平衡车的MPU6050驱动 C.H.

Dependencies:   mbed

Fork of MPU6050_Driver_Balance by Chen Huan

mpu6050.cpp

Committer:
heroistired
Date:
2018-05-02
Revision:
1:588d4df02e56
Parent:
0:badebd32bd8b

File content as of revision 1:588d4df02e56:

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "mpu6050.h"

//////////////////////////////////////////////////////////////////////////////////   
//MPU6050驱动程序 C.H.                                 
////////////////////////////////////////////////////////////////////////////////// 


 
//初始化MPU6050
//返回值:0,成功
//    其他,错误代码
unsigned char MPU_Init(void)
{ 
    unsigned char res; 
    MPU_IIC_Init();//初始化IIC总线
    MPU_Write_Byte(MPU_PWR_MGMT1_REG,0X80); //复位MPU6050
    delay_ms(100);
    MPU_Write_Byte(MPU_PWR_MGMT1_REG,0X00); //唤醒MPU6050 
    MPU_Set_Gyro_Fsr(3);                    //陀螺仪传感器,±2000dps
    MPU_Set_Accel_Fsr(0);                   //加速度传感器,±2g
    MPU_Set_Rate(50);                       //设置采样率50Hz
    MPU_Write_Byte(MPU_INT_EN_REG,0X00);    //关闭所有中断
    MPU_Write_Byte(MPU_USER_CTRL_REG,0X00); //I2C主模式关闭
    MPU_Write_Byte(MPU_FIFO_EN_REG,0X00);   //关闭FIFO
    MPU_Write_Byte(MPU_INTBP_CFG_REG,0X80); //INT引脚低电平有效
    res=MPU_Read_Byte(MPU_DEVICE_ID_REG); 
    if(res==MPU_ADDR)//器件ID正确
    {
        MPU_Write_Byte(MPU_PWR_MGMT1_REG,0X01); //设置CLKSEL,PLL X轴为参考
        MPU_Write_Byte(MPU_PWR_MGMT2_REG,0X00); //加速度与陀螺仪都工作
        MPU_Set_Rate(50);                       //设置采样率为50Hz
    }else return 1;
    return 0;
}



//设置MPU6050陀螺仪传感器满量程范围
//fsr:0,±250dps;1,±500dps;2,±1000dps;3,±2000dps
//返回值:0,设置成功
//    其他,设置失败 
unsigned char MPU_Set_Gyro_Fsr(unsigned char fsr)
{
    return MPU_Write_Byte(MPU_GYRO_CFG_REG,fsr<<3);//设置陀螺仪满量程范围  
}
//设置MPU6050加速度传感器满量程范围
//fsr:0,±2g;1,±4g;2,±8g;3,±16g
//返回值:0,设置成功
//    其他,设置失败 
unsigned char MPU_Set_Accel_Fsr(unsigned char fsr)
{
    return MPU_Write_Byte(MPU_ACCEL_CFG_REG,fsr<<3);//设置加速度传感器满量程范围  
}
//设置MPU6050的数字低通滤波器
//lpf:数字低通滤波频率(Hz)
//返回值:0,设置成功
//    其他,设置失败 
unsigned char MPU_Set_LPF(unsigned short  lpf)
{
    unsigned char data=0;
    if(lpf>=188)data=1;
    else if(lpf>=98)data=2;
    else if(lpf>=42)data=3;
    else if(lpf>=20)data=4;
    else if(lpf>=10)data=5;
    else data=6; 
    return MPU_Write_Byte(MPU_CFG_REG,data);//设置数字低通滤波器  
}
//设置MPU6050的采样率(假定Fs=1KHz)
//rate:4~1000(Hz)
//返回值:0,设置成功
//    其他,设置失败 
unsigned char MPU_Set_Rate(unsigned short  rate)
{
    unsigned char data;
    if(rate>1000)rate=1000;
    if(rate<4)rate=4;
    data=1000/rate-1;
    data=MPU_Write_Byte(MPU_SAMPLE_RATE_REG,data);  //设置数字低通滤波器
    return MPU_Set_LPF(rate/2); //自动设置LPF为采样率的一半
}

//得到温度值
//返回值:温度值(扩大了100倍)
short MPU_Get_Temperature(void)
{
    unsigned char buf[2]; 
    short raw;
    float temp;
    MPU_Read_Len(MPU_ADDR,MPU_TEMP_OUTH_REG,2,buf); 
    raw=((unsigned short )buf[0]<<8)|buf[1];  
    temp=36.53+((double)raw)/340;  
    return temp*100;;
}
//得到陀螺仪值(原始值)
//gx,gy,gz:陀螺仪x,y,z轴的原始读数(带符号)
//返回值:0,成功
//    其他,错误代码
unsigned char MPU_Get_Gyroscope(short *gx,short *gy,short *gz)
{
    unsigned char buf[6],res;  
    res=MPU_Read_Len(MPU_ADDR,MPU_GYRO_XOUTH_REG,6,buf);
    if(res==0)
    {
        *gx=((unsigned short )buf[0]<<8)|buf[1];  
        *gy=((unsigned short )buf[2]<<8)|buf[3];  
        *gz=((unsigned short )buf[4]<<8)|buf[5];
    }   
    return res;;
}
//得到加速度值(原始值)
//gx,gy,gz:陀螺仪x,y,z轴的原始读数(带符号)
//返回值:0,成功
//    其他,错误代码
unsigned char MPU_Get_Accelerometer(short *ax,short *ay,short *az)
{
    unsigned char buf[6],res;  
    res=MPU_Read_Len(MPU_ADDR,MPU_ACCEL_XOUTH_REG,6,buf);
    if(res==0)
    {
        *ax=((unsigned short )buf[0]<<8)|buf[1];  
        *ay=((unsigned short )buf[2]<<8)|buf[3];  
        *az=((unsigned short )buf[4]<<8)|buf[5];
    }   
    return res;;
}
//IIC连续写
//addr:器件地址 
//reg:寄存器地址
//len:写入长度
//buf:数据区
//返回值:0,正常
//    其他,错误代码
unsigned char MPU_Write_Len(unsigned char addr,unsigned char reg,unsigned char len,unsigned char *buf)
{
    unsigned char i; 
    MPU_IIC_Start(); 
    MPU_IIC_Send_Byte((addr<<1)|0);//发送器件地址+写命令 
    if(MPU_IIC_Wait_Ack())  //等待应答
    {
        MPU_IIC_Stop();      
        return 1;       
    }
    MPU_IIC_Send_Byte(reg); //写寄存器地址
    MPU_IIC_Wait_Ack();     //等待应答
    for(i=0;i<len;i++)
    {
        MPU_IIC_Send_Byte(buf[i]);  //发送数据
        if(MPU_IIC_Wait_Ack())      //等待ACK
        {
            MPU_IIC_Stop();  
            return 1;        
        }       
    }    
    MPU_IIC_Stop();  
    return 0;   
} 
//IIC连续读
//addr:器件地址
//reg:要读取的寄存器地址
//len:要读取的长度
//buf:读取到的数据存储区
//返回值:0,正常
//    其他,错误代码
unsigned char MPU_Read_Len(unsigned char addr,unsigned char reg,unsigned char len,unsigned char *buf)
{ 
    MPU_IIC_Start(); 
    MPU_IIC_Send_Byte((addr<<1)|0);//发送器件地址+写命令 
    if(MPU_IIC_Wait_Ack())  //等待应答
    {
        MPU_IIC_Stop();      
        return 1;       
    }
    MPU_IIC_Send_Byte(reg); //写寄存器地址
    MPU_IIC_Wait_Ack();     //等待应答
    MPU_IIC_Start();
    MPU_IIC_Send_Byte((addr<<1)|1);//发送器件地址+读命令 
    MPU_IIC_Wait_Ack();     //等待应答 
    while(len)
    {
        if(len==1)*buf=MPU_IIC_Read_Byte(0);//读数据,发送nACK 
        else *buf=MPU_IIC_Read_Byte(1);     //读数据,发送ACK  
        len--;
        buf++; 
    }    
    MPU_IIC_Stop(); //产生一个停止条件 
    return 0;   
}
//IIC写一个字节 
//reg:寄存器地址
//data:数据
//返回值:0,正常
//    其他,错误代码
unsigned char MPU_Write_Byte(unsigned char reg,unsigned char data)                
{ 
    MPU_IIC_Start(); 
    MPU_IIC_Send_Byte((MPU_ADDR<<1)|0);//发送器件地址+写命令 
    if(MPU_IIC_Wait_Ack())  //等待应答
    {
        MPU_IIC_Stop();      
        return 1;       
    }
    MPU_IIC_Send_Byte(reg); //写寄存器地址
    MPU_IIC_Wait_Ack();     //等待应答 
    MPU_IIC_Send_Byte(data);//发送数据
    if(MPU_IIC_Wait_Ack())  //等待ACK
    {
        MPU_IIC_Stop();  
        return 1;        
    }        
    MPU_IIC_Stop();  
    return 0;
}
//IIC读一个字节 
//reg:寄存器地址 
//返回值:读到的数据
unsigned char MPU_Read_Byte(unsigned char reg)
{
    unsigned char res;
    MPU_IIC_Start(); 
    MPU_IIC_Send_Byte((MPU_ADDR<<1)|0);//发送器件地址+写命令 
    MPU_IIC_Wait_Ack();     //等待应答 
    MPU_IIC_Send_Byte(reg); //写寄存器地址
    MPU_IIC_Wait_Ack();     //等待应答
    MPU_IIC_Start();
    MPU_IIC_Send_Byte((MPU_ADDR<<1)|1);//发送器件地址+读命令 
    MPU_IIC_Wait_Ack();     //等待应答 
    res=MPU_IIC_Read_Byte(0);//读取数据,发送nACK 
    MPU_IIC_Stop();         //产生一个停止条件 
    return res;     
}/**/


//MPU IIC 延时函数
void MPU_IIC_Delay(void)
{
    //delay_us(2);
}
//初始化IIC
void MPU_IIC_Init(void)
{                        


