FP-CTR-500 and cFP-CTR-500
16
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3. Subtract 1 from the value that you want to divide the count
input by and set the Terminal Count of the pulse counter to the
result.
The internal output from the pulse counter triggers the output
channel that you selected for the pulse train output.
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
f
pulse
f
pre
term
pulse
1
+
--------------------------------
=
d
1
term
pulse
1
+
--------------------------------
=
d
1
1
term
pulse
1
+
--------------------------------
–
=