Chapter 3 Using Your Computer 35
Using Multiple USB Devices at the Same Time
You can purchase a USB hub to connect multiple USB devices to your computer. The
USB hub connects to an open USB port on your computer and provides additional USB
ports (usually four or seven). Hi-Speed hubs can support USB 2.0 Hi-Speed devices as
well as USB 1.1 compatible devices. USB 1.1 hubs don’t allow Hi-Speed USB devices to
operate at their maximum data speed. Some USB hubs have a power adapter and
should be plugged into an outlet.
Note: If you are using a chain of USB devices and hubs, some USB devices may not
work when connected through a combination of USB 2.0 Hi-Speed hubs and USB 1.1
full-speed or low-speed hubs. For example, you may not see an external USB hard disk
on your desktop. To avoid this problem, do not connect USB devices with different
speeds together. Connect your Hi-Speed hub directly to your computer and connect
Hi-Speed devices to it. Connect a full-speed or low-speed hub to your computer
directly and connect similar speed devices to it.
For More Information on USB
Additional information on USB is available in Mac OS Help. Choose Help > Mac Help in
the menu bar and search for “USB.” You can also find information on the Apple USB
website at www.apple.com/usb.
For information on USB devices available for your computer, check the Macintosh
Products Guide at www.apple.com/guide.