Chapter 3
Digital I/O Functionality
©
National Instruments Corporation
3-9
NI CVS-1450 Series User Manual
General-Purpose Outputs
The primary difference between general-purpose outputs and timed pulse
outputs is that the timing of general-purpose outputs is controlled by
software rather than hardware. As a result, timing of general-purpose
outputs changes as the inspection algorithm changes, which makes
general-purpose outputs less appropriate than timed outputs for camera
control, strobe light control, and other applications that require precise
timing.
An example of using general-purpose outputs is driving a relay that turns
on an Inspection in Progress light for an operator to see while the inspection
sequence is running.
I/O for Fault Conditions
The NI CVS-1450 device recognizes the following fault conditions:
•
External shutdown, when shutdown mode is enabled
•
Watchdog timer expiration
•
Overheat
The behavior of the NI CVS-1450 device in the event of a fault condition
is dependent on configuration settings of the
SAFE MODE
DIP switch and
the software-enabled shutdown mode. Table 3-4 summarizes how user
configuration affects the behavior of the NI CVS-1450 device in the event
of a fault condition. To resume operation, address the fault condition and
reset the NI CVS-1450 device. The following sections describe each fault
condition.
