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/**
 * @author Aaron Berk
 *
 * @section LICENSE
 *
 * Copyright (c) 2010 ARM Limited
 *
 * 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.
 *
 * @section DESCRIPTION
 *
 * ADXL345, triple axis, digital interface, accelerometer.
 *
 * Datasheet:
 *
 * http://www.analog.com/static/imported-files/data_sheets/ADXL345.pdf
 */  

#ifndef ADXL345_H
#define ADXL345_H

/**
 * Includes
 */
#include "mbed.h"

/**
 * Defines
 */
//Registers.
#define ADXL345_DEVID_REG          0x00
#define ADXL345_THRESH_TAP_REG     0x1D
#define ADXL345_OFSX_REG           0x1E
#define ADXL345_OFSY_REG           0x1F
#define ADXL345_OFSZ_REG           0x20
#define ADXL345_DUR_REG            0x21
#define ADXL345_LATENT_REG         0x22
#define ADXL345_WINDOW_REG         0x23
#define ADXL345_THRESH_ACT_REG     0x24
#define ADXL345_THRESH_INACT_REG   0x25
#define ADXL345_TIME_INACT_REG     0x26
#define ADXL345_ACT_INACT_CTL_REG  0x27
#define ADXL345_THRESH_FF_REG      0x28
#define ADXL345_TIME_FF_REG        0x29
#define ADXL345_TAP_AXES_REG       0x2A
#define ADXL345_ACT_TAP_STATUS_REG 0x2B
#define ADXL345_BW_RATE_REG        0x2C
#define ADXL345_POWER_CTL_REG      0x2D
#define ADXL345_INT_ENABLE_REG     0x2E
#define ADXL345_INT_MAP_REG        0x2F
#define ADXL345_INT_SOURCE_REG     0x30
#define ADXL345_DATA_FORMAT_REG    0x31
#define ADXL345_DATAX0_REG         0x32
#define ADXL345_DATAX1_REG         0x33
#define ADXL345_DATAY0_REG         0x34
#define ADXL345_DATAY1_REG         0x35
#define ADXL345_DATAZ0_REG         0x36
#define ADXL345_DATAZ1_REG         0x37
#define ADXL345_FIFO_CTL           0x38
#define ADXL345_FIFO_STATUS        0x39

//Data rate codes.
#define ADXL345_3200HZ      0x0F
#define ADXL345_1600HZ      0x0E
#define ADXL345_800HZ       0x0D
#define ADXL345_400HZ       0x0C
#define ADXL345_200HZ       0x0B
#define ADXL345_100HZ       0x0A
#define ADXL345_50HZ        0x09
#define ADXL345_25HZ        0x08
#define ADXL345_12HZ5       0x07
#define ADXL345_6HZ25       0x06

#define ADXL345_SPI_READ    0x80
#define ADXL345_SPI_WRITE   0x00
#define ADXL345_MULTI_BYTE  0x60

#define ADXL345_X           0x00
#define ADXL345_Y           0x01
#define ADXL345_Z           0x02

/**
 * ADXL345 triple axis, digital interface, accelerometer.
 */
class ADXL345 {

public:

    /**
     * Constructor.
     *
     * @param mosi mbed pin to use for MOSI line of SPI interface.
     * @param miso mbed pin to use for MISO line of SPI interface.
     * @param sck mbed pin to use for SCK line of SPI interface.
     * @param cs mbed pin to use for not chip select line of SPI interface.
     */
    ADXL345(PinName mosi, PinName miso, PinName sck, PinName cs);

    /**
     * Read the device ID register on the device.
     *
     * @return The device ID code [0xE5]
     */
    int getDevId(void);

    /**
     * Read the tap threshold on the device.
     *
     * @return The tap threshold as an 8-bit number with a scale factor of
     *         62.5mg/LSB.
     */
    int getTapThreshold(void);

    /**
     * Set the tap threshold.
     *
     * @param The tap threshold as an 8-bit number with a scale factor of
     *        62.5mg/LSB.
     */
    void setTapThreshold(int threshold);

    /**
     * Get the current offset for a particular axis.
     *
     * @param axis 0x00 -> X-axis
     *             0x01 -> Y-axis
     *             0x02 -> Z-axis
     * @return The current offset as an 8-bit 2's complement number with scale
     *         factor 15.6mg/LSB.
     */
    int getOffset(int axis);

    /**
     * Set the offset for a particular axis.
     *
     * @param axis 0x00 -> X-axis
     *             0x01 -> Y-axis
     *             0x02 -> Z-axis
     * @param offset The offset as an 8-bit 2's complement number with scale
     *               factor 15.6mg/LSB.
     */
    void setOffset(int axis, char offset);

    /**
     * Get the tap duration required to trigger an event.
     *
     * @return The max time that an event must be above the tap threshold to
     *         qualify as a tap event, in microseconds.
     */
    int getTapDuration(void);

    /**
     * Set the tap duration required to trigger an event.
     *
     * @param duration_us The max time that an event must be above the tap
     *                    threshold to qualify as a tap event, in microseconds.
     *                    Time will be normalized by the scale factor which is
     *                    625us/LSB. A value of 0 disables the single/double
     *                    tap functions.
     */
    void setTapDuration(int duration_us);

