National Instruments NI 6602 User Manual

Also see for NI 6601: User manual Manual User manual User manual User manual

National Instruments NI 6602 User Manual Manual pdf 26 page image

Chapter 3 Signal Connections© National Instruments Corporation 3-3 NI 660x User Manualare t fltrclk or shorter. A pulse with a width between these two ranges may ormay not pass, depending on the phase of the pulse with respect to the filterclock timebase.Table 3-1 summarizes the properties of the different filter settings.You individually configure the filter setting for each PFI line. The filters areuseful to maintain signal integrity. They can prevent measurement errorscaused by noise, crosstalk, or transmission line effects.Note The digital filters on the NI 660x devices are not enabled by default.For more information about using the digital filters on your device, refer tothe NI-DAQmx Help.Power-On StateThe PFI lines are weakly pulled down within the NI-TIO ASIC, and theRTSI lines are weakly pulled high. Connections for pulling up the PFI linesor for stronger pull-down connections must be made external to theNI 660x. These connections affect the drive strength of the NI 660x whenthe lines pulled up or down are used as outputs.Pin AssignmentsTable 3-2 lists the pin assignments for the I/O connector on the NI 660x.Note The NI 6601 uses counters <0..3> only.Table 3-1. Filter SettingsFilter Setting Pulse Width Passed Pulse Width Blocked5 μs 5 μs 2.5 μs1 μs 1 μs 500 ns500 ns 500 ns 250 ns100 ns 100 ns 50 nsProgrammable settingwith period of clock = tfltrclk2*t fltrclk tfltrclk