#if defined DRIVER_MODE_BALANCE
    RCC->APB2ENR|=1<<3;     //先使能外设IO PORTC时钟                            
    GPIOB->CRL&=0X00FFFFFF; //PC11/12 推挽输出
    GPIOB->CRL|=0X33000000;    
    GPIOB->ODR|=3<<6;      //PC11,12 输出高
#elif defined DRIVER_MODE_ROTOR
    RCC->APB2ENR|=1<<3;     //先使能外设IO PORTC时钟                            
    GPIOB->CRH&=0XFFF00FFF; //PC11/12 推挽输出
    GPIOB->CRH|=0X00033000;    
    GPIOB->ODR|=3<<11;      //PC11,12 输出高
#else
#error  Target Board is not specified.
#endif
}
//产生IIC起始信号
void MPU_IIC_Start(void)
{
    MPU_SDA_OUT();     //sda线输出
    MPU_IIC_SDA=1;        
    MPU_IIC_SCL=1;
    MPU_IIC_Delay();
    MPU_IIC_SDA=0;//START:when CLK is high,DATA change form high to low 
    MPU_IIC_Delay();
    MPU_IIC_SCL=0;//钳住I2C总线,准备发送或接收数据 
}     
//产生IIC停止信号
void MPU_IIC_Stop(void)
{
    MPU_SDA_OUT();//sda线输出
    MPU_IIC_SCL=0;
    MPU_IIC_SDA=0;//STOP:when CLK is high DATA change form low to high
    MPU_IIC_Delay();
    MPU_IIC_SCL=1;  
    MPU_IIC_SDA=1;//发送I2C总线结束信号
    MPU_IIC_Delay();                                
}
//等待应答信号到来
//返回值:1,接收应答失败
//        0,接收应答成功
unsigned char MPU_IIC_Wait_Ack(void)
{
    unsigned char ucErrTime=0;
    MPU_SDA_IN();      //SDA设置为输入  
    MPU_IIC_SDA=1;MPU_IIC_Delay();     
    MPU_IIC_SCL=1;MPU_IIC_Delay();   
    while(MPU_READ_SDA)
    {
        ucErrTime++;
        if(ucErrTime>250)
        {
            MPU_IIC_Stop();
            return 1;
        }
    }
    MPU_IIC_SCL=0;//时钟输出0      
    return 0;  
} 
//产生ACK应答
void MPU_IIC_Ack(void)
{
    MPU_IIC_SCL=0;
    MPU_SDA_OUT();
    MPU_IIC_SDA=0;
    MPU_IIC_Delay();
    MPU_IIC_SCL=1;
    MPU_IIC_Delay();
    MPU_IIC_SCL=0;
}
//不产生ACK应答          
void MPU_IIC_NAck(void)
{
    MPU_IIC_SCL=0;
    MPU_SDA_OUT();
    MPU_IIC_SDA=1;
    MPU_IIC_Delay();
    MPU_IIC_SCL=1;
    MPU_IIC_Delay();
    MPU_IIC_SCL=0;
}                                        
//IIC发送一个字节
//返回从机有无应答
//1,有应答
//0,无应答           
void MPU_IIC_Send_Byte(unsigned char txd)
{                        
    unsigned char t;   
    MPU_SDA_OUT();      
    MPU_IIC_SCL=0;//拉低时钟开始数据传输
    for(t=0;t<8;t++)
    {              
        MPU_IIC_SDA=(txd&0x80)>>7;
        txd<<=1;      
        MPU_IIC_SCL=1;
        MPU_IIC_Delay(); 
        MPU_IIC_SCL=0;  
        MPU_IIC_Delay();
    }    
}       
//读1个字节,ack=1时,发送ACK,ack=0,发送nACK   
unsigned char MPU_IIC_Read_Byte(unsigned char ack)
{
    unsigned char i,receive=0;
    MPU_SDA_IN();//SDA设置为输入
    for(i=0;i<8;i++ )
    {
        MPU_IIC_SCL=0; 
        MPU_IIC_Delay();
        MPU_IIC_SCL=1;
        receive<<=1;
        if(MPU_READ_SDA)receive++;   
        MPU_IIC_Delay(); 
    }                    
    if (!ack)
        MPU_IIC_NAck();//发送nACK
    else
        MPU_IIC_Ack(); //发送ACK   
    return receive;
}

#define MPU6050                         //定义我们使用的传感器为MPU6050
#define MOTION_DRIVER_TARGET_MSP430     //定义驱动部分,采用MSP430的驱动(移植到STM32F1)

/* The following functions must be defined for this platform:
 * i2c_write(unsigned char slave_addr, unsigned char reg_addr,
 *      unsigned char length, unsigned char const *data)
 * i2c_read(unsigned char slave_addr, unsigned char reg_addr,
 *      unsigned char length, unsigned char *data)
 * delay_ms(unsigned long num_ms)
 * get_ms(unsigned long *count)
 * reg_int_cb(void (*cb)(void), unsigned char port, unsigned char pin)
 * labs(long x)
 * fabsf(float x)
 * min(int a, int b)
 */
#if defined MOTION_DRIVER_TARGET_MSP430
//#include "msp430.h"
//#include "msp430_i2c.h"
//#include "msp430_clock.h"
//#include "msp430_interrupt.h"

#define i2c_write   MPU_Write_Len
#define i2c_read    MPU_Read_Len
//#define delay_ms    delay_ms
#define get_ms      mget_ms
//static inline int reg_int_cb(struct int_param_s *int_param)
//{
//    return msp430_reg_int_cb(int_param->cb, int_param->pin, int_param->lp_exit,
//        int_param->active_low);
//}
////#define //   printf  //打印信息
////#define //   printf  //打印信息
/* labs is already defined by TI's toolchain. */
/* fabs is for doubles. fabsf is for floats. */
#define fabs        fabsf
#define min(a,b) ((a<b)?a:b)
#elif defined EMPL_TARGET_MSP430
#include "msp430.h"
#include "msp430_i2c.h"
#include "msp430_clock.h"
#include "msp430_interrupt.h"
#include "log.h"
#define i2c_write   msp430_i2c_write
#define i2c_read    msp430_i2c_read
#define delay_ms    msp430_delay_ms
#define get_ms      msp430_get_clock_ms
static inline int reg_int_cb(struct int_param_s *int_param)
{
    return msp430_reg_int_cb(int_param->cb, int_param->pin, int_param->lp_exit,
        int_param->active_low);
}
//#define //       MPL_LOGI
//#define //       MPL_LOGE
/* labs is already defined by TI's toolchain. */
/* fabs is for doubles. fabsf is for floats. */
#define fabs        fabsf
#define min(a,b) ((a<b)?a:b)
#elif defined EMPL_TARGET_UC3L0
/* Instead of using the standard TWI driver from the ASF library, we're using
 * a TWI driver that follows the slave address + register address convention.
 */
#include "twi.h"
#include "delay.h"
#include "sysclk.h"
#include "log.h"
#include "sensors_xplained.h"
#include "uc3l0_clock.h"
#define i2c_write(a, b, c, d)   twi_write(a, b, d, c)
#define i2c_read(a, b, c, d)    twi_read(a, b, d, c)
/* delay_ms is a function already defined in ASF. */
#define get_ms  uc3l0_get_clock_ms
static inline int reg_int_cb(struct int_param_s *int_param)
{
    sensor_board_irq_connect(int_param->pin, int_param->cb, int_param->arg);
    return 0;
}
//#define //       MPL_LOGI
//#define //       MPL_LOGE
/* UC3 is a 32-bit processor, so abs and labs are equivalent. */
#define labs        abs
#define fabs(x)     (((x)>0)?(x):-(x))
#else
#error  Gyro driver is missing the system layer implementations.
#endif

#if !defined MPU6050 && !defined MPU9150 && !defined MPU6500 && !defined MPU9250
#error  Which gyro are you using? Define MPUxxxx in your compiler options.
#endif

/* Time for some messy macro work. =]
 * #define MPU9150
 * is equivalent to..
 * #define MPU6050
 * #define AK8975_SECONDARY
 *
 * #define MPU9250
 * is equivalent to..
 * #define MPU6500
 * #define AK8963_SECONDARY
 */
#if defined MPU9150
#ifndef MPU6050
#define MPU6050
#endif                          /* #ifndef MPU6050 */
#if defined AK8963_SECONDARY
#error "MPU9150 and AK8963_SECONDARY cannot both be defined."
#elif !defined AK8975_SECONDARY /* #if defined AK8963_SECONDARY */
#define AK8975_SECONDARY
#endif                          /* #if defined AK8963_SECONDARY */
#elif defined MPU9250           /* #if defined MPU9150 */
#ifndef MPU6500
#define MPU6500
#endif                          /* #ifndef MPU6500 */
#if defined AK8975_SECONDARY
#error "MPU9250 and AK8975_SECONDARY cannot both be defined."
#elif !defined AK8963_SECONDARY /* #if defined AK8975_SECONDARY */
#define AK8963_SECONDARY
#endif                          /* #if defined AK8975_SECONDARY */
#endif                          /* #if defined MPU9150 */

#if defined AK8975_SECONDARY || defined AK8963_SECONDARY
#define AK89xx_SECONDARY
#else
/* #warning "No compass = less profit for Invensense. Lame." */
#endif

static int set_int_enable(unsigned char enable);

/* Hardware registers needed by driver. */
struct gyro_reg_s {
    unsigned char who_am_i;
    unsigned char rate_div;
    unsigned char lpf;
    unsigned char prod_id;
    unsigned char user_ctrl;
    unsigned char fifo_en;
    unsigned char gyro_cfg;
    unsigned char accel_cfg;
//    unsigned char accel_cfg2;
//    unsigned char lp_accel_odr;
    unsigned char motion_thr;
    unsigned char motion_dur;
    unsigned char fifo_count_h;
    unsigned char fifo_r_w;
    unsigned char raw_gyro;
    unsigned char raw_accel;
    unsigned char temp;
    unsigned char int_enable;
    unsigned char dmp_int_status;
    unsigned char int_status;
//    unsigned char accel_intel;
    unsigned char pwr_mgmt_1;
    unsigned char pwr_mgmt_2;
    unsigned char int_pin_cfg;
    unsigned char mem_r_w;
    unsigned char accel_offs;
    unsigned char i2c_mst;
    unsigned char bank_sel;
    unsigned char mem_start_addr;
    unsigned char prgm_start_h;
#if defined AK89xx_SECONDARY
    unsigned char s0_addr;
    unsigned char s0_reg;
    unsigned char s0_ctrl;
    unsigned char s1_addr;
    unsigned char s1_reg;
    unsigned char s1_ctrl;
    unsigned char s4_ctrl;
    unsigned char s0_do;
    unsigned char s1_do;
    unsigned char i2c_delay_ctrl;
    unsigned char raw_compass;
    /* The I2C_MST_VDDIO bit is in this register. */
    unsigned char yg_offs_tc;
#endif
};

/* Information specific to a particular device. */
struct hw_s {
    unsigned char addr;
    unsigned short max_fifo;
    unsigned char num_reg;
    unsigned short temp_sens;
    short temp_offset;
    unsigned short bank_size;
#if defined AK89xx_SECONDARY
    unsigned short compass_fsr;
#endif
};

/* When entering motion interrupt mode, the driver keeps track of the
 * previous state so that it can be restored at a later time.
 * TODO: This is tacky. Fix it.
 */
struct motion_int_cache_s {
    unsigned short gyro_fsr;
    unsigned char accel_fsr;
    unsigned short lpf;
    unsigned short sample_rate;
    unsigned char sensors_on;
    unsigned char fifo_sensors;
    unsigned char dmp_on;
};