    /**
     * Get the tap latency between the detection of a tap and the time window.
     *
     * @return The wait time from the detection of a tap event to the start of
     *         the time window during which a possible second tap event can be
     *         detected in milliseconds.
     */
    float getTapLatency(void);

    /**
     * Set the tap latency between the detection of a tap and the time window.
     *
     * @param latency_ms The wait time from the detection of a tap event to the
     *                   start of the time window during which a possible
     *                   second tap event can be detected in milliseconds.
     *                   A value of 0 disables the double tap function.
     */
    void setTapLatency(int latency_ms);

    /**
     * Get the time of window between tap latency and a double tap.
     *
     * @return The amount of time after the expiration of the latency time
     *         during which a second valid tap can begin, in milliseconds.
     */
    float getWindowTime(void);

    /**
     * Set the time of the window between tap latency and a double tap.
     *
     * @param window_ms The amount of time after the expiration of the latency
     *                  time during which a second valid tap can begin,
     *                  in milliseconds.
     */
    void setWindowTime(int window_ms);

    /**
     * Get the threshold value for detecting activity.
     *
     * @return The threshold value for detecting activity as an 8-bit number.
     *         Scale factor is 62.5mg/LSB.
     */
    int getActivityThreshold(void);

    /**
     * Set the threshold value for detecting activity.
     *
     * @param threshold The threshold value for detecting activity as an 8-bit
     *                  number. Scale factor is 62.5mg/LSB. A value of 0 may
     *                  result in undesirable behavior if the activity
     *                  interrupt is enabled.
     */
    void setActivityThreshold(int threshold);

    /**
     * Get the threshold value for detecting inactivity.
     *
     * @return The threshold value for detecting inactivity as an 8-bit number.
     *         Scale factor is 62.5mg/LSB.
     */
    int getInactivityThreshold(void);

    /**
     * Set the threshold value for detecting inactivity.
     *
     * @param threshold The threshold value for detecting inactivity as an
     *                  8-bit number. Scale factor is 62.5mg/LSB.
     */
    void setInactivityThreshold(int threshold);

    /**
     * Get the time required for inactivity to be declared.
     *
     * @return The amount of time that acceleration must be less than the
     *         inactivity threshold for inactivity to be declared, in
     *         seconds.
     */
    int getTimeInactivity(void);
    
    /**
     * Set the time required for inactivity to be declared.
     *
     * @param inactivity The amount of time that acceleration must be less than
     *                   the inactivity threshold for inactivity to be
     *                   declared, in seconds. A value of 0 results in an
     *                   interrupt when the output data is less than the
     *                   threshold inactivity.
     */
    void setTimeInactivity(int timeInactivity);
    
    /**
     * Get the activity/inactivity control settings.
     *
     *      D7            D6             D5            D4
     * +-----------+--------------+--------------+--------------+
     * | ACT ac/dc | ACT_X enable | ACT_Y enable | ACT_Z enable |
     * +-----------+--------------+--------------+--------------+
     *
     *        D3             D2               D1              D0
     * +-------------+----------------+----------------+----------------+
     * | INACT ac/dc | INACT_X enable | INACT_Y enable | INACT_Z enable |
     * +-------------+----------------+----------------+----------------+
     *
     * See datasheet for details.
     *
     * @return The contents of the ACT_INACT_CTL register.
     */
    int getActivityInactivityControl(void);
    
    /**
     * Set the activity/inactivity control settings.
     *
     *      D7            D6             D5            D4
     * +-----------+--------------+--------------+--------------+
     * | ACT ac/dc | ACT_X enable | ACT_Y enable | ACT_Z enable |
     * +-----------+--------------+--------------+--------------+
     *
     *        D3             D2               D1              D0
     * +-------------+----------------+----------------+----------------+
     * | INACT ac/dc | INACT_X enable | INACT_Y enable | INACT_Z enable |
     * +-------------+----------------+----------------+----------------+
     *
     * See datasheet for details.
     *
     * @param settings The control byte to write to the ACT_INACT_CTL register.
     */
    void setActivityInactivityControl(int settings);
    
    /**
     * Get the threshold for free fall detection.
     *
     * @return The threshold value for free-fall detection, as an 8-bit number,
     *         with scale factor 62.5mg/LSB.
     */
    int getFreefallThreshold(void);
    
    /**
     * Set the threshold for free fall detection.
     *
     * @return The threshold value for free-fall detection, as an 8-bit number,
     *         with scale factor 62.5mg/LSB. A value of 0 may result in 
     *         undesirable behavior if the free-fall interrupt is enabled.
     *         Values between 300 mg and 600 mg (0x05 to 0x09) are recommended.
     */
    void setFreefallThreshold(int threshold);
    
    /**
     * Get the time required to generate a free fall interrupt.
     *
     * @return The minimum time that the value of all axes must be less than
     *         the freefall threshold to generate a free-fall interrupt, in
     *         milliseconds.
     */
    int getFreefallTime(void);
    
