
Interfaces and Connectors
EBX-18 Hardware Reference manual
33
USB
The USB interface on the EBX-18 is OHCI (Open Host Controller Interface) and EHCI
(Enhanced Host Controller Interface) compatible, which provides a common industry
software/hardware interface. The board has five USB ports:
Three on-board ports at locations J20, J21, and J22 using standard USB Series A sockets
(see Figure 5 on page 12)
Two hubbed ports routed to the J10 I/O connector. Table 11 page 25 lists the USB port
signals routed to the J10 connector.
The USB interfaces at connector J10 are accessible using a CBR-4004B paddleboard or by using
a custom cable. Figure 23 on page 54 shows the connection points for accessing the USB ports
routed from J10 to a CBR-4004B paddleboard.
All five USB ports use IEC 61000-4-2-rated TVS components to help protect against ESD
damage.
BIOS
C
ONFIGURATION
The USB controller can be enabled or disabled in the BIOS Setup program.
microSD Socket
The EBX-18 includes a microSD socket. The VL-F41 series of microSD cards provide solid-
state storage of 2 GB, 4 GB, or 8 GB. The microSD socket accommodates cards with up to 32
GB of storage capacity. No drivers are needed, as the device interface is abstracted as a standard
parallel IDE drive on the master IDE channel. Note the following when using a microSD card
with the EBX-18:
The microSD card interface is not hot-pluggable. A microSD card will not be recognized as
part of the system if it is not plugged in before power is applied to the board or before a
push-button reset is applied. This is not a limitation of the EBX-18 board; it is a limitation
of the DX2 chip.
When a microSD card is inserted at power-up, the default boot setting is to boot from it (it is
primary), so if you don’t press <F11> right after applying power to the board, you will not be
able to select an alternate boot option; the board will “stall” for the lack of an operating
system (OS) if there isn’t one present on the microSD card.
The boot order can be changed in the BIOS Setup program.
If you remove the microSD card at any time and allow the board to boot without the card
installed, the boot order setting will be cleared and you will have to set it up again the next
time you use a microSD card.
If you remove the microSD card while the board is powered on and the OS attempts to access
a file on the “drive” (that is, the microSD card) the results are unpredictable. The best case
scenario is that the drive drops out (as it would in Windows Explorer when running
Windows 7 from a SATA drive and using the microSD as an additional hard drive).
However, if Windows does not try to access the microSD card while you have it out and you
put it back in (again, in Windows 7 at least) the system does not appear to have noticed it
was ever removed.