/* Cached chip configuration data.
 * TODO: A lot of these can be handled with a bitmask.
 */
struct chip_cfg_s {
    /* Matches gyro_cfg >> 3 & 0x03 */
    unsigned char gyro_fsr;
    /* Matches accel_cfg >> 3 & 0x03 */
    unsigned char accel_fsr;
    /* Enabled sensors. Uses same masks as fifo_en, NOT pwr_mgmt_2. */
    unsigned char sensors;
    /* Matches config register. */
    unsigned char lpf;
    unsigned char clk_src;
    /* Sample rate, NOT rate divider. */
    unsigned short sample_rate;
    /* Matches fifo_en register. */
    unsigned char fifo_enable;
    /* Matches int enable register. */
    unsigned char int_enable;
    /* 1 if devices on auxiliary I2C bus appear on the primary. */
    unsigned char bypass_mode;
    /* 1 if half-sensitivity.
     * NOTE: This doesn't belong here, but everything else in hw_s is const,
     * and this allows us to save some precious RAM.
     */
    unsigned char accel_half;
    /* 1 if device in low-power accel-only mode. */
    unsigned char lp_accel_mode;
    /* 1 if interrupts are only triggered on motion events. */
    unsigned char int_motion_only;
    struct motion_int_cache_s cache;
    /* 1 for active low interrupts. */
    unsigned char active_low_int;
    /* 1 for latched interrupts. */
    unsigned char latched_int;
    /* 1 if DMP is enabled. */
    unsigned char dmp_on;
    /* Ensures that DMP will only be loaded once. */
    unsigned char dmp_loaded;
    /* Sampling rate used when DMP is enabled. */
    unsigned short dmp_sample_rate;
#ifdef AK89xx_SECONDARY
    /* Compass sample rate. */
    unsigned short compass_sample_rate;
    unsigned char compass_addr;
    short mag_sens_adj[3];
#endif
};

/* Information for self-test. */
struct test_s {
    unsigned long gyro_sens;
    unsigned long accel_sens;
    unsigned char reg_rate_div;
    unsigned char reg_lpf;
    unsigned char reg_gyro_fsr;
    unsigned char reg_accel_fsr;
    unsigned short wait_ms;
    unsigned char packet_thresh;
    float min_dps;
    float max_dps;
    float max_gyro_var;
    float min_g;
    float max_g;
    float max_accel_var;
};

/* Gyro driver state variables. */
struct gyro_state_s {
    const struct gyro_reg_s *reg;
    const struct hw_s *hw;
    struct chip_cfg_s chip_cfg;
    const struct test_s *test;
};

/* Filter configurations. */
enum lpf_e {
    INV_FILTER_256HZ_NOLPF2 = 0,
    INV_FILTER_188HZ,
    INV_FILTER_98HZ,
    INV_FILTER_42HZ,
    INV_FILTER_20HZ,
    INV_FILTER_10HZ,
    INV_FILTER_5HZ,
    INV_FILTER_2100HZ_NOLPF,
    NUM_FILTER
};

/* Full scale ranges. */
enum gyro_fsr_e {
    INV_FSR_250DPS = 0,
    INV_FSR_500DPS,
    INV_FSR_1000DPS,
    INV_FSR_2000DPS,
    NUM_GYRO_FSR
};

/* Full scale ranges. */
enum accel_fsr_e {
    INV_FSR_2G = 0,
    INV_FSR_4G,
    INV_FSR_8G,
    INV_FSR_16G,
    NUM_ACCEL_FSR
};

/* Clock sources. */
enum clock_sel_e {
    INV_CLK_INTERNAL = 0,
    INV_CLK_PLL,
    NUM_CLK
};

/* Low-power accel wakeup rates. */
enum lp_accel_rate_e {
#if defined MPU6050
    INV_LPA_1_25HZ,
    INV_LPA_5HZ,
    INV_LPA_20HZ,
    INV_LPA_40HZ
#elif defined MPU6500
    INV_LPA_0_3125HZ,
    INV_LPA_0_625HZ,
    INV_LPA_1_25HZ,
    INV_LPA_2_5HZ,
    INV_LPA_5HZ,
    INV_LPA_10HZ,
    INV_LPA_20HZ,
    INV_LPA_40HZ,
    INV_LPA_80HZ,
    INV_LPA_160HZ,
    INV_LPA_320HZ,
    INV_LPA_640HZ
#endif
};

#define BIT_I2C_MST_VDDIO   (0x80)
#define BIT_FIFO_EN         (0x40)
#define BIT_DMP_EN          (0x80)
#define BIT_FIFO_RST        (0x04)
#define BIT_DMP_RST         (0x08)
#define BIT_FIFO_OVERFLOW   (0x10)
#define BIT_DATA_RDY_EN     (0x01)
#define BIT_DMP_INT_EN      (0x02)
#define BIT_MOT_INT_EN      (0x40)
#define BITS_FSR            (0x18)
#define BITS_LPF            (0x07)
#define BITS_HPF            (0x07)
#define BITS_CLK            (0x07)
#define BIT_FIFO_SIZE_1024  (0x40)
#define BIT_FIFO_SIZE_2048  (0x80)
#define BIT_FIFO_SIZE_4096  (0xC0)
#define BIT_RESET           (0x80)
#define BIT_SLEEP           (0x40)
#define BIT_S0_DELAY_EN     (0x01)
#define BIT_S2_DELAY_EN     (0x04)
#define BITS_SLAVE_LENGTH   (0x0F)
#define BIT_SLAVE_BYTE_SW   (0x40)
#define BIT_SLAVE_GROUP     (0x10)
#define BIT_SLAVE_EN        (0x80)
#define BIT_I2C_READ        (0x80)
#define BITS_I2C_MASTER_DLY (0x1F)
#define BIT_AUX_IF_EN       (0x20)
#define BIT_ACTL            (0x80)
#define BIT_LATCH_EN        (0x20)
#define BIT_ANY_RD_CLR      (0x10)
#define BIT_BYPASS_EN       (0x02)
#define BITS_WOM_EN         (0xC0)
#define BIT_LPA_CYCLE       (0x20)
#define BIT_STBY_XA         (0x20)
#define BIT_STBY_YA         (0x10)
#define BIT_STBY_ZA         (0x08)
#define BIT_STBY_XG         (0x04)
#define BIT_STBY_YG         (0x02)
#define BIT_STBY_ZG         (0x01)
#define BIT_STBY_XYZA       (BIT_STBY_XA | BIT_STBY_YA | BIT_STBY_ZA)
#define BIT_STBY_XYZG       (BIT_STBY_XG | BIT_STBY_YG | BIT_STBY_ZG)

#if defined AK8975_SECONDARY
#define SUPPORTS_AK89xx_HIGH_SENS   (0x00)
#define AK89xx_FSR                  (9830)
#elif defined AK8963_SECONDARY
#define SUPPORTS_AK89xx_HIGH_SENS   (0x10)
#define AK89xx_FSR                  (4915)
#endif

#ifdef AK89xx_SECONDARY
#define AKM_REG_WHOAMI      (0x00)

#define AKM_REG_ST1         (0x02)
#define AKM_REG_HXL         (0x03)
#define AKM_REG_ST2         (0x09)

#define AKM_REG_CNTL        (0x0A)
#define AKM_REG_ASTC        (0x0C)
#define AKM_REG_ASAX        (0x10)
#define AKM_REG_ASAY        (0x11)
#define AKM_REG_ASAZ        (0x12)

#define AKM_DATA_READY      (0x01)
#define AKM_DATA_OVERRUN    (0x02)
#define AKM_OVERFLOW        (0x80)
#define AKM_DATA_ERROR      (0x40)

#define AKM_BIT_SELF_TEST   (0x40)

#define AKM_POWER_DOWN          (0x00 | SUPPORTS_AK89xx_HIGH_SENS)
#define AKM_SINGLE_MEASUREMENT  (0x01 | SUPPORTS_AK89xx_HIGH_SENS)
#define AKM_FUSE_ROM_ACCESS     (0x0F | SUPPORTS_AK89xx_HIGH_SENS)
#define AKM_MODE_SELF_TEST      (0x08 | SUPPORTS_AK89xx_HIGH_SENS)

#define AKM_WHOAMI      (0x48)
#endif

#if defined MPU6050
//const struct gyro_reg_s reg = {
//    .who_am_i       = 0x75,
//    .rate_div       = 0x19,
//    .lpf            = 0x1A,
//    .prod_id        = 0x0C,
//    .user_ctrl      = 0x6A,
//    .fifo_en        = 0x23,
//    .gyro_cfg       = 0x1B,
//    .accel_cfg      = 0x1C,
//    .motion_thr     = 0x1F,
//    .motion_dur     = 0x20,
//    .fifo_count_h   = 0x72,
//    .fifo_r_w       = 0x74,
//    .raw_gyro       = 0x43,
//    .raw_accel      = 0x3B,
//    .temp           = 0x41,
//    .int_enable     = 0x38,
//    .dmp_int_status = 0x39,
//    .int_status     = 0x3A,
//    .pwr_mgmt_1     = 0x6B,
//    .pwr_mgmt_2     = 0x6C,
//    .int_pin_cfg    = 0x37,
//    .mem_r_w        = 0x6F,
//    .accel_offs     = 0x06,
//    .i2c_mst        = 0x24,
//    .bank_sel       = 0x6D,
//    .mem_start_addr = 0x6E,
//    .prgm_start_h   = 0x70
//#ifdef AK89xx_SECONDARY
//    ,.raw_compass   = 0x49,
//    .yg_offs_tc     = 0x01,
//    .s0_addr        = 0x25,
//    .s0_reg         = 0x26,
//    .s0_ctrl        = 0x27,
//    .s1_addr        = 0x28,
//    .s1_reg         = 0x29,
//    .s1_ctrl        = 0x2A,
//    .s4_ctrl        = 0x34,
//    .s0_do          = 0x63,
//    .s1_do          = 0x64,
//    .i2c_delay_ctrl = 0x67
//#endif
//};
const struct gyro_reg_s reg = {
0x75,  //who_am_i
0x19,  //rate_div
0x1A,  //lpf
0x0C,  //prod_id
0x6A,  //user_ctrl
0x23,  //fifo_en
0x1B,  //gyro_cfg
0x1C,  //accel_cfg
0x1F,  // motion_thr
0x20,  // motion_dur
0x72,  // fifo_count_h
0x74,  // fifo_r_w
0x43,  // raw_gyro
0x3B,  // raw_accel
0x41,  // temp
0x38,  // int_enable
0x39,  //  dmp_int_status
0x3A,  //  int_status
0x6B,  // pwr_mgmt_1
0x6C,  // pwr_mgmt_2
0x37,  // int_pin_cfg
0x6F,  // mem_r_w
0x06,  // accel_offs
0x24,  // i2c_mst
0x6D,  // bank_sel
0x6E,  // mem_start_addr
0x70   // prgm_start_h
};

//const struct hw_s hw = {
//    .addr           = 0x68,
//    .max_fifo       = 1024,
//    .num_reg        = 118,
//    .temp_sens      = 340,
//    .temp_offset    = -521,
//    .bank_size      = 256
//#if defined AK89xx_SECONDARY
//    ,.compass_fsr    = AK89xx_FSR
//#endif
//};
const struct hw_s hw={
  0x68,  //addr
  1024,  //max_fifo
  118,   //num_reg
  340,   //temp_sens
  -521,  //temp_offset
  256    //bank_size
};

