Technical Reference
51
2.2.2.6
Front Panel USB Headers
Figure 12 is a connection diagram for the front panel USB headers.
NOTE
•
The +5 V DC power on the USB headers is fused.
•
Use only a front panel USB connector that conforms to the USB 2.0 specification for
high-speed USB devices.
Figure 12. Connection Diagram for Front Panel USB Headers
2.2.2.7
Low Pin Count (LPC) Debug Header
During the POST, the BIOS generates diagnostic progress codes (POST codes) to I/O
port 80h. If the POST fails, execution stops and the last POST code generated is left at
port 80h. This code is useful for determining the point where an error occurred (refer
to Section 4.5 on page 69 for a description of the POST codes).
Displaying the POST codes requires a POST card that can interface with the Low Pin
Count (LPC) Debug header. The POST card can decode the port and display the
contents on a medium such as a seven-segment display.
Table 26. LPC Debug Header
Pin
Signal Name
Pin
Signal Name
1
CK_33M_DEBUG
2
GND
3
PLTRST#
4
LFRAME#
5
LAD0
6
LAD1
7
LAD2
8
LAD3
9
GND
10
GND
11
+3.3 V
12
+3.3 V
13
Not connected
14
+3.3 V
