SX2-express SinglePRI ISDN board configuration (kb3872)

The information in this article applies to:

  • SX2-express SinglePRI

[ Summary | Information ]


The ISDN board SX2 SX2-express SinglePRI needs to be configured before first use. This article gives an overview about the possible configurations.


Before the SX2-express SinglePRI card is inserted in the machine you have to configure the RJ-45 socket pinout and the line termination.

The following description assumes you have the card in front of you with the RJ-45 sockets on the left side and the PCI-express connector pointing in your direction. Each RJ-45 socket has two jumper blocks assigned. Throughout this description the jumper block containing 2 jumpers is named JB2 and that one containing 5 jumpers is named JB5. A suffix L,R.U or D means that either all jumpers are on the block's left side (L), the right side (R), the upper side (U) or the down side (D), e.g. JB5L means that all jumpers of JB5 are jumpered to the left side.

RJ-45 Socket Pinout

SX2-express SinglePRI interface configuration
SX2-express SinglePRI interface configuration
Click to enlarge...

The RJ-45 socket pinout can be changed with jumper blocks JB2 and JB5. It is possible to chose out of 4 different pinouts:

Jumper Block Assignment RJ-45 Socket Pinout
JB2L and JB5R

Pin1 = TX+

Pin2 = TX-

Pin4 = RX+

Pin5 = RX-

JB2R and JB5R

Pin3 = TX+

Pin6 = TX-

Pin4 = RX+

Pin5 = RX-

JB2L and JB5L

Pin1 = RX+

Pin2 = RX-

Pin4 = TX+

Pin5 = TX-

JB2R and JB5L

Pin3 = RX+

Pin6 = RX-

Pin4 = TX+

Pin5 = TX-

Board number configuration

SX2-express SinglePRI board number
SX2-express SinglePRI board number
Click to enlarge...

The board number can be set with the six DIP switches located at the upper middle side of the board. The following assignment is valid:

Switch 4 Switch 3 Switch 2 Switch 1 board number
off off off on 1
off off on off 2
off off on on 3
off on off off 4
off on off on 5
off on on off 6
off on on on 7
on off off off 8
on off off on 9
on off on off 10
on off on on 11
on on off off 12
on on off on 13
on on on off 14
on on on on 15
off off off off automatic

Please note that you have to use the numering shown in the picture rather than the numbering on the DIP-switch itself.

Please make sure that you either assign a board number for all boards in the system or configure all boards for automatic number assignment.


PCM bus connection

SX2-express SinglePRI PCM connector
SX2-express SinglePRI PCM connector
Click to enlarge...

The board provides two connectors with 20 pins each. Those connectors are used to connect two boards with an optional PCM cable. The upper connector is the output and the lower connector is the input. Connect two boards with a PCM cable by connecting the output of the first board with the input of the second board.

LED Status Monitoring

Each E1 socket has assigned 4 monochrome LEDs as a status monitoring facility.

The following assignment is valid:

LED1 off: Layer 1 de-activated
LED1 red: Layer 1 activated
LED2 green: Layer 2 activated
LED3 green blinking: At least one connection active
LED4 red blinking: The line is being configured


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