//const struct test_s test = {
//    .gyro_sens      = 32768/250,
//    .accel_sens     = 32768/16,
//    .reg_rate_div   = 0,    /* 1kHz. */
//    .reg_lpf        = 1,    /* 188Hz. */
//    .reg_gyro_fsr   = 0,    /* 250dps. */
//    .reg_accel_fsr  = 0x18, /* 16g. */
//    .wait_ms        = 50,
//    .packet_thresh  = 5,    /* 5% */
//    .min_dps        = 10.f,
//    .max_dps        = 105.f,
//    .max_gyro_var   = 0.14f,
//    .min_g          = 0.3f,
//    .max_g          = 0.95f,
//    .max_accel_var  = 0.14f
//};
const struct test_s test={
32768/250,       //gyro_sens
32768/16,        // accel_sens
0,               // reg_rate_div
1,              //  reg_lpf
0,               // reg_gyro_fsr
0x18,           //  reg_accel_fsr
50,             //  wait_ms
5,              //  packet_thresh
10.0f,           // min_dps
105.0f,          // max_dps
0.14f,          //  max_gyro_var
0.3f,          //   min_g
0.95f,         //   max_g
0.14f          //   max_accel_var
};

//static struct gyro_state_s st = {
//    .reg = &reg,
//    .hw = &hw,
//    .test = &test
//};
static struct gyro_state_s st={
  &reg,
  &hw,
  {0},
  &test
};


#elif defined MPU6500
const struct gyro_reg_s reg = {
    .who_am_i       = 0x75,
    .rate_div       = 0x19,
    .lpf            = 0x1A,
    .prod_id        = 0x0C,
    .user_ctrl      = 0x6A,
    .fifo_en        = 0x23,
    .gyro_cfg       = 0x1B,
    .accel_cfg      = 0x1C,
    .accel_cfg2     = 0x1D,
    .lp_accel_odr   = 0x1E,
    .motion_thr     = 0x1F,
    .motion_dur     = 0x20,
    .fifo_count_h   = 0x72,
    .fifo_r_w       = 0x74,
    .raw_gyro       = 0x43,
    .raw_accel      = 0x3B,
    .temp           = 0x41,
    .int_enable     = 0x38,
    .dmp_int_status = 0x39,
    .int_status     = 0x3A,
    .accel_intel    = 0x69,
    .pwr_mgmt_1     = 0x6B,
    .pwr_mgmt_2     = 0x6C,
    .int_pin_cfg    = 0x37,
    .mem_r_w        = 0x6F,
    .accel_offs     = 0x77,
    .i2c_mst        = 0x24,
    .bank_sel       = 0x6D,
    .mem_start_addr = 0x6E,
    .prgm_start_h   = 0x70
#ifdef AK89xx_SECONDARY
    ,.raw_compass   = 0x49,
    .s0_addr        = 0x25,
    .s0_reg         = 0x26,
    .s0_ctrl        = 0x27,
    .s1_addr        = 0x28,
    .s1_reg         = 0x29,
    .s1_ctrl        = 0x2A,
    .s4_ctrl        = 0x34,
    .s0_do          = 0x63,
    .s1_do          = 0x64,
    .i2c_delay_ctrl = 0x67
#endif
};
const struct hw_s hw = {
    .addr           = 0x68,
    .max_fifo       = 1024,
    .num_reg        = 128,
    .temp_sens      = 321,
    .temp_offset    = 0,
    .bank_size      = 256
#if defined AK89xx_SECONDARY
    ,.compass_fsr    = AK89xx_FSR
#endif
};

const struct test_s test = {
    .gyro_sens      = 32768/250,
    .accel_sens     = 32768/16,
    .reg_rate_div   = 0,    /* 1kHz. */
    .reg_lpf        = 1,    /* 188Hz. */
    .reg_gyro_fsr   = 0,    /* 250dps. */
    .reg_accel_fsr  = 0x18, /* 16g. */
    .wait_ms        = 50,
    .packet_thresh  = 5,    /* 5% */
    .min_dps        = 10.f,
    .max_dps        = 105.f,
    .max_gyro_var   = 0.14f,
    .min_g          = 0.3f,
    .max_g          = 0.95f,
    .max_accel_var  = 0.14f
};

static struct gyro_state_s st = {
    .reg = &reg,
    .hw = &hw,
    .test = &test
};
#endif

#define MAX_PACKET_LENGTH (12)

#ifdef AK89xx_SECONDARY
static int setup_compass(void);
#define MAX_COMPASS_SAMPLE_RATE (100)
#endif

/**
 *  @brief      Enable/disable data ready interrupt.
 *  If the DMP is on, the DMP interrupt is enabled. Otherwise, the data ready
 *  interrupt is used.
 *  @param[in]  enable      1 to enable interrupt.
 *  @return     0 if successful.
 */
static int set_int_enable(unsigned char enable)
{
    unsigned char tmp;

    if (st.chip_cfg.dmp_on) {
        if (enable)
            tmp = BIT_DMP_INT_EN;
        else
            tmp = 0x00;
        if (i2c_write(st.hw->addr, st.reg->int_enable, 1, &tmp))
            return -1;
        st.chip_cfg.int_enable = tmp;
    } else {
        if (!st.chip_cfg.sensors)
            return -1;
        if (enable && st.chip_cfg.int_enable)
            return 0;
        if (enable)
            tmp = BIT_DATA_RDY_EN;
        else
            tmp = 0x00;
        if (i2c_write(st.hw->addr, st.reg->int_enable, 1, &tmp))
            return -1;
        st.chip_cfg.int_enable = tmp;
    }
    return 0;
}

/**
 *  @brief      Register dump for testing.
 *  @return     0 if successful.
 */
int mpu_reg_dump(void)
{
    unsigned char ii;
    unsigned char data;

    for (ii = 0; ii < st.hw->num_reg; ii++) {
        if (ii == st.reg->fifo_r_w || ii == st.reg->mem_r_w)
            continue;
        if (i2c_read(st.hw->addr, ii, 1, &data))
            return -1;
        //("%#5x: %#5x\r\n", ii, data);
    }
    return 0;
}

/**
 *  @brief      Read from a single register.
 *  NOTE: The memory and FIFO read/write registers cannot be accessed.
 *  @param[in]  reg     Register address.
 *  @param[out] data    Register data.
 *  @return     0 if successful.
 */
int mpu_read_reg(unsigned char reg, unsigned char *data)
{
    if (reg == st.reg->fifo_r_w || reg == st.reg->mem_r_w)
        return -1;
    if (reg >= st.hw->num_reg)
        return -1;
    return i2c_read(st.hw->addr, reg, 1, data);
}

/**
 *  @brief      Initialize hardware.
 *  Initial configuration:\n
 *  Gyro FSR: +/- 2000DPS\n
 *  Accel FSR +/- 2G\n
 *  DLPF: 42Hz\n
 *  FIFO rate: 50Hz\n
 *  Clock source: Gyro PLL\n
 *  FIFO: Disabled.\n
 *  Data ready interrupt: Disabled, active low, unlatched.
 *  @param[in]  int_param   Platform-specific parameters to interrupt API.
 *  @return     0 if successful.
 */
int mpu_init(void)
{
    unsigned char data[6], rev;

    /* Reset device. */
    data[0] = BIT_RESET;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 1, data))
        return -1;
    delay_ms(100);

    /* Wake up chip. */
    data[0] = 0x00;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 1, data))
        return -1;

#if defined MPU6050
    /* Check product revision. */
    if (i2c_read(st.hw->addr, st.reg->accel_offs, 6, data))
        return -1;
    rev = ((data[5] & 0x01) << 2) | ((data[3] & 0x01) << 1) |
        (data[1] & 0x01);

    if (rev) {
        /* Congrats, these parts are better. */
        if (rev == 1)
            st.chip_cfg.accel_half = 1;
        else if (rev == 2)
            st.chip_cfg.accel_half = 0;
        else {
            //("Unsupported software product rev %d.\n", rev);
            return -1;
        }
    } else {
        if (i2c_read(st.hw->addr, st.reg->prod_id, 1, data))
            return -1;
        rev = data[0] & 0x0F;
        if (!rev) {
            //("Product ID read as 0 indicates device is either "
                //"incompatible or an MPU3050.\n");
            return -1;
        } else if (rev == 4) {
            //("Half sensitivity part found.\n");
            st.chip_cfg.accel_half = 1;
        } else
            st.chip_cfg.accel_half = 0;
    }
#elif defined MPU6500
#define MPU6500_MEM_REV_ADDR    (0x17)
    if (mpu_read_mem(MPU6500_MEM_REV_ADDR, 1, &rev))
        return -1;
    if (rev == 0x1)
        st.chip_cfg.accel_half = 0;
    else {
        //("Unsupported software product rev %d.\n", rev);
        return -1;
    }

    /* MPU6500 shares 4kB of memory between the DMP and the FIFO. Since the
     * first 3kB are needed by the DMP, we'll use the last 1kB for the FIFO.
     */
    data[0] = BIT_FIFO_SIZE_1024 | 0x8;
    if (i2c_write(st.hw->addr, st.reg->accel_cfg2, 1, data))
        return -1;
#endif

    /* Set to invalid values to ensure no I2C writes are skipped. */
    st.chip_cfg.sensors = 0xFF;
    st.chip_cfg.gyro_fsr = 0xFF;
    st.chip_cfg.accel_fsr = 0xFF;
    st.chip_cfg.lpf = 0xFF;
    st.chip_cfg.sample_rate = 0xFFFF;
    st.chip_cfg.fifo_enable = 0xFF;
    st.chip_cfg.bypass_mode = 0xFF;
#ifdef AK89xx_SECONDARY
    st.chip_cfg.compass_sample_rate = 0xFFFF;
#endif
    /* mpu_set_sensors always preserves this setting. */
    st.chip_cfg.clk_src = INV_CLK_PLL;
    /* Handled in next call to mpu_set_bypass. */
    st.chip_cfg.active_low_int = 1;
    st.chip_cfg.latched_int = 0;
    st.chip_cfg.int_motion_only = 0;
    st.chip_cfg.lp_accel_mode = 0;
    memset(&st.chip_cfg.cache, 0, sizeof(st.chip_cfg.cache));
    st.chip_cfg.dmp_on = 0;
    st.chip_cfg.dmp_loaded = 0;
    st.chip_cfg.dmp_sample_rate = 0;

    if (mpu_set_gyro_fsr(2000))
        return -1;
    if (mpu_set_accel_fsr(2))
        return -1;
    if (mpu_set_lpf(42))
        return -1;
    if (mpu_set_sample_rate(50))
        return -1;
    if (mpu_configure_fifo(0))
        return -1;

//    if (int_param)
//        reg_int_cb(int_param);

