Counter n a, counter n b, and counter n z signals, Routing signals to a, b, and z counter inputs, Counter n up_down signal – National Instruments NI USB-621x User Manual
Page 108: Counter n hw arm signal, Routing signals to counter n hw arm input, Routing signals to a, b, and z counter inputs -28, Routing signals to counter n hw arm input -28
Chapter 9
Counters
9-28
ni.com
Output, Counter 0 Gate, Counter 0 Source, or Counter 1 Gate can be routed
to Counter 1 Aux.
Some of these options may not be available in some driver software.
Counter n A, Counter n B, and Counter n Z Signals
Counter n B can control the direction of counting in edge counting
applications. Use the A, B, and Z inputs to each counter when measuring
quadrature encoders or measuring two pulse encoders.
Routing Signals to A, B, and Z Counter Inputs
Each counter has independent input selectors for each of the A, B, and Z
inputs. The PFI <0..3> or PFI <8..11> signals can be routed to each input.
Counter n Up_Down Signal
Counter n Up_Down is another name for the Counter n B signal.
Counter n HW Arm Signal
The Counter n HW Arm signal enables a counter to begin an input or output
function.
To begin any counter input or output function, you must first enable, or arm,
the counter. In some applications, such as buffered semi-period
measurement, the counter begins counting when it is armed. In other
applications, such as single pulse-width measurement, the counter begins
waiting for the Gate signal when it is armed. Counter output operations can
use the arm signal in addition to a start trigger.
Software can arm counters or configure counters to be armed on the
assertion of the Counter n HW Arm signal.
Routing Signals to Counter n HW Arm Input
Any of the following signals can be routed to the Counter n HW Arm input.
•
PFI <0..3>, PFI <8..11>
•
ai/ReferenceTrigger
•
ai/StartTrigger
Counter 1 Internal Output can be routed to Counter 0 HW Arm.
Counter 0 Internal Output can be routed to Counter 1 HW Arm.