Installing and Replacing Desktop Board Components
49
USB 2.0 Headers
Figure 23, J shows the location of the USB 2.0 headers. Table 14 shows the pin
assignments and signal names for each USB 2.0 header. Each USB header can be
used to connect two USB devices.
Table 14. USB 2.0 Header Signal Names
USB Port A
USB Port B
Pin
Signal Name
Pin
Signal Name
1
Power (+5 V)
2
Power (+5 V)
3 D-
4 D-
5 D+
6 D+
7 Ground
8 Ground
9 Key
10
No
Connection
Note: USB ports may be assigned as needed.
NOTE
Computer systems that have an unshielded cable attached to a USB port might not
meet FCC Class B requirements, even if no device or a low-speed USB device is
attached to the cable. Use a shielded cable that meets the requirements for a
full-speed USB device.
Serial Port Header
See Figure 23, E for the location of the serial port header. Table 15 shows the pin
assignments for the header.
Table 15. Serial Port Header Signal Names
Pin Signal
Name
Pin Signal
Name
1
DCD
2
RXD#
3 TXD#
4 DTR
5 Ground
6 DSR
7 RTS
8 CTS
9 RI
10
No
Connection
