Why USB 2.0 HUB cannot recognize the external devices?

First, please do not use the USB HUB to connecting some larger power demand devices like Portable Hard Disk、CD-ROM without power supply. In normal situation, a USB 2.0 HUB can connect 3 devices which power demand smaller USB devices (keyboard/mouse/USB drive/card reader etc.).
It may appear some situations like, read slow/cannot recognize devices/devices disconnected, due to the current limit of the USB 2.0 port and please connect the USB HUB external power cable. We will appreciate to answer your questions please contact vcomnet@vcom.hk.
Joy Wu
Richard Chan
Working Time:
9 am- 6 pm
VCOM Enquiries