#ifdef AK89xx_SECONDARY
    setup_compass();
    if (mpu_set_compass_sample_rate(10))
        return -1;
#else
    /* Already disabled by setup_compass. */
    if (mpu_set_bypass(0))
        return -1;
#endif

    mpu_set_sensors(0);
    return 0;
}

/**
 *  @brief      Enter low-power accel-only mode.
 *  In low-power accel mode, the chip goes to sleep and only wakes up to sample
 *  the accelerometer at one of the following frequencies:
 *  \n MPU6050: 1.25Hz, 5Hz, 20Hz, 40Hz
 *  \n MPU6500: 1.25Hz, 2.5Hz, 5Hz, 10Hz, 20Hz, 40Hz, 80Hz, 160Hz, 320Hz, 640Hz
 *  \n If the requested rate is not one listed above, the device will be set to
 *  the next highest rate. Requesting a rate above the maximum supported
 *  frequency will result in an error.
 *  \n To select a fractional wake-up frequency, round down the value passed to
 *  @e rate.
 *  @param[in]  rate        Minimum sampling rate, or zero to disable LP
 *                          accel mode.
 *  @return     0 if successful.
 */
int mpu_lp_accel_mode(unsigned char rate)
{
    unsigned char tmp[2];

    if (rate > 40)
        return -1;

    if (!rate) {
        mpu_set_int_latched(0);
        tmp[0] = 0;
        tmp[1] = BIT_STBY_XYZG;
        if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 2, tmp))
            return -1;
        st.chip_cfg.lp_accel_mode = 0;
        return 0;
    }
    /* For LP accel, we automatically configure the hardware to produce latched
     * interrupts. In LP accel mode, the hardware cycles into sleep mode before
     * it gets a chance to deassert the interrupt pin; therefore, we shift this
     * responsibility over to the MCU.
     *
     * Any register read will clear the interrupt.
     */
    mpu_set_int_latched(1);
#if defined MPU6050
    tmp[0] = BIT_LPA_CYCLE;
    if (rate == 1) {
        tmp[1] = INV_LPA_1_25HZ;
        mpu_set_lpf(5);
    } else if (rate <= 5) {
        tmp[1] = INV_LPA_5HZ;
        mpu_set_lpf(5);
    } else if (rate <= 20) {
        tmp[1] = INV_LPA_20HZ;
        mpu_set_lpf(10);
    } else {
        tmp[1] = INV_LPA_40HZ;
        mpu_set_lpf(20);
    }
    tmp[1] = (tmp[1] << 6) | BIT_STBY_XYZG;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 2, tmp))
        return -1;
#elif defined MPU6500
    /* Set wake frequency. */
    if (rate == 1)
        tmp[0] = INV_LPA_1_25HZ;
    else if (rate == 2)
        tmp[0] = INV_LPA_2_5HZ;
    else if (rate <= 5)
        tmp[0] = INV_LPA_5HZ;
    else if (rate <= 10)
        tmp[0] = INV_LPA_10HZ;
    else if (rate <= 20)
        tmp[0] = INV_LPA_20HZ;
    else if (rate <= 40)
        tmp[0] = INV_LPA_40HZ;
    else if (rate <= 80)
        tmp[0] = INV_LPA_80HZ;
    else if (rate <= 160)
        tmp[0] = INV_LPA_160HZ;
    else if (rate <= 320)
        tmp[0] = INV_LPA_320HZ;
    else
        tmp[0] = INV_LPA_640HZ;
    if (i2c_write(st.hw->addr, st.reg->lp_accel_odr, 1, tmp))
        return -1;
    tmp[0] = BIT_LPA_CYCLE;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 1, tmp))
        return -1;
#endif
    st.chip_cfg.sensors = INV_XYZ_ACCEL;
    st.chip_cfg.clk_src = 0;
    st.chip_cfg.lp_accel_mode = 1;
    mpu_configure_fifo(0);

    return 0;
}

/**
 *  @brief      Read raw gyro data directly from the registers.
 *  @param[out] data        Raw data in hardware units.
 *  @param[out] timestamp   Timestamp in milliseconds. Null if not needed.
 *  @return     0 if successful.
 */
int mpu_get_gyro_reg(short *data, unsigned long *timestamp)
{
    unsigned char tmp[6];

    if (!(st.chip_cfg.sensors & INV_XYZ_GYRO))
        return -1;

    if (i2c_read(st.hw->addr, st.reg->raw_gyro, 6, tmp))
        return -1;
    data[0] = (tmp[0] << 8) | tmp[1];
    data[1] = (tmp[2] << 8) | tmp[3];
    data[2] = (tmp[4] << 8) | tmp[5];
    if (timestamp)
        get_ms(timestamp);
    return 0;
}

/**
 *  @brief      Read raw accel data directly from the registers.
 *  @param[out] data        Raw data in hardware units.
 *  @param[out] timestamp   Timestamp in milliseconds. Null if not needed.
 *  @return     0 if successful.
 */
int mpu_get_accel_reg(short *data, unsigned long *timestamp)
{
    unsigned char tmp[6];

    if (!(st.chip_cfg.sensors & INV_XYZ_ACCEL))
        return -1;

    if (i2c_read(st.hw->addr, st.reg->raw_accel, 6, tmp))
        return -1;
    data[0] = (tmp[0] << 8) | tmp[1];
    data[1] = (tmp[2] << 8) | tmp[3];
    data[2] = (tmp[4] << 8) | tmp[5];
    if (timestamp)
        get_ms(timestamp);
    return 0;
}

/**
 *  @brief      Read temperature data directly from the registers.
 *  @param[out] data        Data in q16 format.
 *  @param[out] timestamp   Timestamp in milliseconds. Null if not needed.
 *  @return     0 if successful.
 */
int mpu_get_temperature(long *data, unsigned long *timestamp)
{
    unsigned char tmp[2];
    short raw;

    if (!(st.chip_cfg.sensors))
        return -1;

    if (i2c_read(st.hw->addr, st.reg->temp, 2, tmp))
        return -1;
    raw = (tmp[0] << 8) | tmp[1];
    if (timestamp)
        get_ms(timestamp);

    data[0] = (long)((35 + ((raw - (float)st.hw->temp_offset) / st.hw->temp_sens)) * 65536L);
    return 0;
}

/**
 *  @brief      Push biases to the accel bias registers.
 *  This function expects biases relative to the current sensor output, and
 *  these biases will be added to the factory-supplied values.
 *  @param[in]  accel_bias  New biases.
 *  @return     0 if successful.
 */
int mpu_set_accel_bias(const long *accel_bias)
{
    unsigned char data[6];
    short accel_hw[3];
    short got_accel[3];
    short fg[3];

    if (!accel_bias)
        return -1;
    if (!accel_bias[0] && !accel_bias[1] && !accel_bias[2])
        return 0;

    if (i2c_read(st.hw->addr, 3, 3, data))
        return -1;
    fg[0] = ((data[0] >> 4) + 8) & 0xf;
    fg[1] = ((data[1] >> 4) + 8) & 0xf;
    fg[2] = ((data[2] >> 4) + 8) & 0xf;

    accel_hw[0] = (short)(accel_bias[0] * 2 / (64 + fg[0]));
    accel_hw[1] = (short)(accel_bias[1] * 2 / (64 + fg[1]));
    accel_hw[2] = (short)(accel_bias[2] * 2 / (64 + fg[2]));

    if (i2c_read(st.hw->addr, 0x06, 6, data))
        return -1;

    got_accel[0] = ((short)data[0] << 8) | data[1];
    got_accel[1] = ((short)data[2] << 8) | data[3];
    got_accel[2] = ((short)data[4] << 8) | data[5];

    accel_hw[0] += got_accel[0];
    accel_hw[1] += got_accel[1];
    accel_hw[2] += got_accel[2];

    data[0] = (accel_hw[0] >> 8) & 0xff;
    data[1] = (accel_hw[0]) & 0xff;
    data[2] = (accel_hw[1] >> 8) & 0xff;
    data[3] = (accel_hw[1]) & 0xff;
    data[4] = (accel_hw[2] >> 8) & 0xff;
    data[5] = (accel_hw[2]) & 0xff;

    if (i2c_write(st.hw->addr, 0x06, 6, data))
        return -1;
    return 0;
}

/**
 *  @brief  Reset FIFO read/write pointers.
 *  @return 0 if successful.
 */
int mpu_reset_fifo(void)
{
    unsigned char data;

    if (!(st.chip_cfg.sensors))
        return -1;

    data = 0;
    if (i2c_write(st.hw->addr, st.reg->int_enable, 1, &data))
        return -1;
    if (i2c_write(st.hw->addr, st.reg->fifo_en, 1, &data))
        return -1;
    if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &data))
        return -1;

    if (st.chip_cfg.dmp_on) {
        data = BIT_FIFO_RST | BIT_DMP_RST;
        if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &data))
            return -1;
        delay_ms(50);
        data = BIT_DMP_EN | BIT_FIFO_EN;
        if (st.chip_cfg.sensors & INV_XYZ_COMPASS)
            data |= BIT_AUX_IF_EN;
        if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &data))
            return -1;
        if (st.chip_cfg.int_enable)
            data = BIT_DMP_INT_EN;
        else
            data = 0;
        if (i2c_write(st.hw->addr, st.reg->int_enable, 1, &data))
            return -1;
        data = 0;
        if (i2c_write(st.hw->addr, st.reg->fifo_en, 1, &data))
            return -1;
    } else {
        data = BIT_FIFO_RST;
        if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &data))
            return -1;
        if (st.chip_cfg.bypass_mode || !(st.chip_cfg.sensors & INV_XYZ_COMPASS))
            data = BIT_FIFO_EN;
        else
            data = BIT_FIFO_EN | BIT_AUX_IF_EN;
        if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &data))
            return -1;
        delay_ms(50);
        if (st.chip_cfg.int_enable)
            data = BIT_DATA_RDY_EN;
        else
            data = 0;
        if (i2c_write(st.hw->addr, st.reg->int_enable, 1, &data))
            return -1;
        if (i2c_write(st.hw->addr, st.reg->fifo_en, 1, &st.chip_cfg.fifo_enable))
            return -1;
    }
    return 0;
}

/**
 *  @brief      Get the gyro full-scale range.
 *  @param[out] fsr Current full-scale range.
 *  @return     0 if successful.
 */
int mpu_get_gyro_fsr(unsigned short *fsr)
{
    switch (st.chip_cfg.gyro_fsr) {
    case INV_FSR_250DPS:
        fsr[0] = 250;
        break;
    case INV_FSR_500DPS:
        fsr[0] = 500;
        break;
    case INV_FSR_1000DPS:
        fsr[0] = 1000;
        break;
    case INV_FSR_2000DPS:
        fsr[0] = 2000;
        break;
    default:
        fsr[0] = 0;
        break;
    }
    return 0;
}

