Diff: MMA7455.h

Revision:

4:b32cf4ef45c5

Child:

12:15597e45eea0

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MMA7455.h	Fri Oct 18 12:48:58 2013 +0200
@@ -0,0 +1,94 @@
+
+#ifndef MMA7455_H
+#define MMA7455_H
+
+
+/**
+ * Freescale Accelerometer MMA7455.
+ */
+class MMA7455 {
+public:
+
+    enum Mode {
+        ModeStandby = 0,
+        ModeMeasurement = 1,
+    };
+
+    /** Acceleration range */
+    enum Range {
+        Range_8g = 0,
+        Range_2g = 1,
+        Range_4g = 2
+    };
+
+    /**
+     * Create an interface to the MMA7455 accelerometer
+     *
+     * @param sda I2C data line pin
+     * @param scl I2C clock line pin
+     */
+    MMA7455(PinName sda, PinName scl);
+
+    bool setMode(Mode mode);
+    bool setRange(Range range);
+
+    bool read(int32_t& x, int32_t& y, int32_t& z);
+
+    /**
+     * Calibrate for 0g, that is, calculate offset to achieve
+     * 0g values when accelerometer is placed on flat surface.
+     *
+     * Please make sure the accelerometer is placed on a flat surface before
+     * calling this function.
+     *
+     * @return true if request was successful; otherwise false
+     */
+    bool calibrate();
+
+    /**
+     * Get calculated offset values. Offsets will be calculated by the
+     * calibrate() method.
+     *
+     * Use these values and put them in persistent storage to avoid
+     * having to calibrate the accelerometer after a reset/power cycle.
+     *
+     * @param xOff x offset is written to this argument
+     * @param yOff y offset is written to this argument
+     * @param zOff z offset is written to this argument
+     *
+     * @return true if request was successful; otherwise false
+     */
+    bool getCalibrationOffsets(int32_t& xOff, int32_t& yOff, int32_t& zOff);
+
+    /**
+     * Set calibration offset values. These values should normally
+     * at one point in time have been retrieved by calling the
+     * getCalibrationOffsets method.
+     *
+     *
+     * @param xOff x offset
+     * @param yOff y offset
+     * @param zOff z offset
+     *
+     * @return true if request was successful; otherwise false
+     */
+    bool setCalibrationOffsets(int32_t xOff, int32_t yOff, int32_t zOff);
+
+
+
+private:
+
+    I2C _i2c;
+    Mode _mode;
+    Range _range;
+    int32_t _xOff;
+    int32_t _yOff;
+    int32_t _zOff;
+
+    int getStatus();
+    int getModeControl();
+    int setModeControl(uint8_t mctl);
+
+};
+
+#endif