User`s guide

Operation Theory • 55
Trigger Level digital setting Trigger voltage
0xFF 9.92V
0xFE 9.84V
--- ---
0x81 0.08V
0x80 0
0x7F -0.08V
--- ---
0x01 -9.92V
Table 14: Analog trigger SRC1 (EXTATRIG) ideal transfer characteristic
The trigger signal is generated when the analog trigger condition is satis-
fied. There are five analog trigger conditions in DAQ/PXI-22XX.
DAQ/PXI-22XX uses 2 threshold voltages: Low_Threshold and High_
Threshold to build the 5 different trigger conditions. Users could configure
the trigger conditions easily by software.
4.5.2.1 Below-Low analog trigger condition
Figure 40 shows the below-low analog trigger condition, the trigger signal
is generated when the input analog signal is less than the Low_Threshold
voltage, and the High_Threshold setting is not used in this trigger condi-
tion.
Figure 40: Below-Low analog trigger condition