National Instruments 7344 Switch User Manual


 
Chapter 5 Signal Connections
7344/7334 Hardware User Manual 5-10 ni.com
edge. You can also use a trigger input as a latching general-purpose
digital input by simply ignoring the captured position.
Shutdown InputThe shutdown input signal, when enabled in
software, can be used to kill all motion by asserting the controller
inhibits, setting the analog outputs to 0 V, and stopping any stepper
pulse generation. To activate shutdown, thesignal must transition from
a low to high state (rising edge).
Breakpoint Output <1..4>A breakpoint output can be programmed
to transition when the associated encoder value equals the breakpoint
position. You can use a breakpoint output to directly control actuators
or as a trigger to synchronize data acquisition or other functions in the
motion control system.
You can program breakpoints as either absolute, modulo,orrelative
position. Breakpoint outputs can be preset to a known state so that the
transition when the breakpoint occurs can be low to high, high to low,
or toggle.
The breakpoint outputs are driven by open-collector TTL buffers that
feature 64 mA sink current capability and built in 3.3 kpull-up
resistors to +5 V.
You can directly set and reset breakpoint outputs so you can use them
as general-purpose digital outputs.
Wiring Concerns
Caution
Keep trigger input, shutdown input, and breakpoint output signals and their
ground connections wired separately from the motor driver/amplifier signal and encoder
signal connections. Wiring these signals near each other can cause faulty operation.
Excessive input voltages can cause erroneous operation and/or component failure.