FAQ TWedge
USB Device Loses Connection When Not Used for a While
USB Device Loses Connection When Not Used for a While
Problem: My USB Device (Virtual COM Port) loses connection when not used for a while.
Power management is a common cause of USB-connected device issues. To save power, Windows automatically shuts down the power to USB ports. This may cause problems with auxiliary devices and leads to a connection loss if you don't use the device for a while.
Workaround: Here are some measures, which you can try step by step until the problem disappears:
a) Prevent Windows from Turning Off USB Devices
- Open Device Manager by typing device manager in the Start 🡒 Search panel.
- In the Device Manager expand the Universal Serial Bus controllers branch, double-click the USB Root Hub device and choose the Power Management tab.
- Turn off "Allow the computer to turn off this device to save power" by unchecking the box.
- Click the OK button
b) Motherboard: If your BIOS has a setting 'Deep Sleep Control', then disable it.
c) Turn off the "hybrid sleep option" (if available):
- In Control Panel go to Power Options 🡒 Change plan settings 🡒 Change advanced power settings 🡒 Sleep 🡒 "Allow hybrid sleep" and turn it OFF.
d) Turn off "USB selective suspend" (if available):
- In Control Panel go to Power options -> Change plan settings 🡒 Change advanced power settings 🡒 USB settings 🡒 "Selective suspend" and disable it.
Especially for virtual COM ports TWedge offers a monitoring option to detect connection losses and automatically reconnect to the device (see TWedge interface options). You can also try these monitoring options.