National Instruments 6008 - Manual (Page 15)

© National Instruments Corporation 15 NI USB-6008/6009 User Guide and Specifications
Connecting Reference Single-Ended Voltage Signals
To connect reference single-ended voltage signals (RSE) to the
NI USB-6008/6009, connect the positive voltage signal to the desired
AI terminal, and the ground signal to a GND terminal.
When no signals are connected to the analog input terminal, the internal
resistor divider may cause the terminal to float to approximately 1.4 V
when the analog input terminal is configured as RSE. This behavior is
normal and does not affect the measurement when a signal is connected.
Figure 10. Connecting a Reference Single-Ended Voltage Signal
Digital Trigger
When an AI task is defined, you can configure PFI 0 as a digital trigger
input. When the digital trigger is enabled, the AI task waits for a rising or
falling edge on PFI 0 before starting the acquisition. To use ai/Start Trigger
with a digital source, specify PFI 0 as the source and select rising or falling
edge.
AI
Voltage
Source
NI USB-6008/6009
GND