Product Description
Dual-Core Intel® Xeon® Processor LV and Intel
®
3100 Chipset
User’s Manual
January 2007
18
Order Number:315879-002
1.4.2.7
USB
The CRB has a 10-pin, dual-row header to route two USB Ports to an external USB
connector.
• Allows two USB 1.1 or 2.0 ports to be routed to the dual-stack rear I/O or
optionally to the 10-pin header from the internal I/O. These USB ports are Port 2
and Port 3. Rear panel ports 2 and 3 are not simultaneously functional.
• By default, routing for USB is to the dual-stack header on the rear panel I/O.
• In conjunction with the rear panel USB Ports there are only a total of four USB
ports.
More information is available in
Section 1.4.4.3, “USB Ports” on page 19
.
1.4.3
I/O Slots for Expansion Capabilities
1.4.3.1
PCI Express*
The CRB provides a total of 3 x4 PCI Express* ports.
• Port A provides two x4 connections through two x8 connectors
• Port B provides one x4 connection through one x8 connector
• 32-bit ECRC (Port A only) stays with packet ensuring correct data at destination
• 256 opportunistic combining for read completions to improve performance
• ONLY Port A provides posted writes between each x4 port
• ONLY Port A provides memory-to-I/O DMA
Note:
The PCI Express* Ports are x8 connectors, but ONLY have the functionality of a x4
connector. This enables you to use a x8 card on the CRB but it has the bandwidth and
functionality of the x4.
Warning:
Hot-Plug is NOT supported on this platform.
1.4.3.2
PCI
The CRB provides one PCI slot. It has the following characteristics:
• Specification 2.2 compliant
• 32-bit
• 33 MHz
• 120 MB/s throughput
• 64-bit addressing through the DAC protocol