/**
 *  @brief      Set the gyro full-scale range.
 *  @param[in]  fsr Desired full-scale range.
 *  @return     0 if successful.
 */
int mpu_set_gyro_fsr(unsigned short fsr)
{
    unsigned char data;

    if (!(st.chip_cfg.sensors))
        return -1;

    switch (fsr) {
    case 250:
        data = INV_FSR_250DPS << 3;
        break;
    case 500:
        data = INV_FSR_500DPS << 3;
        break;
    case 1000:
        data = INV_FSR_1000DPS << 3;
        break;
    case 2000:
        data = INV_FSR_2000DPS << 3;
        break;
    default:
        return -1;
    }

    if (st.chip_cfg.gyro_fsr == (data >> 3))
        return 0;
    if (i2c_write(st.hw->addr, st.reg->gyro_cfg, 1, &data))
        return -1;
    st.chip_cfg.gyro_fsr = data >> 3;
    return 0;
}

/**
 *  @brief      Get the accel full-scale range.
 *  @param[out] fsr Current full-scale range.
 *  @return     0 if successful.
 */
int mpu_get_accel_fsr(unsigned char *fsr)
{
    switch (st.chip_cfg.accel_fsr) {
    case INV_FSR_2G:
        fsr[0] = 2;
        break;
    case INV_FSR_4G:
        fsr[0] = 4;
        break;
    case INV_FSR_8G:
        fsr[0] = 8;
        break;
    case INV_FSR_16G:
        fsr[0] = 16;
        break;
    default:
        return -1;
    }
    if (st.chip_cfg.accel_half)
        fsr[0] <<= 1;
    return 0;
}

/**
 *  @brief      Set the accel full-scale range.
 *  @param[in]  fsr Desired full-scale range.
 *  @return     0 if successful.
 */
int mpu_set_accel_fsr(unsigned char fsr)
{
    unsigned char data;

    if (!(st.chip_cfg.sensors))
        return -1;

    switch (fsr) {
    case 2:
        data = INV_FSR_2G << 3;
        break;
    case 4:
        data = INV_FSR_4G << 3;
        break;
    case 8:
        data = INV_FSR_8G << 3;
        break;
    case 16:
        data = INV_FSR_16G << 3;
        break;
    default:
        return -1;
    }

    if (st.chip_cfg.accel_fsr == (data >> 3))
        return 0;
    if (i2c_write(st.hw->addr, st.reg->accel_cfg, 1, &data))
        return -1;
    st.chip_cfg.accel_fsr = data >> 3;
    return 0;
}

/**
 *  @brief      Get the current DLPF setting.
 *  @param[out] lpf Current LPF setting.
 *  0 if successful.
 */
int mpu_get_lpf(unsigned short *lpf)
{
    switch (st.chip_cfg.lpf) {
    case INV_FILTER_188HZ:
        lpf[0] = 188;
        break;
    case INV_FILTER_98HZ:
        lpf[0] = 98;
        break;
    case INV_FILTER_42HZ:
        lpf[0] = 42;
        break;
    case INV_FILTER_20HZ:
        lpf[0] = 20;
        break;
    case INV_FILTER_10HZ:
        lpf[0] = 10;
        break;
    case INV_FILTER_5HZ:
        lpf[0] = 5;
        break;
    case INV_FILTER_256HZ_NOLPF2:
    case INV_FILTER_2100HZ_NOLPF:
    default:
        lpf[0] = 0;
        break;
    }
    return 0;
}

/**
 *  @brief      Set digital low pass filter.
 *  The following LPF settings are supported: 188, 98, 42, 20, 10, 5.
 *  @param[in]  lpf Desired LPF setting.
 *  @return     0 if successful.
 */
int mpu_set_lpf(unsigned short lpf)
{
    unsigned char data;

    if (!(st.chip_cfg.sensors))
        return -1;

    if (lpf >= 188)
        data = INV_FILTER_188HZ;
    else if (lpf >= 98)
        data = INV_FILTER_98HZ;
    else if (lpf >= 42)
        data = INV_FILTER_42HZ;
    else if (lpf >= 20)
        data = INV_FILTER_20HZ;
    else if (lpf >= 10)
        data = INV_FILTER_10HZ;
    else
        data = INV_FILTER_5HZ;

    if (st.chip_cfg.lpf == data)
        return 0;
    if (i2c_write(st.hw->addr, st.reg->lpf, 1, &data))
        return -1;
    st.chip_cfg.lpf = data;
    return 0;
}

/**
 *  @brief      Get sampling rate.
 *  @param[out] rate    Current sampling rate (Hz).
 *  @return     0 if successful.
 */
int mpu_get_sample_rate(unsigned short *rate)
{
    if (st.chip_cfg.dmp_on)
        return -1;
    else
        rate[0] = st.chip_cfg.sample_rate;
    return 0;
}

/**
 *  @brief      Set sampling rate.
 *  Sampling rate must be between 4Hz and 1kHz.
 *  @param[in]  rate    Desired sampling rate (Hz).
 *  @return     0 if successful.
 */
int mpu_set_sample_rate(unsigned short rate)
{
    unsigned char data;

    if (!(st.chip_cfg.sensors))
        return -1;

    if (st.chip_cfg.dmp_on)
        return -1;
    else {
        if (st.chip_cfg.lp_accel_mode) {
            if (rate && (rate <= 40)) {
                /* Just stay in low-power accel mode. */
                mpu_lp_accel_mode(rate);
                return 0;
            }
            /* Requested rate exceeds the allowed frequencies in LP accel mode,
             * switch back to full-power mode.
             */
            mpu_lp_accel_mode(0);
        }
        if (rate < 4)
            rate = 4;
        else if (rate > 1000)
            rate = 1000;

        data = 1000 / rate - 1;
        if (i2c_write(st.hw->addr, st.reg->rate_div, 1, &data))
            return -1;

        st.chip_cfg.sample_rate = 1000 / (1 + data);

#ifdef AK89xx_SECONDARY
        mpu_set_compass_sample_rate(min(st.chip_cfg.compass_sample_rate, MAX_COMPASS_SAMPLE_RATE));
#endif

        /* Automatically set LPF to 1/2 sampling rate. */
        mpu_set_lpf(st.chip_cfg.sample_rate >> 1);
        return 0;
    }
}

/**
 *  @brief      Get compass sampling rate.
 *  @param[out] rate    Current compass sampling rate (Hz).
 *  @return     0 if successful.
 */
int mpu_get_compass_sample_rate(unsigned short *rate)
{
#ifdef AK89xx_SECONDARY
    rate[0] = st.chip_cfg.compass_sample_rate;
    return 0;
#else
    rate[0] = 0;
    return -1;
#endif
}

/**
 *  @brief      Set compass sampling rate.
 *  The compass on the auxiliary I2C bus is read by the MPU hardware at a
 *  maximum of 100Hz. The actual rate can be set to a fraction of the gyro
 *  sampling rate.
 *
 *  \n WARNING: The new rate may be different than what was requested. Call
 *  mpu_get_compass_sample_rate to check the actual setting.
 *  @param[in]  rate    Desired compass sampling rate (Hz).
 *  @return     0 if successful.
 */
int mpu_set_compass_sample_rate(unsigned short rate)
{
#ifdef AK89xx_SECONDARY
    unsigned char div;
    if (!rate || rate > st.chip_cfg.sample_rate || rate > MAX_COMPASS_SAMPLE_RATE)
        return -1;

    div = st.chip_cfg.sample_rate / rate - 1;
    if (i2c_write(st.hw->addr, st.reg->s4_ctrl, 1, &div))
        return -1;
    st.chip_cfg.compass_sample_rate = st.chip_cfg.sample_rate / (div + 1);
    return 0;
#else
    return -1;
#endif
}

/**
 *  @brief      Get gyro sensitivity scale factor.
 *  @param[out] sens    Conversion from hardware units to dps.
 *  @return     0 if successful.
 */
int mpu_get_gyro_sens(float *sens)
{
    switch (st.chip_cfg.gyro_fsr) {
    case INV_FSR_250DPS:
        sens[0] = 131.f;
        break;
    case INV_FSR_500DPS:
        sens[0] = 65.5f;
        break;
    case INV_FSR_1000DPS:
        sens[0] = 32.8f;
        break;
    case INV_FSR_2000DPS:
        sens[0] = 16.4f;
        break;
    default:
        return -1;
    }
    return 0;
}

/**
 *  @brief      Get accel sensitivity scale factor.
 *  @param[out] sens    Conversion from hardware units to g's.
 *  @return     0 if successful.
 */
int mpu_get_accel_sens(unsigned short *sens)
{
    switch (st.chip_cfg.accel_fsr) {
    case INV_FSR_2G:
        sens[0] = 16384;
        break;
    case INV_FSR_4G:
        sens[0] = 8092;
        break;
    case INV_FSR_8G:
        sens[0] = 4096;
        break;
    case INV_FSR_16G:
        sens[0] = 2048;
        break;
    default:
        return -1;
    }
    if (st.chip_cfg.accel_half)
        sens[0] >>= 1;
    return 0;
}

/**
 *  @brief      Get current FIFO configuration.
 *  @e sensors can contain a combination of the following flags:
 *  \n INV_X_GYRO, INV_Y_GYRO, INV_Z_GYRO
 *  \n INV_XYZ_GYRO
 *  \n INV_XYZ_ACCEL
 *  @param[out] sensors Mask of sensors in FIFO.
 *  @return     0 if successful.
 */
int mpu_get_fifo_config(unsigned char *sensors)
{
    sensors[0] = st.chip_cfg.fifo_enable;
    return 0;
}

/**
 *  @brief      Select which sensors are pushed to FIFO.
 *  @e sensors can contain a combination of the following flags:
 *  \n INV_X_GYRO, INV_Y_GYRO, INV_Z_GYRO
 *  \n INV_XYZ_GYRO
 *  \n INV_XYZ_ACCEL
 *  @param[in]  sensors Mask of sensors to push to FIFO.
 *  @return     0 if successful.
 */
int mpu_configure_fifo(unsigned char sensors)
{
    unsigned char prev;
    int result = 0;

    /* Compass data isn't going into the FIFO. Stop trying. */
    sensors &= ~INV_XYZ_COMPASS;

    if (st.chip_cfg.dmp_on)
        return 0;
    else {
        if (!(st.chip_cfg.sensors))
            return -1;
        prev = st.chip_cfg.fifo_enable;
        st.chip_cfg.fifo_enable = sensors & st.chip_cfg.sensors;
        if (st.chip_cfg.fifo_enable != sensors)
            /* You're not getting what you asked for. Some sensors are
             * asleep.
             */
            result = -1;
        else
            result = 0;
        if (sensors || st.chip_cfg.lp_accel_mode)
            set_int_enable(1);
        else
            set_int_enable(0);
        if (sensors) {
            if (mpu_reset_fifo()) {
                st.chip_cfg.fifo_enable = prev;
                return -1;
            }
        }
    }

    return result;
}

/**
 *  @brief      Get current power state.
 *  @param[in]  power_on    1 if turned on, 0 if suspended.
 *  @return     0 if successful.
 */
int mpu_get_power_state(unsigned char *power_on)
{
    if (st.chip_cfg.sensors)
        power_on[0] = 1;
    else
        power_on[0] = 0;
    return 0;
}

