artf4700: Added DigitalGlitchFilter

Initial Java support from Tyler Veness.
Final java support done by Jerry Morrison.

Change-Id: I1f85eb555f9ea4c0250c4c6729d7c51a76f5bef4

wpilibc/Athena/include/Counter.h

@@ -14,6 +14,8 @@
 
 #include <memory>
 
+class DigitalGlitchFilter;
+
 /**
  * Class for counting the number of ticks on a digital input channel.
  * This is a general purpose class for counting repetitive events. It can return
@@ -119,4 +121,5 @@ class Counter : public SensorBase,
   uint32_t m_index = 0;            ///< The index of this counter.
 
   std::shared_ptr<ITable> m_table;
+  friend class DigitalGlitchFilter;
 };

wpilibc/Athena/include/DigitalGlitchFilter.h

@@ -0,0 +1,50 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in $(WIND_BASE)/WPILib.  */
+/*----------------------------------------------------------------------------*/
+#pragma once
+
+#include <array>
+
+#include "HAL/cpp/priority_mutex.h"
+#include "DigitalSource.h"
+
+class Encoder;
+class Counter;
+
+/**
+ * Class to enable glitch filtering on a set of digital inputs.
+ * This class will manage adding and removing digital inputs from a FPGA glitch
+ * filter. The filter lets the user configure the time that an input must remain
+ * high or low before it is classified as high or low.
+ */
+class DigitalGlitchFilter : public SensorBase {
+ public:
+  DigitalGlitchFilter();
+  ~DigitalGlitchFilter();
+
+  void Add(DigitalSource *input);
+  void Add(Encoder *input);
+  void Add(Counter *input);
+
+  void Remove(DigitalSource *input);
+  void Remove(Encoder *input);
+  void Remove(Counter *input);
+
+  void SetPeriodCycles(uint32_t fpga_cycles);
+  void SetPeriodNanoSeconds(uint64_t nanoseconds);
+
+  uint32_t GetPeriodCycles();
+  uint64_t GetPeriodNanoSeconds();
+
+ private:
+  // Sets the filter for the input to be the requested index.  A value of 0
+  // disables the filter, and the filter value must be between 1 and 3,
+  // inclusive.
+  void DoAdd(DigitalSource *input, int requested_index);
+
+  int m_channelIndex = -1;
+  static priority_mutex m_mutex;
+  static ::std::array<bool, 3> m_filterAllocated;
+};

wpilibc/Athena/include/DigitalInput.h

@@ -12,6 +12,8 @@
 #include <memory>
 #include <cstdint>
 
+class DigitalGlitchFilter;
+
 /**
  * Class to read a digital input.
  * This class will read digital inputs and return the current value on the
@@ -45,4 +47,5 @@ class DigitalInput : public DigitalSource, public LiveWindowSendable {
   uint32_t m_channel;
 
   std::shared_ptr<ITable> m_table;
+  friend class DigitalGlitchFilter;
 };

wpilibc/Athena/include/Encoder.h

@@ -16,6 +16,7 @@
 #include <memory>
 
 class DigitalSource;
+class DigitalGlitchFilter;
 
 /**
  * Class to read quad encoders.
@@ -116,4 +117,5 @@ class Encoder : public SensorBase,
   int32_t m_encodingScale;         // 1x, 2x, or 4x, per the encodingType
 
   std::shared_ptr<ITable> m_table;
+  friend class DigitalGlitchFilter;
 };

wpilibc/Athena/include/NetworkCommunication/UsageReporting.h

@@ -68,6 +68,7 @@ typedef enum {
   kResourceType_VictorSP,
   kResourceType_TalonSRX,
   kResourceType_CANTalonSRX,
+  kResourceType_DigitalGlitchFilter,
 } tResourceType;
 
 typedef enum {