1 /*
2  * Author: Mihai Tudor Panu <mihai.tudor.panu@intel.com>
3  * Copyright (c) 2014 Intel Corporation.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sublicense, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be
14  * included in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  */
24 #pragma once
25 
26 #include <mraa/i2c.hpp>
27 
28 #define READ_BUFFER_LENGTH 6
29 
30 namespace upm {
31 
32 /**
33  * @brief ADXL345 Accelerometer library
34  * @defgroup adxl345 libupm-adxl345
35  * @ingroup seeed i2c accelerometer
36  */
37 
38 /**
39  * @library adxl345
40  * @sensor adxl345
41  * @comname ADXL345 3-Axis Digital Accelerometer
42  * @altname Grove 3-Axis Digital Accelerometer (16g)
43  * @type accelerometer
44  * @man seeed
45  * @con i2c
46  *
47  * @brief API for the ADXL345 3-Axis Digital Accelerometer
48  *
49  * ADXL345 is a 3-axis digital accelerometer.
50  * (http://www.seeedstudio.com/wiki/images/2/2c/ADXL345_datasheet.pdf)
51  * The sensor has configurable resolutions to measure ±2g, ±4g, ±8g, or ±16g.
52  * Note: The Grove* version of the sensor is incompatible with and not detected
53  * on the I2C bus by the Intel(R) Edison using an Arduino* breakout board at 5V
54  * (3V works fine).
55  *
56  * @image html adxl345.jpeg
57  * @snippet adxl345.cxx Interesting
58  */
59 class Adxl345 {
60 public:
61     /**
62      * Creates an ADXL345 object
63      *
64      * @param bus Number of the used I2C bus
65      */
66     Adxl345(int bus);
67 
68     /**
69      * there is no need for a ADXL345 object destructor
70      * ~Adxl345();
71      */
72 
73     /**
74      * Returns a pointer to a float[3] that contains acceleration (g) forces
75      *
76      * @return float* to a float[3]
77      */
78     float* getAcceleration();
79 
80     /**
81      * Returns a pointer to an int[3] that contains the raw register values
82      * for X, Y, and Z
83      *
84      * @return int* to an int[3]
85      */
86     int16_t* getRawValues();
87 
88     /**
89      * Returns the scale the accelerometer is currently set up to: 2, 4, 8,
90      * or 16
91      *
92      * @return uint with the current scale value
93      */
94     uint8_t getScale();
95 
96     /**
97      * Updates the acceleration values from the I2C bus
98      *
99      * @return 0 if successful
100      */
101     mraa::Result update();
102 private:
103     float m_accel[3];
104     float m_offsets[3];
105     int16_t m_rawaccel[3];
106     uint8_t m_buffer[READ_BUFFER_LENGTH];
107     mraa::I2c m_i2c;
108 };
109 
110 }
111