/**
 *  @brief      Turn specific sensors on/off.
 *  @e sensors can contain a combination of the following flags:
 *  \n INV_X_GYRO, INV_Y_GYRO, INV_Z_GYRO
 *  \n INV_XYZ_GYRO
 *  \n INV_XYZ_ACCEL
 *  \n INV_XYZ_COMPASS
 *  @param[in]  sensors    Mask of sensors to wake.
 *  @return     0 if successful.
 */
int mpu_set_sensors(unsigned char sensors)
{
    unsigned char data;
#ifdef AK89xx_SECONDARY
    unsigned char user_ctrl;
#endif

    if (sensors & INV_XYZ_GYRO)
        data = INV_CLK_PLL;
    else if (sensors)
        data = 0;
    else
        data = BIT_SLEEP;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 1, &data)) {
        st.chip_cfg.sensors = 0;
        return -1;
    }
    st.chip_cfg.clk_src = data & ~BIT_SLEEP;

    data = 0;
    if (!(sensors & INV_X_GYRO))
        data |= BIT_STBY_XG;
    if (!(sensors & INV_Y_GYRO))
        data |= BIT_STBY_YG;
    if (!(sensors & INV_Z_GYRO))
        data |= BIT_STBY_ZG;
    if (!(sensors & INV_XYZ_ACCEL))
        data |= BIT_STBY_XYZA;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_2, 1, &data)) {
        st.chip_cfg.sensors = 0;
        return -1;
    }

    if (sensors && (sensors != INV_XYZ_ACCEL))
        /* Latched interrupts only used in LP accel mode. */
        mpu_set_int_latched(0);

#ifdef AK89xx_SECONDARY
#ifdef AK89xx_BYPASS
    if (sensors & INV_XYZ_COMPASS)
        mpu_set_bypass(1);
    else
        mpu_set_bypass(0);
#else
    if (i2c_read(st.hw->addr, st.reg->user_ctrl, 1, &user_ctrl))
        return -1;
    /* Handle AKM power management. */
    if (sensors & INV_XYZ_COMPASS) {
        data = AKM_SINGLE_MEASUREMENT;
        user_ctrl |= BIT_AUX_IF_EN;
    } else {
        data = AKM_POWER_DOWN;
        user_ctrl &= ~BIT_AUX_IF_EN;
    }
    if (st.chip_cfg.dmp_on)
        user_ctrl |= BIT_DMP_EN;
    else
        user_ctrl &= ~BIT_DMP_EN;
    if (i2c_write(st.hw->addr, st.reg->s1_do, 1, &data))
        return -1;
    /* Enable/disable I2C master mode. */
    if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &user_ctrl))
        return -1;
#endif
#endif

    st.chip_cfg.sensors = sensors;
    st.chip_cfg.lp_accel_mode = 0;
    delay_ms(50);
    return 0;
}

/**
 *  @brief      Read the MPU interrupt status registers.
 *  @param[out] status  Mask of interrupt bits.
 *  @return     0 if successful.
 */
int mpu_get_int_status(short *status)
{
    unsigned char tmp[2];
    if (!st.chip_cfg.sensors)
        return -1;
    if (i2c_read(st.hw->addr, st.reg->dmp_int_status, 2, tmp))
        return -1;
    status[0] = (tmp[0] << 8) | tmp[1];
    return 0;
}

/**
 *  @brief      Get one packet from the FIFO.
 *  If @e sensors does not contain a particular sensor, disregard the data
 *  returned to that pointer.
 *  \n @e sensors can contain a combination of the following flags:
 *  \n INV_X_GYRO, INV_Y_GYRO, INV_Z_GYRO
 *  \n INV_XYZ_GYRO
 *  \n INV_XYZ_ACCEL
 *  \n If the FIFO has no new data, @e sensors will be zero.
 *  \n If the FIFO is disabled, @e sensors will be zero and this function will
 *  return a non-zero error code.
 *  @param[out] gyro        Gyro data in hardware units.
 *  @param[out] accel       Accel data in hardware units.
 *  @param[out] timestamp   Timestamp in milliseconds.
 *  @param[out] sensors     Mask of sensors read from FIFO.
 *  @param[out] more        Number of remaining packets.
 *  @return     0 if successful.
 */
int mpu_read_fifo(short *gyro, short *accel, unsigned long *timestamp,
        unsigned char *sensors, unsigned char *more)
{
    /* Assumes maximum packet size is gyro (6) + accel (6). */
    unsigned char data[MAX_PACKET_LENGTH];
    unsigned char packet_size = 0;
    unsigned short fifo_count, index = 0;

    if (st.chip_cfg.dmp_on)
        return -1;

    sensors[0] = 0;
    if (!st.chip_cfg.sensors)
        return -1;
    if (!st.chip_cfg.fifo_enable)
        return -1;

    if (st.chip_cfg.fifo_enable & INV_X_GYRO)
        packet_size += 2;
    if (st.chip_cfg.fifo_enable & INV_Y_GYRO)
        packet_size += 2;
    if (st.chip_cfg.fifo_enable & INV_Z_GYRO)
        packet_size += 2;
    if (st.chip_cfg.fifo_enable & INV_XYZ_ACCEL)
        packet_size += 6;

    if (i2c_read(st.hw->addr, st.reg->fifo_count_h, 2, data))
        return -1;
    fifo_count = (data[0] << 8) | data[1];
    if (fifo_count < packet_size)
        return 0;
//    //("FIFO count: %hd\n", fifo_count);
    if (fifo_count > (st.hw->max_fifo >> 1)) {
        /* FIFO is 50% full, better check overflow bit. */
        if (i2c_read(st.hw->addr, st.reg->int_status, 1, data))
            return -1;
        if (data[0] & BIT_FIFO_OVERFLOW) {
            mpu_reset_fifo();
            return -2;
        }
    }
    get_ms((unsigned long*)timestamp);

    if (i2c_read(st.hw->addr, st.reg->fifo_r_w, packet_size, data))
        return -1;
    more[0] = fifo_count / packet_size - 1;
    sensors[0] = 0;

    if ((index != packet_size) && st.chip_cfg.fifo_enable & INV_XYZ_ACCEL) {
        accel[0] = (data[index+0] << 8) | data[index+1];
        accel[1] = (data[index+2] << 8) | data[index+3];
        accel[2] = (data[index+4] << 8) | data[index+5];
        sensors[0] |= INV_XYZ_ACCEL;
        index += 6;
    }
    if ((index != packet_size) && st.chip_cfg.fifo_enable & INV_X_GYRO) {
        gyro[0] = (data[index+0] << 8) | data[index+1];
        sensors[0] |= INV_X_GYRO;
        index += 2;
    }
    if ((index != packet_size) && st.chip_cfg.fifo_enable & INV_Y_GYRO) {
        gyro[1] = (data[index+0] << 8) | data[index+1];
        sensors[0] |= INV_Y_GYRO;
        index += 2;
    }
    if ((index != packet_size) && st.chip_cfg.fifo_enable & INV_Z_GYRO) {
        gyro[2] = (data[index+0] << 8) | data[index+1];
        sensors[0] |= INV_Z_GYRO;
        index += 2;
    }

    return 0;
}

/**
 *  @brief      Get one unparsed packet from the FIFO.
 *  This function should be used if the packet is to be parsed elsewhere.
 *  @param[in]  length  Length of one FIFO packet.
 *  @param[in]  data    FIFO packet.
 *  @param[in]  more    Number of remaining packets.
 */
int mpu_read_fifo_stream(unsigned short length, unsigned char *data,
    unsigned char *more)
{
    unsigned char tmp[2];
    unsigned short fifo_count;
    if (!st.chip_cfg.dmp_on)
        return -1;
    if (!st.chip_cfg.sensors)
        return -1;

    if (i2c_read(st.hw->addr, st.reg->fifo_count_h, 2, tmp))
        return -1;
    fifo_count = (tmp[0] << 8) | tmp[1];
    if (fifo_count < length) {
        more[0] = 0;
        return -1;
    }
    if (fifo_count > (st.hw->max_fifo >> 1)) {
        /* FIFO is 50% full, better check overflow bit. */
        if (i2c_read(st.hw->addr, st.reg->int_status, 1, tmp))
            return -1;
        if (tmp[0] & BIT_FIFO_OVERFLOW) {
            mpu_reset_fifo();
            return -2;
        }
    }

    if (i2c_read(st.hw->addr, st.reg->fifo_r_w, length, data))
        return -1;
    more[0] = fifo_count / length - 1;
    return 0;
}

/**
 *  @brief      Set device to bypass mode.
 *  @param[in]  bypass_on   1 to enable bypass mode.
 *  @return     0 if successful.
 */
int mpu_set_bypass(unsigned char bypass_on)
{
    unsigned char tmp;

    if (st.chip_cfg.bypass_mode == bypass_on)
        return 0;

    if (bypass_on) {
        if (i2c_read(st.hw->addr, st.reg->user_ctrl, 1, &tmp))
            return -1;
        tmp &= ~BIT_AUX_IF_EN;
        if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &tmp))
            return -1;
        delay_ms(3);
        tmp = BIT_BYPASS_EN;
        if (st.chip_cfg.active_low_int)
            tmp |= BIT_ACTL;
        if (st.chip_cfg.latched_int)
            tmp |= BIT_LATCH_EN | BIT_ANY_RD_CLR;
        if (i2c_write(st.hw->addr, st.reg->int_pin_cfg, 1, &tmp))
            return -1;
    } else {
        /* Enable I2C master mode if compass is being used. */
        if (i2c_read(st.hw->addr, st.reg->user_ctrl, 1, &tmp))
            return -1;
        if (st.chip_cfg.sensors & INV_XYZ_COMPASS)
            tmp |= BIT_AUX_IF_EN;
        else
            tmp &= ~BIT_AUX_IF_EN;
        if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, &tmp))
            return -1;
        delay_ms(3);
        if (st.chip_cfg.active_low_int)
            tmp = BIT_ACTL;
        else
            tmp = 0;
        if (st.chip_cfg.latched_int)
            tmp |= BIT_LATCH_EN | BIT_ANY_RD_CLR;
        if (i2c_write(st.hw->addr, st.reg->int_pin_cfg, 1, &tmp))
            return -1;
    }
    st.chip_cfg.bypass_mode = bypass_on;
    return 0;
}

/**
 *  @brief      Set interrupt level.
 *  @param[in]  active_low  1 for active low, 0 for active high.
 *  @return     0 if successful.
 */
int mpu_set_int_level(unsigned char active_low)
{
    st.chip_cfg.active_low_int = active_low;
    return 0;
}

