09 '13 at 12:21
  • devcon didn't work, so emulation of it didn't work either – datacompboy Jan 09 '13 at 17:43

1 Answers1

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I would suggest that you move your thinking up a step. You are trying to restart the USB device directly, why not try the hub?

I had a similar problem, and doing:

devcon remove *ROOT_HUB* && devcon rescan

Re-attached the USB device to the hub when it was hung.

Note: This will remove ALL USB devices from the device manager and re-add them. You can use expect or alike to do devcon findall *ROOT_HUB* and remove either ROOT_HUB20 or ROOT_HUB30 as needed.

Mike Mackintosh
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