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EBX-38 Hardware Reference Manual
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Multi-purpose I/O
USB Interfaces
The EBX-38 offers a total of 1 on-board USB 3.0 port, 4 off-board (paddleboard) USB 2.0 ports,
and 4 on-board USB ports (2 to the Type A connectors and two for the Mini Cards). An
additional USB 2.0 port is paired with the USB 3.0 port. This configuration requires two USB
hubs; one USB2513B and one USB2514B as shown in the EBX-38 Block Diagram. The figure
below shows the location of the USB ports on the baseboard.
This interface can operate using either the Atom processor’s EHCI controller or its xHCI
controller. To use the USB 3.0 Super Speed mode, the xHCI controller must be used. USB
controller selection is set in the BIOS. By default, EHCI is used. Some older operating systems
(such as MS-DOS) may not support xHCI.
Figure 13. Location of the USB Ports
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