Chapter 4
Signal Connections
4-4
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TRIG<3..0>
Triggers <3..0> are TTL I/O lines used to start or stop an acquisition or output
an acquisition status. You can program the triggers to be rising- or falling-edge
sensitive. You can also program the triggers to be programmatically asserted or
unasserted similar in function to a digital I/O line or to contain internal status
signals (by using the onboard events) or specific pulse widths.
CTRL<3..0>±
Use the control lines on the PCI-1409 to control camera features and timing
information. Either static or dynamic, TTL or differential, signals can be
generated on these lines to perform such functions as generating integration or
shutter pulses to the cameras.
GND
GND is a direct connection to digital GND on the 1409 device.
CHASSIS_GND
CHASSIS_GND is a direct connection to the computer’s chassis, which is
grounded through the power cord.
Table 4-1.
I/O Connector Signals (Continued)
Signal Name
Description
