Publication No. SBC329-HRM/1
Connectors 115
7.2.3
Signal Descriptions
Table 7-11 XMC Signal Descriptions
Signal
Description
PCIE_TX[7:0]P/N
PCIe Transmit Differential Pairs (from XMC to SBC329)
PCIE_RX[7:0]P/N
PCIe Receive Differential Pairs (from SBC329 to XMC)
REFCLK_P/N
PCIe Reference Clock. 100 MHz differential clock to XMC
GND
Signal Ground
P3V3
+3.3 V supply pins
VPWR
Main power input rail. Supplied via direct connection to VS3 (+5V)
RESET_IN~
XMC Reset In. Reset driven from the SBC329 to the XMC
RESET_OUT~
XMC Reset Out. Reset signal driven by the XMC to the SBC329 (from a front-panel switch for example)
P12V_AUX
+12 V auxiliary supply pins
N12V_AUX
-12 V auxiliary supply pins
GA[2:0]
Geographic Address. Used to identify the address of the XMC on a shared I
2
C bus (GA of 000
b
for XMC site)
MBIST~
XMC Built-in Self-Test. This signal can be held low by the XMC to indicate that it is not yet ready to be enumerated by
the root complex
PRESENT~
XMC Present. Pulled low by the XMC to allow the SBC329 to detect if an XMC is fitted
P3V3_AUX
+3.3 V auxiliary supply pins
SM_DATA, SM_CLK
Data and Clock lines for a two-wire I
2
C system management bus. Connected to the BMM
NVMRO
Non-Volatile Memory Read Only. Used to write protect any non-volatile memory on the XMC. Connected directly to the
VPX backplane signal NVMRO
XMC_xxx
Rear I/O connection from XMC site
N/C
No connection
7.3 P5 Connector (TAC)
This 80-way Molex connector (where fitted) is for Abaco/Field Application Engineer
use only. It provides an interface between the TAC and on-board programmable
devices.