5.2 : PCIe Switch
The VP3500 utilizes PLX Technology’s PEX8648, a 48-lane, 12-port, generation 2 PCIe switch.
The switch is used to interface the system processor/s to the VP3500’s devices. The device is a high-
performance switch and supports features such as non-blocking switch architecture, low-power and
configurable port configuration. Please reference the PEX8648 specification for additional features and
information.
The PEX8648 port configuration is determined by strapping pins upon the release of reset. The device
may be reconfigured by the on-board microcontroller as well. For example, the default VPX port setting
is 4x4. That configuration may be changed to meet system requirements to a 1x16 or 2x8. Please see
section 5.3.
The below figure illustrates the default PCIe Switch configuration as implemented on the VP3500.
Port 0 (x1)
Mini PCIe 1
Mini PCIe 2
Port 1 (x1)
PCI Bridge 1
Port 2 (x4)
PCI Bridge 2
Port 3 (x4)
P
or
t 4
(x
4)
P
or
t 5
(x
4)
P
or
t 6
(x
4)
P
or
t 7
(x
4)
VPX
Port 8 (x8)
Port 9 (x8)
XMC 1
XMC 2
PEX8648
Figure 13 : VP3500 PCIe Switch Default Configuration
VP3500 User Manual • Document Number 101-3500-0001 • Revision A0
Property of Rigel Engineering, LLC. Confidential & Proprietary
690 Cone Park Court, Merritt Island, Florida 32952
page 84
