InfoWhat is Permanent Device Assignment And What Limitations Does It Have?
You can set permanent assignment for certain USB device. It means, that every time this device is connected to USB port on your computer,
it will be automatically captured by either Mac or one of virtual machines according to preferences specified.
The assignments could be managed in the Permanent assignments list
Parallels Desktop -> Preferences -> USB
To add a new assignment:
1 Click the Add button below the Permanent assignments list.
2 Click the device field in the USB Device column to choose a USB device from the list.
3 In the Connect To column, double-click the destination field to open the list of available destinations and choose the virtual machine you want to connect this device to. If you want to connect this USB device to Mac OS X, choose Computer.
NOTE: To be able to use the USB device in the virtual machine, you may need to install the necessary drivers in the guest OS.
By default, such drivers can be obtained from the device manufacturer site.
4 Click OK to apply the changes.
NOTE: You can connect up to eight USB 2.0 devices and up to two USB 1.0 devices to each virtual machine.
If you have several virtual machines (VMs) and set a permanent device assignment to VM #1, but have the only VM #2 started, the system will ask you where to connect this device to (to VM #2 or to Mac). If two machines are running and a device was already connected to one of them, the second one would not be able to see this device and operate with it unless it is unmounted from the VM # 1. So, even though you have permanent device assignment to VM #1, this USB will not work with VM #1 before it it disconnected from VM #2.
More details about USB device mapping mechanism could be found in Knowledgebase article https://kb.parallels.com/en/5684