On Wed, Jun 3, 2009 at 3:23 PM, Mark Rages wrote: > On Tue, Jun 2, 2009 at 11:11 PM, Youda He wro= te: >> Read through the discussion, still does not have a solution. >> >> Here a more detailed problem description: >> >> We need to remotely capture image using digital cameras, and then downlo= ad >> the images to computer. >> So far we have tried the following: >> >> 1: Camera set to external USB mode, using a relay to cut off the 5V line, >> works, but not reliable, once in a while, kills a camera. =A0Advantage o= f this >> method is download speed is good. >> >> 2: Camera set to remote camera using WIA (Nikon DSLR has these), we don't >> need to cut off the USB, the problem is the downloading speed is very sl= ow, >> and if user happens to view image in the camera folder, the camera captu= re >> is very hard to get synchronized, since the camera is acting as a "serve= r", >> busy working on too many things. >> >> We are currently using the tethered method, communicate with camera using >> windows WIA method, solved killing camera issue, but created synchrizati= on >> and download speed issue. >> >> We want to try the USB downloading method again, since we have too many >> images and speed is important now again. >> >> -- Youda >> > > I don't know how to issue a USB suspend in Windows. In Linux, you would do > > echo "suspend" > /sys/bus/usb/devices/2-6/power/level > > where 2-6 is the kernel's enumeration of the USB device you are trying > to suspend. =A0(You can track it down by looping through the entries in > /sys/bus/usb/devices/*/id{Manufacturer,Product} or by cooking up a > udev rule, or by parsing the output of lsusb / udevinfo.) > I forgot so cite my sources, sorry. Linux USB power API description: http://lxr.linux.no/linux+v2.6.29/Documentation/usb/power-management.txt see also this article: http://www.lesswatts.org/projects/devices-power-management/usb.php and browse source: http://lxr.linux.no/linux+v2.6.29/drivers/usb/core/sysfs.c#L370 -- = Mark Rages, Engineer Midwest Telecine LLC markrages@midwesttelecine.com -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist