Video - Lcd has a usb slot but it does not work

What is the power output of a USB port? usb a slot USB & 3 x USB Ports POR-1484 USB Hub You can buy different types of USB ports online that vary in size, parameters, speed, and the number of slots usb slot types LG Lcd has a usb slot but when I insert any device like pendrive with images or videos or connect didicam with it it does not work

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