Siemens SIMATIC S7-1200

Technology instructions
10.1 Counting (High-speed counters)
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
579
Capture input
The Capture input sets the captured count value to the count value saved at the moment you
triggered the Capture input. You can trigger the capture when the input pin is in one of the
following states:
● Goes from low to high
● Goes from high to low
● Goes from high to low or from low to high
Gate input
The Gate input stops HSC counting. You can trigger the Gate when the input pin is in one of
the following states:
● High
● Low
10.1.3.5
Output function
The compare output function is the only output for the HSC and is only available in Count
mode.
Compare output
You can configure the Compare output to generate a single pulse on the occurrence of one
of the following events:
● Counter equals reference value (count direction is up)
● Counter equals reference value (count direction is down)
● Counter equals reference value (count direction is up or down)
● Counter equals reference value 2 (count direction is up)
● Counter equals reference value 2 (count direction is down)
● Counter equals reference value 2 (count direction is up or down)
● Positive overflow
● Negative overflow
You can configure the output pulse with a cycle time ranging from 1 to 500 ms; the default
cycle time is 10 ms. You can set the pulse width, or duty cycle, anywhere from 1 to 100%;
the default pulse width is 50%.
If multiple compare output events occur within the specified cycle time, the output pulses
from those events are lost due to the fact that the current pulse has not completed its cycle
yet. Once the pulse has finished (the configured cycle time has passed), the pulse generator
is available to produce a new pulse.