From 9f1a9a07c9402b7edf1a9fb3189e9307800d8680 Mon Sep 17 00:00:00 2001
From: thomasclark <tjclark@wpi.edu>
Date: Mon, 21 Jul 2014 08:57:03 -0400
Subject: [PATCH] Added a C++ built-in accelerometer class

Change-Id: I80cee788912277f06ac4bdda40261f160de0cbaa
---
 .../wpilibC++/include/BuiltInAccelerometer.h  | 30 +++++++++++
 .../wpilibC++/lib/BuiltInAccelerometer.cpp    | 53 +++++++++++++++++++
 .../src/AccelerometerTest.cpp                 | 23 ++++++++
 3 files changed, 106 insertions(+)
 create mode 100644 wpilibc/wpilibC++/include/BuiltInAccelerometer.h
 create mode 100644 wpilibc/wpilibC++/lib/BuiltInAccelerometer.cpp
 create mode 100644 wpilibc/wpilibC++IntegrationTests/src/AccelerometerTest.cpp

diff --git a/wpilibc/wpilibC++/include/BuiltInAccelerometer.h b/wpilibc/wpilibC++/include/BuiltInAccelerometer.h
new file mode 100644
index 0000000000..afcd86c53d
--- /dev/null
+++ b/wpilibc/wpilibC++/include/BuiltInAccelerometer.h
@@ -0,0 +1,30 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2014. 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 "SensorBase.h"
+
+/**
+ * Built-in accelerometer.
+ *
+ * This class allows access to the RoboRIO's internal accelerometer.
+ */
+class BuiltInAccelerometer : public SensorBase
+{
+public:
+	enum Range
+	{
+		kRange_2G = 0x00,
+		kRange_4G = 0x01,
+		kRange_8G = 0x02,
+	};
+
+	BuiltInAccelerometer(Range range = kRange_2G);
+	virtual ~BuiltInAccelerometer();
+	virtual double GetX() const;
+	virtual double GetY() const;
+	virtual double GetZ() const;
+};
diff --git a/wpilibc/wpilibC++/lib/BuiltInAccelerometer.cpp b/wpilibc/wpilibC++/lib/BuiltInAccelerometer.cpp
new file mode 100644
index 0000000000..98690ef794
--- /dev/null
+++ b/wpilibc/wpilibC++/lib/BuiltInAccelerometer.cpp
@@ -0,0 +1,53 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2014. 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.  */
+/*----------------------------------------------------------------------------*/
+
+#include "BuiltInAccelerometer.h"
+#include "HAL/HAL.hpp"
+
+/**
+ * Constructor.
+ * @param range The range the accelerometer will measure
+ */
+BuiltInAccelerometer::BuiltInAccelerometer(Range range)
+{
+	setAccelerometerActive(false);
+	setAccelerometerRange((AccelerometerRange)range);
+	setAccelerometerActive(true);
+
+	HALReport(HALUsageReporting::kResourceType_Accelerometer, 0, 0, "Built-in accelerometer");
+}
+
+/**
+ * Destructor.
+ */
+BuiltInAccelerometer::~BuiltInAccelerometer()
+{
+	setAccelerometerActive(false);
+}
+
+/**
+ * @return The acceleration of the RoboRIO along the X axis in g-forces
+ */
+double BuiltInAccelerometer::GetX() const
+{
+	return getAccelerometerX();
+}
+
+/**
+ * @return The acceleration of the RoboRIO along the Y axis in g-forces
+ */
+double BuiltInAccelerometer::GetY() const
+{
+	return getAccelerometerY();
+}
+
+/**
+ * @return The acceleration of the RoboRIO along the Z axis in g-forces
+ */
+double BuiltInAccelerometer::GetZ() const
+{
+	return getAccelerometerZ();
+}
diff --git a/wpilibc/wpilibC++IntegrationTests/src/AccelerometerTest.cpp b/wpilibc/wpilibC++IntegrationTests/src/AccelerometerTest.cpp
new file mode 100644
index 0000000000..1d9bd29ceb
--- /dev/null
+++ b/wpilibc/wpilibC++IntegrationTests/src/AccelerometerTest.cpp
@@ -0,0 +1,23 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2014. 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 the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "WPILib.h"
+#include "gtest/gtest.h"
+
+static constexpr double accelerationTolerance = 0.1;
+
+/**
+ * There's not much we can automatically test with the on-board accelerometer,
+ * but checking for gravity is probably good enough to tell that it's working.
+ */
+TEST(AccelerometerTest, Accelerometer) {
+	BuiltInAccelerometer accelerometer;
+
+	ASSERT_NEAR(0.0, accelerometer.GetX(), accelerationTolerance);
+	ASSERT_NEAR(0.0, accelerometer.GetY(), accelerationTolerance);
+	ASSERT_NEAR(1.0, accelerometer.GetZ(), accelerationTolerance);
+}