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Alvium USB Cameras User Guide V3.6.4
Performance and troubleshooting
Linux: Activating U3 mode
1. Connect to the camera and use as you like.
2. Set
DevicePowerSavingMode
to
SuspendMode
.
3. Close all
Vimba
Connections, including the first
Vimba Viewer
dialog.
Linux requires to change the following settings to bring a USB device to U3 mode:
• power/control => auto
• power/autosuspend_delay_ms => 0
The following script to put the camera to U3 mode can be used on most hosts.
4. Execute this script with root privileges. For example, save this script as
U3.sh
and use the command
sudo ./U3.sh
:
#!/usr/bin/env bash
# https://www.kernel.org/doc/html/v4.13/driver-api/usb/power-
management.html#the-user-interface-for-dynamic-pm
find -L /sys/bus/usb/devices/ -maxdepth 2 -regextype posix-
extended -regex '/sys/bus/usb/devices/[0-9]+\-[0-9]+' | while
read port; do
if [[ $(< $port/idVendor) == "1ab2" ]]; then
if [[ $1 == on ]]; then
echo "Activating port: $port"
echo on > $port/power/control
echo 2000 > $port/power/autosuspend_delay_ms
else
echo "Suspending port: $port"
echo auto > $port/power/control
echo 0 > $port/power/autosuspend_delay_ms
fi
fi
done
Code Listing 1: Linux script to change to U3 mode
