©
National Instruments Corp.
15
FP-CTR-502 and cFP-CTR-502
To determine the frequency of the output from the pulse counter,
use the following formula:
where
f
pulse
is the pulse counter output frequency
f
pre
is the prescaler counter output frequency
term
pulse
is the terminal count value for the pulse counter
Step 3. Configure the Pulse Train Output Channel
To configure the pulse train output channel, complete the following
steps:
1. For the output channel that you selected, set the Output Source
to the pulse-counter channel.
2. Set the Output Mode of the output channel. To generate a pulse
train with variable duty cycle, use one of the pulse modes—On
Pulse or Off Pulse. To generate a 50% duty-cycle pulse train,
use one of the toggle modes.
To determine the duty cycle, use the following formulas:
For On Pulse mode, use
For Off Pulse mode, use
where
d
is the duty cycle of the pulse train
term
pulse
is the terminal count value of the pulse counter
When you set the output to one of the pulse modes, the frequency
of the pulse train (
f
pulse
) is the same as that shown in
, but the output frequency is half that value when
you set the output channel to one of the toggle modes.
f
pulse
f
pre
term
pulse
1
+
--------------------------------
=
d
1
term
pulse
1
+
--------------------------------
=
d
1
1
term
pulse
1
+
--------------------------------
–
=
Summary of Contents for FieldPoint FP-CTR-502
Page 1: ...cFP CTR 502...
