Chapter 8
Programmable Function Interfaces (PFI)
©
National Instruments Corporation
8-3
Figure 8-2 shows the circuitry of one PFI input line. Each PFI line is
similar.
Figure 8-2.
PFI Input Circuitry on Isolated S Series Devices
Each PFI <6..9>/P1.<0..3> can be configured as a timing output signal
from AI or counter/timer functions or a static digital output.
Figure 8-3 shows the circuitry of one PFI output line. Each PFI line is
similar.
Figure 8-3.
PFI Output Circuitry on 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 9). When a terminal is used as a static digital
input or output, it is called P0.
x
or P1.
x
.
The voltage input and output levels and the current drive levels of the PFI
signals are listed in the
NI 6154 Specifications
.
To Inp
u
t Timing
S
ign
a
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elector
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ol
a
tion
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ol
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tor
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I/O Protection
PFI <0..5>/P0.<0..5>
PFI
Filter
s
S
t
a
tic DI
Timing
S
ign
a
l
s
I/O Protection
PFI <6..9>/P1.<0..
3
>
O
u
tp
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t
En
ab
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t
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tic DO
B
u
ffer
I
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Digit
a
l
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tor
s
Note
: One o
u
tp
u
t en
ab
le i
s
s
h
a
red
b
y
a
ll digit
a
l o
u
tp
u
t
s
ign
a
l
s
.
