Pleora Technologies iPORT CL-Ten, User Manual, Page: 63 / 72

59 Advanced Features Usage Examples
Using the Rescaler Feature to Change a Signal Frequency
The following procedure demonstrates how you can configure the rescaler feature to change a 16 Hz pulse
to a 1.6 Hz pulse. The
PlcCtrl0
control bit is used to stop and start the 16 Hz input to the rescaler. The
rescaler requires a timing signal to perform the conversion. In this example, Timer0 is used to generate
the 16 Hz pulse.
To configure the rescaler to change a signal frequency
1.
Follow steps 1-5 in the procedure, “To control the PLC remotely” on page 56.
2.
In the Timer section, select Timer0 from the TimerSelector list.
3.
Select TimerDurationRaw and enter 65535 to configure the duration of the 16 Hz pulse (the
length of time that the 16 Hz pulse is high).
4.
Select TimerDelayRaw and enter 65535 to set the duration of the delay before the pulse can start
(the length of time that the 16 Hz pulse is low).
5.
Select TimerTriggerSource and select Continuous to allow the timer to automatically trigger (no
source required).
6.
In the TimerGranularityFactor list, select Granularity480ns to configure the interval of the timer's
internal clock tick.
7.
In the Rescaler section, select Granularity7p68us from the PlcRescalerGranularityFactor list.
8.
In the PlcRescalerFreqMultiplierSelect list, select FrequencyX16 .
9.
Select PlcRescalerFreqDivider list and enter 160 .
10.
In the PlcRescalerBackupEnabled list, select False .
11.
In the SignalRouting section, select one of the available equations, for example, PlcEquation0 , and
enter the following Boolean equation: GpioOut0 = Rescaler0Out.
12.
In the SignalRouting section, select another of the available equations, for example, PlcEquation1 ,
and enter the following Boolean equation: Rescaler0In = Timer0Out & PlcCtrl0.
13.
Click PlcEquationApply to apply the equations.
14.
In the ControlBits section of the Plc category, select one of the inputs from the PlcCtrlSelector list,
for example, PlcCtrl0 .
15.
In the PlcCtrlValue list, click True to set the signal state to high, or False to set the signal state to
low.
When PlcCtrl0 is True , the 16 Hz signal from Timer0 passes into the rescaler and emerges as a 1.6
Hz signal. When PlcCtrl0 is False , the 16 Hz signal is interrupted; the rescaler's output stops, and
may be either a 'high' or 'low' value.