Every IQRF IDE instance communicates with one USB device only. The list of available USB devices is displayed in IQRF Device Manager window.
IQRF IDE has two modes to select a USB device. This selection can be switched in IQRF Device manager window or by a click to the icon on the bottom status bar which indicates the current mode. After IQRF IDE invoking the last used mode in last closed IQRF IDE instance is selected (except for invoking via a shortcut with a specific USB device, see IQRF Device Manager).
•Automatic USB device selection 
oOnly one USB device is connected to a PC
IQRF IDE communicates with the device connected. After disconnection of this device it will be assigned to any newly connected device.
oMore USB devices is connected to a PC
IQRF IDE communicates with the device which was connected first, or it is manually selected from the IQRF Device Manager window. IQRF IDE registers this device also after its disconnecting (displayed in grey in IQRF Device Manager window). Then IQRF IDE reports the message USB device not connected and checks whether the device is reconnected. This "remembering" can be refused by the Release USB Device feature or it is cancelled automatically after disconnecting of all USB devices from the PC. Then IQRF IDE will be assigned with the first USB device connected.
•Lock with specified USB device 
IQRF IDE communicates exclusively with a single particular USB device. After its disconnecting the IQRF IDE waits just for this given device and ignores any other devices. Also when launched the IQRF IDE waits for this given device. When multiple instances used the state of the last closed IQRF IDE instance is saved.
IQRF IDE can be invoked in this mode also by a shortcut created in the IQRF Device Manager window.