    /**
     * Set the time required to generate a free fall interrupt.
     *
     * @return The minimum time that the value of all axes must be less than
     *         the freefall threshold to generate a free-fall interrupt, in
     *         milliseconds. A value of 0 may result in undesirable behavior
     *         if the free-fall interrupt is enabled. Values between 100 ms 
     *         and 350 ms (0x14 to 0x46) are recommended.
     */
    void setFreefallTime(int freefallTime_ms);
    
    /**
     * Get the axis tap settings.
     *
     *      D3           D2            D1             D0
     * +----------+--------------+--------------+--------------+
     * | Suppress | TAP_X enable | TAP_Y enable | TAP_Z enable |
     * +----------+--------------+--------------+--------------+
     *
     * (D7-D4 are 0s).
     *
     * See datasheet for more details.
     *
     * @return The contents of the TAP_AXES register.
     */ 
    int getTapAxisControl(void);
    
    /**
     * Set the axis tap settings.
     *
     *      D3           D2            D1             D0
     * +----------+--------------+--------------+--------------+
     * | Suppress | TAP_X enable | TAP_Y enable | TAP_Z enable |
     * +----------+--------------+--------------+--------------+
     *
     * (D7-D4 are 0s).
     *
     * See datasheet for more details.
     *
     * @param The control byte to write to the TAP_AXES register.
     */
    void setTapAxisControl(int settings);
    
    /**
     * Get the source of a tap.
     *
     * @return The contents of the ACT_TAP_STATUS register.
     */
    int getTapSource(void);
    
    /**
     * Set the power mode.
     *
     * @param mode 0 -> Normal operation.
     *             1 -> Reduced power operation.
     */
    void setPowerMode(char mode);
    
    /**
     * Set the data rate.
     *
     * @param rate The rate code (see #defines or datasheet).
     */
    void setDataRate(int rate);
    
    /**
     * Get the power control settings.
     *
     * See datasheet for details.
     *
     * @return The contents of the POWER_CTL register.
     */
    int getPowerControl(void);
    
    /**
     * Set the power control settings.
     *
     * See datasheet for details.
     *
     * @param The control byte to write to the POWER_CTL register.
     */
    void setPowerControl(int settings);
    
    /**
     * Get the interrupt enable settings.
     *
     * @return The contents of the INT_ENABLE register.
     */
    int getInterruptEnableControl(void);
    
    /**
     * Set the interrupt enable settings.
     *
     * @param settings The control byte to write to the INT_ENABLE register.
     */
    void setInterruptEnableControl(int settings);
    
    /**
     * Get the interrupt mapping settings.
     *
     * @return The contents of the INT_MAP register.
     */
    int getInterruptMappingControl(void);
    
    /**
     * Set the interrupt mapping settings.
     *
     * @param settings The control byte to write to the INT_MAP register.
     */
    void setInterruptMappingControl(int settings);
    
    /**
     * Get the interrupt source.
     *
     * @return The contents of the INT_SOURCE register.
     */
    int getInterruptSource(void);
    
    /**
     * Get the data format settings.
     *
     * @return The contents of the DATA_FORMAT register.
     */
    int getDataFormatControl(void);
    
    /**
     * Set the data format settings.
     *
     * @param settings The control byte to write to the DATA_FORMAT register.
     */
    void setDataFormatControl(int settings);
    
    /**
     * Get the output of all three axes.
     *
     * @param Pointer to a buffer to hold the accelerometer value for the
     *        x-axis, y-axis and z-axis [in that order].
     */
    void getOutput(int* readings);
    
    /**
     * Get the FIFO control settings.
     *
     * @return The contents of the FIFO_CTL register.
     */
    int getFifoControl(void);
    
    /**
     * Set the FIFO control settings.
     *
     * @param The control byte to write to the FIFO_CTL register.
     */
    void setFifoControl(int settings);
    
    /**
     * Get FIFO status.
     *
     * @return The contents of the FIFO_STATUS register.
     */
    int getFifoStatus(void);
    
private:

    SPI        spi_;
    DigitalOut nCS_;

    /**
     * Read one byte from a register on the device.
     *
     * @param address Address of the register to read.
     *
     * @return The contents of the register address.
     */
    int oneByteRead(int address);

    /**
     * Write one byte to a register on the device.
     *
     * @param address Address of the register to write to.
     * @param data The data to write into the register.
     */
    void oneByteWrite(int address, char data);

    /**
     * Read several consecutive bytes on the device.
     *
     * @param startAddress The address of the first register to read from.
     * @param buffer Pointer to a buffer to store data read from the device.
     * @param size The number of bytes to read.
     */
    void multiByteRead(int startAddress, char* buffer, int size);

    /**
     * Write several consecutive bytes on the device.
     *
     * @param startAddress The address of the first register to write to.
     * @param buffer Pointer to a buffer which contains the data to write.
     * @param size The number of bytes to write.
     */
    void multiByteWrite(int startAddress, char* buffer, int size);

};

#endif /* ADXL345_H */