Chapter 2 Configuration and Installation
© National Instruments Corporation 2-3 SCXI-1121 User Manual
– Jumpers W3, W19, W29, and W41 configure the first-stage gain
of input channels 0 through 3, respectively.
– Jumpers W4, W20, W30, and W42 configure the second-stage
gain of input channels 0 through 3, respectively.
– Jumpers W5, W21, W31, and W43 configure the first-stage
filtering of input channels 0 through 3, respectively.
– Jumpers W6 and W7, W8 and W9, W10 and W11, and W12 and
W13 configure the second-stage filtering of input channels 0
through 3, respectively.
– Jumpers W14 and W15, W22 and W23, W34 and W35, and W46
and W47 configure the voltage or current mode of operation for
excitation channels 0 through 3, respectively.
– Jumpers W16 and W26, W24 and W25, W36 and W37, and W48
and W49 configure the level of excitation for excitation channels
0 through 3, respectively.
– Jumpers W1 and W2, W17 and W18, W27 and W28, and W39
and W40 configure the half-bridge completion network for
channels 0 through 3, respectively.
Further configuration of the board is software controlled and will be
discussed later in this chapter.
Digital Signal Connections
The SCXI-1121 has three jumpers dedicated for communication between
the data acquisition board and the SCXIbus. These jumpers are W32, W38,
and W44.
Jumper W44
Position 1 on Revision A and B modules connects, after buffering,
SLOT0SEL* to the SCXIbus INTR* line. This is the factory-default setting
and should not be changed. In this setting, the data acquisition board
controls the SCXIbus INTR* line. See the Timing Requirements and
Communication Protocol section later in this chapter, and Chapter 5,
Programming, for information on the use of the INTR* line. See
Appendix E, SCXI-1121 Cabling, for the pin equivalences of the
SCXI-1121 rear signal connector and the data acquisition board
I/O connector.
Position 3 is reserved and should not be used. This position is not explicitly
marked on the module.