PCI Express moves into the real world as more companies such as NEC Electronics deliver real products like the x8 PCI-X Bridge and Switch. These chips are based on NEC's 0.15-µm process technology. The cores are also available in custom chips. The PCI-X Bridge is one x8 upstream port that services two 133-MHz PCI-X bus segments. They also support the 64-MHz PCI mode. The Switch has two x8 upstream ports and four x4 downstream ports. The dual upstream ports can provide redundant connections, or the system can be partitioned into two sections using a proprietary, in-band configuration protocol.
There's no formal specification of PCI Express partitioning, so most PCI Express switch vendors are implementing their own configuration system. All ports comply with the 1.0a specification and include support for x1, x2, and x4 connections.
Pricing for the PCI-X Bridge starts at $38, while the x8 Switch goes for $90. Production quantities are scheduled for the second quarter of 2004.
www.necel.com