TXMC885 User Manual Issue 1.0.0
Page 8 of 12
3
PCI Device Topology on TXMC885
The TXMC885 uses four Gigabit Ethernet Controllers (Intel 82574IT) each communicating via a PCIe
Rev. 1.1 compliant x1 Interface. To be able to access the Ethernet controllers they are connected to the x1
Downstream Ports of a PCIe Switch (IDT 89HPES8T5A). The x4 Upstream Port of the Switch is connected
to the XMC Connector communicating with the host system.
Figure 3-1 : PCI Device Topology
NOTE: Operating systems typically assign the lowest available Ethernet device number to
PORT4, thus initializing the four ports in descending order.
