© National Instruments | 5-35NI cDAQ-9181/9184/9188/9191 User ManualCounter n Aux SignalThe Counter n Aux signal indicates the first edge in a two-signal edge-separation measurement.Routing a Signal to Counter n AuxEach counter has independent input selectors for the Counter n Aux signal. Any of the followingsignals can be routed to the Counter n Aux input:• Any PFI terminal• AI Reference Trigger• AI Start Trigger• Analog Comparison Event• Change Detection EventIn addition, a counter’s Internal Output, Gate or Source can be routed to a different counter’sAux. A counter’s own gate can also be routed to its Aux input.Some of these options may not be available in some driver software. Refer to the Device Routingin MAX topic in the NI-DAQmx Help or the LabVIEW Help for more information about availablerouting options.Counter n A, Counter n B, and Counter n Z SignalsCounter 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 pulseencoders.Routing Signals to A, B, and Z Counter InputsEach counter has independent input selectors for each of the A, B, and Z inputs. Any of thefollowing signals can be routed to each input:• Any PFI terminal• Analog Comparison EventRouting Counter n Z Signal to an Output TerminalYou can route Counter n Z out to any PFI terminal.Counter n Up_Down SignalCounter n Up_Down is another name for the Counter n B signal.Counter n HW Arm SignalThe 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 someapplications, such as a buffered edge count, the counter begins counting when it is armed. In
