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Pfi for isolated devices, Pfi for isolated devices -2 – National Instruments Network Device DAQ S User Manual

Page 113

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Chapter 8

Programmable Function Interfaces (PFI)

NI 6124/6154 User Manual

8-2

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Each PFI input also has a programmable debouncing filter. Figure 8-1
shows the circuitry of one PFI line. Each PFI line is similar.

Figure 8-1. PFI Circuitry on Non-Isolated S Series Devices

When a terminal is used as a timing input or output signal, it is called PFI x
(where x is an integer from 0 to 15). When a terminal is used as a static
digital input or output, it is called P1.x or P2.x. On the I/O connector, each
terminal is labeled PFI x/P1.x or PFI x/P2.x.

The voltage input and output levels and the current drive levels of the PFI
signals are listed in the NI 6124 Specifications.

PFI for Isolated Devices

(NI 6154 Only)

Isolated S Series devices have 10 Programmable Function

Interface (PFI) signals—six input signals and four output signals.

Each PFI <0..5>/P0.<0..5> can be configured as a timing input signal for
AI or counter/timer functions or a static digital input. Each PFI input also
has a programmable debouncing filter.

Timing Signals

Direction Control

Static DI

I/O Protection

Weak Pull-Down

PFI x/P1 or
PFI x/P2

Static DO

Buffer

To Input Timing

Signal Selectors

PFI

Filters