Package edu.wpi.first.wpilibj

Class DutyCycle

java.lang.Object
edu.wpi.first.wpilibj.DutyCycle
All Implemented Interfaces:
Sendable, AutoCloseable
public class DutyCycle extends Object implements Sendable, AutoCloseable
Class to read a duty cycle PWM input.

PWM input signals are specified with a frequency and a ratio of high to low in that frequency. There are 8 of these in the roboRIO, and they can be attached to any DigitalSource.

These can be combined as the input of an AnalogTrigger to a Counter in order to implement rollover checking.

  • Constructor Details

    • DutyCycle

      public DutyCycle(DigitalSource digitalSource)
      Constructs a DutyCycle input from a DigitalSource input.

      This class does not own the inputted source.

      Parameters:
      digitalSource - The DigitalSource to use.

  • Method Details

    • close

      public void close()
      Close the DutyCycle and free all resources.
      Specified by:
      close in interface AutoCloseable

    • getFrequency

      public int getFrequency()
      Get the frequency of the duty cycle signal.
      Returns:
      frequency in Hertz

    • getOutput

      public double getOutput()
      Get the output ratio of the duty cycle signal.

      0 means always low, 1 means always high.

      Returns:
      output ratio between 0 and 1

    • getHighTimeNanoseconds

      public int getHighTimeNanoseconds()
      Get the raw high time of the duty cycle signal.
      Returns:
      high time of last pulse in nanoseconds

    • getOutputScaleFactor

      public int getOutputScaleFactor()
      Get the scale factor of the output.

      An output equal to this value is always high, and then linearly scales down to 0. Divide a raw result by this in order to get the percentage between 0 and 1. Used by DMA.

      Returns:
      the output scale factor

    • getFPGAIndex

      public final int getFPGAIndex()
      Get the FPGA index for the DutyCycle.
      Returns:
      the FPGA index

    • getSourceChannel

      public int getSourceChannel()
      Get the channel of the source.
      Returns:
      the source channel

    • initSendable

      public void initSendable(SendableBuilder builder)
      Description copied from interface: Sendable
      Initializes this Sendable object.
      Specified by:
      initSendable in interface Sendable
      Parameters:
      builder - sendable builder