
One Stop Systems, Inc. OSS-KIT-EXP-4500
Rev. A
Page 8
4.c. Pin Assignments
Connectors PCIe x4 Card Edge Connector
•
The pins are numbered as shown with side A on the top of the centerline on the solder side of the board and side B on the
bottom of the centerline on the component side of the board.
•
The PCIe interface pins PETpx, PETnx, PERpx, and PERnx are named with the following convention: “PE” stands for PCIe
high speed, “T” for Transmitter, “R” for Receiver, “p” for positive (+), and “n” for negative (-).
•
Note that adjacent differential pairs are separated by two ground pins to manage the connector crosstalk.
Table 1: Pin-out for the PCIe x4 Card Edge Connector on the Host Cable Adapter
Side B
Side A
Pin #
Name Description
Name Description
1
N/C
N/C
PRSNT1#
Hot-Plug presence detect
2 N/C
N/C
N/C
N/C
3 N/C
N/C
N/C
N/C
4 GND
Ground
GND
Ground
5 NC
N/C
N/C
Not
connected
6
N/C
N/C
JTAG3
Host Mode:TDI (Test Data Input)
Target Mode: Test Clock+
7 GND
Ground
JTAG4
Host
Mode: TDO (Test Data Output)
Target Mode: Test Clock-
8
+3.3V
3.3 V power
N/C
Not connected
9
N/C
Host Mode: Not connected
Target Mode: Test Power On
N/C Not
connected
10
3.3Vaux
3.3 V auxiliary power
+3.3V
3.3 V power
11
N/C
N/C
PERST#
Fundamental reset
Mechanical key
12 RSVD
Reserved
GND
Ground
13
GND
Ground
14 PETp0
REFCLK
Reference clock (differential pair)
15 PETn0
Transmitter differential pair,
Lane 0
GND Ground
16 GND
Ground
PERp0
17
PRSNT2#
Hot-Plug presence detect
PERn0
Receiver differential pair, Lane 0
18 GND
Ground
GND
Ground
19 PETp1
RSVD
Reserved
20 PETn1
Transmitter differential pair,
Lane 1
GND Ground
21 GND
Ground
PERp1
22 GND
Ground
PERn1
Receiver differential pair, Lane 1
23 PETp2
GND
Ground
24 PETn2
Transmitter differential pair,
Lane 2
GND Ground
25 GND
Ground
PERp2
26 GND
Ground
PERn2
Receiver differential pair, Lane 2
27 PETp3
GND
Ground
28 PETn3
Transmitter differential pair,
Lane 3
GND Ground
29 GND
Ground
PERp3
30 RSVD
Reserved
PERn3
Receiver differential pair, Lane 3
31
PRSNT2#
Hot-Plug presence detect
GND
Ground
32 GND
Ground
RSVD
Reserved