EXPANSION CHASSIS
6-4
PCIe2-2712 PCI Express Gen2 Expansion System User’s Manual
Revision 1.0, February 2015
6.3.6
J28, J29, J32 “THM1”, “THM2”, THM2X” Thermistor Connectors
Remotely placed thermistors attach here. The Monitor board circuitry can provide remote temperature
sensing for specific enclosure locations through thermistors attached at these connectors. The Monitor
board circuitry requires a 10Kohm NTC thermistor such as US Sensor p/n USP10982. There is no
polarity requirement. Note that location J32 “THM2X” is not enabled. It is an alternate location for
“THM2” on the opposite side of the PCIe2-462. Board components must be moved to enable
“THM2X” and disable “THM2”.
6.3.7
J35 “PLX I2C” PEX Device Editor Connector
Normally not installed. This connector allows access to the PLX PCIe switch on the PCIe2-462. PLX
supplied software and hardware is required.
6.3.8
J36 “ALTERA JTAG” JTAG Connector, J36 “XILINX JTAG” JTAG Connector, J19-J23
“JTAG”, JTAG Bypass Jumper for Slots J1-15, J14-J18 “JTAG”, JTAG Bypass Jumpers
for Slots J8-J12
Normally not installed. A JTAG chain is implemented on the PCIe2-462 from the JTAG connector thru
each PCIe slot back to the JTAG connector. Two JTAG connectors are provided, one to a Altera specifi-
cation (J36) and one to Xilinx specification (J37). The two JTAG connectors are wired in parallel and
using only one at a time is anticipated. The Xilinx connector is Molex 87831-1420 or equivalent. The
JTAG chain passes thru JTAG devices on installed boards at each slot. In the event a board is not
installed, the JTAG chain is broken. The JTAG bypass jumpers at each slot allow the JTAG chain to be
mended.
Table 6-4. J36 ALTERA JTAG Connector
Pin
Signal
1
TCK
2
GND
3
TDO
4
+3.3V
5
TMS
6
no connection
7
no connection
8
no connection
9
TDI
10
GND
