Chapter 3
Digital I/O Functionality
NI CVS-1450 Series User Manual
3-8
ni.com
Using ISO Input 5 as a Latch
You can configure the product selection port to use ISO Input 5 as a latch.
A rising edge on ISO Input 5 can latch the data into a data register on the
NI CVS-1450 device. Before each inspection, the software checks the
status of the product select inputs and reads the most recent value latched
into the register.
Note
In Vision Builder AI, ISO Input 5 is always designated as a latch.
Table 3-3 lists the product selection ports.
General-Purpose I/O
General-purpose inputs and outputs are available as both TTL and isolated
connections. At any time, the software running on the NI CVS-1450 device
can read the inputs and drive the outputs high or low.
General-Purpose Inputs
The primary difference between general-purpose inputs and trigger inputs
is that you cannot use general-purpose inputs to initiate a timed pulse
generator. In an application, use the general-purpose inputs to get the status
of the inputs at a given point and not to synchronize the NI CVS-1450
device with an external event.
An example of how to use general-purpose inputs is reading the status of
a general-purpose input as the first step in your inspection sequence and
recording that value as part of your inspection.
Table 3-3.
Product Selection Port
Function
External Connection
Data(5), rising edge latch
ISO Input 5
Data(4)
ISO Input 4
Data(3)
ISO Input 3
Data(2)
ISO Input 2
Data(1)
ISO Input 1
Data(0)
ISO Input 0
