© National Instruments Corporation 9 USB-6008/6009 User Guide and Specifications
Signal Descriptions
Table5 describes the signals available on the I/O connectors.
Table 5. Signal Descriptions
Signal Name Reference Direction Description
GND — — Ground—The reference point for the
single-ended AI measurements, bias
current return point for differential mode
measurements, AO voltages, digital
signals at the I/O connector, +5VDC
supply, and the +2.5VDC reference.
AI <0..7> Vari es Input Analog Input Channels 0 to 7—For
single-ended measurements, each signal is
an analog input voltage channel. For
differential measurements, AI0 and AI 4
are the positive and negative inputs of
differential analog input channel 0.
Thefollowing signal pairs also form
differential input channels:
<AI 1, AI 5>, <AI2, AI 6>, and
<AI3,AI7>.
AO 0 GND Output Analog Channel 0 Output—Supplies the
voltage output of AO channel 0.
AO 1 GND Output Analog Channel 1 Output—Supplies the
voltage output of AO channel 1.
P1.<0..3>
P0.<0..7>
GND Input or Output Digital I/O Signals—You can
individually configure each signal as an
input or output.
+2.5 V GND Output +2.5 V External Reference—Provides a
reference for wrap-back testing.
+5 V GND Output +5 V Power Source—Provides +5V
power up to 200mA.
PFI 0 GND Input PFI 0—This pin is configurable as either a
digital trigger or an event counter input.