Pfi - National Instruments Data Acquisition Device NI USB-621x User Manual

PFI

Note (USB-6212/6216 Devices)
as input or output.
PFI/DIO Pin
I/O Protection
© National Instruments Corporation
USB-621x devices have multiple Programmable Function Interface (PFI)
signals.
Each input PFI can be individually configured as the following:
• A static digital input
• A timing input signal for AI, AO, or counter/timer functions
Each output PFI can be individually configured as the following:
• A static digital output
• A timing output signal from AI, AO, or counter/timer functions
PFI signals on USB-6212/6216 devices can be configured
Each PFI input also has a programmable debouncing filter. Figure 7-1
shows the circuitry of an input PFI line.
Weak Pull-Down
Static DI
(USB-6215/
6216/6218
devices only)
PFI
Filters
Figure 7-1. USB-621x PFI Input Circuitry
7-1
Isolation
Barrier
Digital
To Input Timing
Isolators
Signal Selectors
NI USB-621x User Manual
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