Altera Stratix IV GX FPGA Development Board - Manual (Page 40)

2–32 Chapter 2: Board Components
Components and Interfaces
Stratix IV GX FPGA Development Board, 530 Edition Reference Manual November 2010 Altera Corporation
Figure 2–9 shows the PCI Express reference clock levels.
The JTAG and SMB are optional signals in the PCI Express specification. Both types of
signals are wired to the Stratix IV GX device but are not required for normal
operation. The PCI Express control DIP switch allows the presence detect grounding
to be altered to enable a ×1, ×4, or ×8 width edge connector. The PCI Express control
DIP switch does not support auto-negotiation.
Table 2–34 summarizes the PCI
Express pin assignments. The signal names and directions are relative to the Stratix IV
GX FPGA.
Figure 2–9. PCI Express Reference Clock Levels
V MAX = 1.15 V
V CROSS MAX = 550 mV
V CROSS MIN = 250 mV
V MIN = –0.30 V
REFCLK –
REFCLK +
Table 2–34. PCI Express Pin Assignments, Schematic Signal Names, and Functions (Part 1 of 2)
Board Reference Description Schematic Signal
Name
I/O Standard
Stratix IV GX
Device
Pin Number
J17.A47 Add-in card transmit bus PCIE_TX_P7
1.4-V PCML
P36
J17.A48 Add-in card transmit bus PCIE_TX_N7 P37
J17.A43 Add-in card transmit bus PCIE_TX_P6 T36
J17.A44 Add-in card transmit bus PCIE_TX_N6 T37
J17.A39 Add-in card transmit bus PCIE_TX_P5 AB36
J17.A40 Add-in card transmit bus PCIE_TX_N5 AB37
J17.A35 Add-in card transmit bus PCIE_TX_P4 AD36
J17.A36 Add-in card transmit bus PCIE_TX_N4 AD37
J17.A29 Add-in card transmit bus PCIE_TX_P3 AF36
J17.A30 Add-in card transmit bus PCIE_TX_N3 AF37
J17.A25 Add-in card transmit bus PCIE_TX_P2 AH36
J17.A26 Add-in card transmit bus PCIE_TX_N2 AH37
J17.A21 Add-in card transmit bus PCIE_TX_P1 AP36
J17.A22 Add-in card transmit bus PCIE_TX_N1 AP37
J17.A16 Add-in card transmit bus PCIE_TX_P0 AT36
J17.A17 Add-in card transmit bus PCIE_TX_N0 AT37
J17.B45 Add-in card receive bus PCIE_RX_P7 R38
J17.B46 Add-in card receive bus PCIE_RX_N7 R39
J17.B41 Add-in card receive bus PCIE_RX_P6 U38
J17.B42 Add-in card receive bus PCIE_RX_N6 U39
J17.B37 Add-in card receive bus PCIE_RX_P5 AC38