adxl335: Initial implementation

The was tested with the Grove 3-Axis Analog Gyro.

Signed-off-by: Jon Trulson <jtrulson@ics.com>
Signed-off-by: Zion Orent <zorent@ics.com>
Signed-off-by: John Van Drasek <john.r.van.drasek@intel.com>

src/adxl335/adxl335.h

@@ -0,0 +1,119 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * Adapted from the seeedstudio example
+ * https://github.com/Seeed-Studio/Accelerometer_ADXL335
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#pragma once
+
+#include <string>
+#include <mraa/aio.h>
+
+#define ADXL335_DEFAULT_AREF 5.0
+#define ADXL335_SENSITIVITY 0.25 // 0.25v/g
+
+namespace upm {
+
+  /**
+   * @brief C++ API for the ADXL335 3-axis analog acclerometer
+   *
+   * UPM module for the ADXL335 3-axis analog accelerometer.  This
+   * was tested on a Grove 3-axis Analog Accelerometer.  It uses 3
+   * analog pins, one each for X, Y, and Z axis.
+   *
+   * @ingroup grove analog
+   * @snippet adxl335.cxx Interesting
+   */
+  class ADXL335 {
+  public:
+    /**
+     * ADXL335 constructor
+     *
+     * @param pinX analog pin to use for axis X
+     * @param pinY analog pin to use for axis Y
+     * @param pinZ analog pin to use for axis Z
+     * @param aref analog voltage reference, default 5.0
+     */
+    ADXL335(int pinX, int pinY, int pinZ, float aref=ADXL335_DEFAULT_AREF);
+
+    /**
+     * ADXL335 Destructor
+     */
+    ~ADXL335();
+
+    /**
+     * Set the "zero" value of the X axis, determined through calibration
+     *
+     * @param zeroX  The "zero" value of the X axis
+     */
+    void setZeroX(float zeroX) { m_zeroX = zeroX; };
+
+    /**
+     * Set the "zero" value of the Y axis, determined through calibration
+     *
+     * @param zeroX  The "zero" value of the Y axis
+     */
+    void setZeroY(float zeroY) { m_zeroY = zeroY; };
+
+    /**
+     * Set the "zero" value of the Z axis, determined through calibration
+     *
+     * @param zeroX  The "zero" value of the Z axis
+     */
+    void setZeroZ(float zeroZ) { m_zeroZ = zeroZ; };
+
+    /**
+     * Get the analog values for the 3 axes
+     *
+     * @param xVal pointer to returned X value
+     * @param yVal pointer to returned Y value
+     * @param zVal pointer to returned Z value
+     */
+    void values(int *xVal, int *yVal, int *zVal);
+
+    /**
+     * Get the acceleration along all 3 axes
+     *
+     * @param xAccel pointer to returned X value
+     * @param yAccel pointer to returned Y value
+     * @param zAccel pointer to returned Z value
+     */
+    void acceleration(float *xAccel, float *yAccel, float *zAccel);
+
+    /**
+     * While the sensor is still, measure the X, Y, and Z values and
+     * use those values as our zero values.
+     *
+     */
+    void calibrate();
+
+  private:
+    mraa_aio_context m_aioX;
+    mraa_aio_context m_aioY;
+    mraa_aio_context m_aioZ;
+    float m_aref;
+    float m_zeroX, m_zeroY, m_zeroZ;
+  };
+}
+
+