National Instruments 1142 用户手册

© National Instruments Corporation

In parallel output mode, channel 0 is selected at the output multiplexer and 
is connected to AI 0. The seven other channels are directly connected to 
AI 1 through AI 7, respectively, on the rear connector.

In multiplexed mode, the AI 0 signal pair is used for sending all eight 
channels of the SCXI-1141/1142/1143, and analog signals from other 
modules, to the connected E/M Series DAQ device. If the module is cabled 
directly to the DAQ device, the other analog channels of the DAQ device 
are unavailable for general-purpose analog input because they are 
connected to the SCXI-1141/1142/1143 amplifier outputs. This means that 
connecting an SCXI-1180 module to the 50-pin breakout connector of the 
SCXI-1349, or other cable adapter assembly, may cause interference and 
incorrect measurements when the DAQ device is cabled to the 
SCXI-1141/1142/1143.

The communication signals between the DAQ device and the SCXI system 
are listed in Table 2-3. If the DAQ device is connected to the 
SCXI-1141/1142/1143, these digital lines are unavailable for 
general-purpose digital I/O.

Table 2-3.  SCXI-1141/1142/1143 Rear Communication Signals

5, 7, 9, 
11, 13, 

15, 17 

AI <1..7>

N/A

Output

Analog outputs—these pins are the 
outputs of channels 1 through 7, 
regardless of the scanning mode.

6, 8, 

10, 12, 
14, 16, 

18 

A GND

AI GND

—

Analog ground—these pins connect 
to the module analog ground. They 
are used as the reference points for 
AI 1 + through AI 7 +.

24, 

33

DIG GND

D GND

—

Digital ground—these pins supply 
the reference for E/M Series DAQ 
device digital signals and connect to 
the module digital ground.

25

SER DAT IN

P0.0

Input

Serial data in—this signal taps into 
the SCXIbus MOSI line to send 
serial input data to a module or 
Slot 0.