Chapter 2
Configuration and Installation
© National Instruments Corporation
2-25
SCXI-1120 User Manual
Rear Signal Connector Signal Descriptions
Pin
Signal Name
Description
1-2
AOGND
Analog Output Ground – Connected to the analog
reference when jumper W46 is in position AB-R0.
3-18
MCH0
±
through MCH7
±
Analog Output Channels 0 through 7 – Connects to
the data acquisition board differential analog input
channels.
19
OUTREF
Output Reference – Serves as the reference node for
the analog output channels and the temperature
sensor–in the DTS mode–in the Pseudodifferential
Reference mode. It should be connected to the
analog input sense of the NRSE data acquisition
board.
24, 33
DIG GND
Digital Ground – Supply the reference for data
acquisition board digital signals and are tied to the
module digital ground.
25
SERDATIN
Serial Data In – Taps into the SCXIbus MOSI line
to provide serial input data to a module or Slot 0.
26
SERDATOUT
Serial Data Out – Taps into the SCXIbus MISO line
to accept serial output data from a module.
27
DAQD*/A
Data Acquisition Board Data/Address Line – Taps
into the SCXIbus D*/A line to indicate to the
module whether the incoming serial stream is data
or address information.
29
SLOT0SEL*
Slot 0 Select – Taps into the SCXIbus INTR* line
to indicate whether the information on MOSI is
being sent to a module or Slot 0.
36
SCANCLK
Scan Clock – Indicates to the SCXI-1120 that a
sample has been taken by the data acquisition board
and causes the SCXI-1120 to change channels.
37
SERCLK
Serial Clock – This signal taps into the SCXIbus
SPICLK line to clock the data on the MOSI and
MISO lines.
43
RSVD
Reserved.
All other pins are not connected.
See the Timing Requirements and Communication Protocol section later in this chapter for more
detailed information on timing.
