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National Instruments Corporation
8-1
8
PFI
M Series devices have up to 16 Programmable Function Interface (PFI)
signals. In addition, M 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.
M Series PFI Circuitry
Timing Signals
Direction Control
Static DI
I/O Protection
Weak Pull-Down
PFI x/P1/P2
Static DO
Buffer
To Input Timing
Signal Selectors
PFI
Filters