Hi, On Tue, Oct 28 at 12:39, Edward Beckmann wrote: > Thanks for the replies so far - one problem, the externals I am thinking of > have no power supply or separate switch - I need to turn off the power from > the USB port they are plugged into (and where they get their power from). I > am trying to avoid lots of plugging and unplugging the USB lead.
How happy are you with the C compiler ? I don't know of an off the shelf utility for this but I've had some success with the hub-ctl program from NIIBE Yutaka[1]. Actually compilation of the single source file is simple enough. $ cc -o hub-ctrl hub-ctrl.c -lusb Assuming you have libusb installed (on gentoo it's "emerge libusb"). Then it's simply "hub-ctrl -b 1 -d 2 -P 3 -p 0" to turn power off, and "hub-ctrl -b 1 -d 2 -P 3 -p 1" to turn it back on. In my example 1 is the bus the *hub* is attached to, and 2 is the device number of the *hub*, 3 is the port on the hub that you wish to control. Determining the port number is either a case of checking the hub circuit diagram or trial and error. Hub port numbers never follow a logical layout or the numbering on the case. ie and 8 port unit I know has the ports left to right in the following order 1 2 3 4 7 8 6 5. Add the hub-ctrl commands to a script that mounts/unmounts the drive as you require. [1] http://marc.info/?l=linux-usb-devel&m=113724451205634&w=2 -- Bob Dunlop -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --------------------------------------------------------------
