Chapter 4
Connecting Signals
©
National Instruments Corporation
4-5
PFI8/GPCTR0_SOURCE
DGND
Input
Output
PFI8/Counter 0 Source—As an input, this is a PFI. As
an output, this is the GPCTR0_SOURCE signal. This
signal reflects the actual source connected to the
general-purpose counter 0.
PFI9/GPCTR0_GATE
DGND
Input
Output
PFI9/Counter 0 Gate—As an input, this is a PFI. As an
output, this is the GPCTR0_GATE signal. This signal
reflects the actual gate signal connected to the
general-purpose counter 0.
GPCTR0_OUT
DGND
Output
1
Counter 0 Output—This output is from the
general-purpose counter 0 output.
FREQ_OUT
DGND
Output
Frequency Output—This output is from the frequency
generator output.
1
The GPCTR0_OUT acts as an input when using external clock mode with correlated DIO.
Table 4-3.
Analog I/O Signal Summary for the NI 6115
Signal Name
Signal
Type and
Direction
Impedance
Input/
Output
Protection
(Volts)
On/Off
Source
(mA at V)
Sink
(mA at V)
Rise
Time
(ns)
Bias
ACH<0..3>+
AI
1 M
Ω
in
parallel with
100 pF
1
or 10 k
Ω
in
parallel with
40 pF
2
42 V
—
—
—
±300 pA
ACH<0..3>–
AI
10 nF to
ACH<0..3>
GND
42 V
—
—
—
±300 pA
DAC0OUT
AO
50
Ω
Short-circuit
to ground
5 at 10
5 at –10
—
—
DAC1OUT
AO
50
Ω
Short-circuit
to ground
5 at 10
5 at –10
—
—
1
Applies to range
≤
±
10 V, impedance refers to ACH<0..3>–.
2
Applies to range >
±
10 V, impedance refers to ACH<0..3>–.
Table 4-2.
Signal Descriptions for I/O Connector Pins (Continued)
Signal Name
Reference
Direction
Description