User manual

Chapter 4 Connecting Signals
NI 6034E/6035E/6036E User Manual 4-24 ni.com
EXTSTROBE* Signal
EXTSTROBE* is an output-only signal that generates either a single pulse
or a sequence of eight pulses in the hardware-strobe mode. An external
device can use this signal to latch signals or to trigger events. In the
single-pulse mode, software controls the level of the EXTSTROBE*
signal. A 10 µs and a 1.2 µs clock are available for generating a sequence
of eight pulses in the hardware-strobe mode.
Figure 4-14 shows the timing for the hardware-strobe mode
EXTSTROBE* signal.
Figure 4-14. EXTSTROBE* Signal Timing
TRIG1 Signal
Any PFI pin can externally input the TRIG1 signal, which is available as
an output on the PFI0/TRIG1 pin.
Refer to Figures 4-11 and 4-12 for the relationship of TRIG1 to the DAQ
sequence.
As an input, the TRIG1 signal is configured in the edge-detection mode.
You can select any PFI pin as the source for TRIG1 and configure the
polarity selection for either rising or falling edge. The selected edge of the
TRIG1 signal starts the data acquisition sequence for both posttriggered
and pretriggered acquisitions.
As an output, the TRIG1 signal reflects the action that initiates a DAQ
sequence, even if the acquisition is being externally triggered by another
PFI. The output is an active high pulse with a pulse width of 50 to 100 ns.
This output is set to tri-state at startup.
V
OH
V
OL
t
w
t
w
t
w
=600 ns or 500 s
UM.book Page 24 Monday, May 14, 2001 10:32 AM