National Instruments 636 Series User Manual

© National Instruments | 8-1
8
PFI
X Series devices have up to 16 Programmable Function Interface (PFI) signals. In addition,
X Series devices have up to 32 lines of bidirectional DIO signals.
Each PFI can be individually configured as the following:
• A static digital input
• A static digital output
• A timing input signal for AI, AO, DI, DO, or counter/timer functions
• A timing output signal from AI, AO, DI, DO, or counter/timer functions
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. X Series PFI Circuitry
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 device specifications
Timing Signals
Direction
Control
I/O Protection
Weak Pull-Down
PFI
x/P1/P2
Static DO
Buffer
To Input Timing
Signal Selectors
PFI
Filters
Static DI
PFI
Change
Detection

National Instruments 636 Series Specifications

General

Brand	National Instruments
Model	636 Series
Category	Data Loggers
Language	English