PEX 8509RDK Hardware Reference Manual v1.1
© 2007, PLX Technology, Inc. All rights reserved.
3
2. PEX 8509RDK Hardware Architecture
Figure 2-1. PEX 8509RDK Hardware Architecture
2.1
PEX 8509 PCI Express Switch
The PEX 8509 is a 8-lane, 8-port (maximum) PCI Express switch, which can be configured using strap
pins or EEPROM. The RDK’s onboard PEX 8509 is set up as a 5-port switch, with one x4 upstream port
(Port 0) and four x1 downstream ports (Ports 1 - 4). Port 0 connects to the card edge (P1), while Ports 1,
2, 3, and 4 connect to x16-sized slot connectors (J1, J2, J3, and J4 respectively).
Port 0
PEX 8509
Port 4
Port 2
Port 1
x16 Connector
x4 Card Edge
Hot Plug
Power Ctl.
EEPROM
I2C
DIP
switch
x4
8
2
4
Reset
Timer
PERST#
REFCLK
JTAG
connector
5
x16 Connector
x16 Connector
P1
J3
J2
J1
Port 3
x16 Connector
J4
Ref
C
lk
Bu
ff
er
RefClk
Buffer
x1
x1
x1
x1