/**
 *  @brief      Enable latched interrupts.
 *  Any MPU register will clear the interrupt.
 *  @param[in]  enable  1 to enable, 0 to disable.
 *  @return     0 if successful.
 */
int mpu_set_int_latched(unsigned char enable)
{
    unsigned char tmp;
    if (st.chip_cfg.latched_int == enable)
        return 0;

    if (enable)
        tmp = BIT_LATCH_EN | BIT_ANY_RD_CLR;
    else
        tmp = 0;
    if (st.chip_cfg.bypass_mode)
        tmp |= BIT_BYPASS_EN;
    if (st.chip_cfg.active_low_int)
        tmp |= BIT_ACTL;
    if (i2c_write(st.hw->addr, st.reg->int_pin_cfg, 1, &tmp))
        return -1;
    st.chip_cfg.latched_int = enable;
    return 0;
}

#ifdef MPU6050
static int get_accel_prod_shift(float *st_shift)
{
    unsigned char tmp[4], shift_code[3], ii;

    if (i2c_read(st.hw->addr, 0x0D, 4, tmp))
        return 0x07;

    shift_code[0] = ((tmp[0] & 0xE0) >> 3) | ((tmp[3] & 0x30) >> 4);
    shift_code[1] = ((tmp[1] & 0xE0) >> 3) | ((tmp[3] & 0x0C) >> 2);
    shift_code[2] = ((tmp[2] & 0xE0) >> 3) | (tmp[3] & 0x03);
    for (ii = 0; ii < 3; ii++) {
        if (!shift_code[ii]) {
            st_shift[ii] = 0.f;
            continue;
        }
        /* Equivalent to..
         * st_shift[ii] = 0.34f * powf(0.92f/0.34f, (shift_code[ii]-1) / 30.f)
         */
        st_shift[ii] = 0.34f;
        while (--shift_code[ii])
            st_shift[ii] *= 1.034f;
    }
    return 0;
}

static int accel_self_test(long *bias_regular, long *bias_st)
{
    int jj, result = 0;
    float st_shift[3], st_shift_cust, st_shift_var;

    get_accel_prod_shift(st_shift);
    for(jj = 0; jj < 3; jj++) {
        st_shift_cust = labs(bias_regular[jj] - bias_st[jj]) / 65536.f;
        if (st_shift[jj]) {
            st_shift_var = st_shift_cust / st_shift[jj] - 1.f;
            if (fabs(st_shift_var) > test.max_accel_var)
                result |= 1 << jj;
        } else if ((st_shift_cust < test.min_g) ||
            (st_shift_cust > test.max_g))
            result |= 1 << jj;
    }

    return result;
}

static int gyro_self_test(long *bias_regular, long *bias_st)
{
    int jj, result = 0;
    unsigned char tmp[3];
    float st_shift, st_shift_cust, st_shift_var;

    if (i2c_read(st.hw->addr, 0x0D, 3, tmp))
        return 0x07;

    tmp[0] &= 0x1F;
    tmp[1] &= 0x1F;
    tmp[2] &= 0x1F;

    for (jj = 0; jj < 3; jj++) {
        st_shift_cust = labs(bias_regular[jj] - bias_st[jj]) / 65536.f;
        if (tmp[jj]) {
            st_shift = 3275.f / test.gyro_sens;
            while (--tmp[jj])
                st_shift *= 1.046f;
            st_shift_var = st_shift_cust / st_shift - 1.f;
            if (fabs(st_shift_var) > test.max_gyro_var)
                result |= 1 << jj;
        } else if ((st_shift_cust < test.min_dps) ||
            (st_shift_cust > test.max_dps))
            result |= 1 << jj;
    }
    return result;
}

#ifdef AK89xx_SECONDARY
static int compass_self_test(void)
{
    unsigned char tmp[6];
    unsigned char tries = 10;
    int result = 0x07;
    short data;

    mpu_set_bypass(1);

    tmp[0] = AKM_POWER_DOWN;
    if (i2c_write(st.chip_cfg.compass_addr, AKM_REG_CNTL, 1, tmp))
        return 0x07;
    tmp[0] = AKM_BIT_SELF_TEST;
    if (i2c_write(st.chip_cfg.compass_addr, AKM_REG_ASTC, 1, tmp))
        goto AKM_restore;
    tmp[0] = AKM_MODE_SELF_TEST;
    if (i2c_write(st.chip_cfg.compass_addr, AKM_REG_CNTL, 1, tmp))
        goto AKM_restore;

    do {
        delay_ms(10);
        if (i2c_read(st.chip_cfg.compass_addr, AKM_REG_ST1, 1, tmp))
            goto AKM_restore;
        if (tmp[0] & AKM_DATA_READY)
            break;
    } while (tries--);
    if (!(tmp[0] & AKM_DATA_READY))
        goto AKM_restore;

    if (i2c_read(st.chip_cfg.compass_addr, AKM_REG_HXL, 6, tmp))
        goto AKM_restore;

    result = 0;
    data = (short)(tmp[1] << 8) | tmp[0];
    if ((data > 100) || (data < -100))
        result |= 0x01;
    data = (short)(tmp[3] << 8) | tmp[2];
    if ((data > 100) || (data < -100))
        result |= 0x02;
    data = (short)(tmp[5] << 8) | tmp[4];
    if ((data > -300) || (data < -1000))
        result |= 0x04;

AKM_restore:
    tmp[0] = 0 | SUPPORTS_AK89xx_HIGH_SENS;
    i2c_write(st.chip_cfg.compass_addr, AKM_REG_ASTC, 1, tmp);
    tmp[0] = SUPPORTS_AK89xx_HIGH_SENS;
    i2c_write(st.chip_cfg.compass_addr, AKM_REG_CNTL, 1, tmp);
    mpu_set_bypass(0);
    return result;
}
#endif
#endif

static int get_st_biases(long *gyro, long *accel, unsigned char hw_test)
{
    unsigned char data[MAX_PACKET_LENGTH];
    unsigned char packet_count, ii;
    unsigned short fifo_count;

    data[0] = 0x01;
    data[1] = 0;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 2, data))
        return -1;
    delay_ms(200);
    data[0] = 0;
    if (i2c_write(st.hw->addr, st.reg->int_enable, 1, data))
        return -1;
    if (i2c_write(st.hw->addr, st.reg->fifo_en, 1, data))
        return -1;
    if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 1, data))
        return -1;
    if (i2c_write(st.hw->addr, st.reg->i2c_mst, 1, data))
        return -1;
    if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, data))
        return -1;
    data[0] = BIT_FIFO_RST | BIT_DMP_RST;
    if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, data))
        return -1;
    delay_ms(15);
    data[0] = st.test->reg_lpf;
    if (i2c_write(st.hw->addr, st.reg->lpf, 1, data))
        return -1;
    data[0] = st.test->reg_rate_div;
    if (i2c_write(st.hw->addr, st.reg->rate_div, 1, data))
        return -1;
    if (hw_test)
        data[0] = st.test->reg_gyro_fsr | 0xE0;
    else
        data[0] = st.test->reg_gyro_fsr;
    if (i2c_write(st.hw->addr, st.reg->gyro_cfg, 1, data))
        return -1;

    if (hw_test)
        data[0] = st.test->reg_accel_fsr | 0xE0;
    else
        data[0] = test.reg_accel_fsr;
    if (i2c_write(st.hw->addr, st.reg->accel_cfg, 1, data))
        return -1;
    if (hw_test)
        delay_ms(200);

    /* Fill FIFO for test.wait_ms milliseconds. */
    data[0] = BIT_FIFO_EN;
    if (i2c_write(st.hw->addr, st.reg->user_ctrl, 1, data))
        return -1;

    data[0] = INV_XYZ_GYRO | INV_XYZ_ACCEL;
    if (i2c_write(st.hw->addr, st.reg->fifo_en, 1, data))
        return -1;
    delay_ms(test.wait_ms);
    data[0] = 0;
    if (i2c_write(st.hw->addr, st.reg->fifo_en, 1, data))
        return -1;

    if (i2c_read(st.hw->addr, st.reg->fifo_count_h, 2, data))
        return -1;

    fifo_count = (data[0] << 8) | data[1];
    packet_count = fifo_count / MAX_PACKET_LENGTH;
    gyro[0] = gyro[1] = gyro[2] = 0;
    accel[0] = accel[1] = accel[2] = 0;

    for (ii = 0; ii < packet_count; ii++) {
        short accel_cur[3], gyro_cur[3];
        if (i2c_read(st.hw->addr, st.reg->fifo_r_w, MAX_PACKET_LENGTH, data))
            return -1;
        accel_cur[0] = ((short)data[0] << 8) | data[1];
        accel_cur[1] = ((short)data[2] << 8) | data[3];
        accel_cur[2] = ((short)data[4] << 8) | data[5];
        accel[0] += (long)accel_cur[0];
        accel[1] += (long)accel_cur[1];
        accel[2] += (long)accel_cur[2];
        gyro_cur[0] = (((short)data[6] << 8) | data[7]);
        gyro_cur[1] = (((short)data[8] << 8) | data[9]);
        gyro_cur[2] = (((short)data[10] << 8) | data[11]);
        gyro[0] += (long)gyro_cur[0];
        gyro[1] += (long)gyro_cur[1];
        gyro[2] += (long)gyro_cur[2];
    }
#ifdef EMPL_NO_64BIT
    gyro[0] = (long)(((float)gyro[0]*65536.f) / test.gyro_sens / packet_count);
    gyro[1] = (long)(((float)gyro[1]*65536.f) / test.gyro_sens / packet_count);
    gyro[2] = (long)(((float)gyro[2]*65536.f) / test.gyro_sens / packet_count);
    if (has_accel) {
        accel[0] = (long)(((float)accel[0]*65536.f) / test.accel_sens /
            packet_count);
        accel[1] = (long)(((float)accel[1]*65536.f) / test.accel_sens /
            packet_count);
        accel[2] = (long)(((float)accel[2]*65536.f) / test.accel_sens /
            packet_count);
        /* Don't remove gravity! */
        accel[2] -= 65536L;
    }
#else
    gyro[0] = (long)(((long long)gyro[0]<<16) / test.gyro_sens / packet_count);
    gyro[1] = (long)(((long long)gyro[1]<<16) / test.gyro_sens / packet_count);
    gyro[2] = (long)(((long long)gyro[2]<<16) / test.gyro_sens / packet_count);
    accel[0] = (long)(((long long)accel[0]<<16) / test.accel_sens /
        packet_count);
    accel[1] = (long)(((long long)accel[1]<<16) / test.accel_sens /
        packet_count);
    accel[2] = (long)(((long long)accel[2]<<16) / test.accel_sens /
        packet_count);
    /* Don't remove gravity! */
    if (accel[2] > 0L)
        accel[2] -= 65536L;
    else
        accel[2] += 65536L;
#endif

    return 0;
}

/**
 *  @brief      Trigger gyro/accel/compass self-test.
 *  On success/error, the self-test returns a mask representing the sensor(s)
 *  that failed. For each bit, a one (1) represents a "pass" case; conversely,
 *  a zero (0) indicates a failure.
 *
 *  \n The mask is defined as follows:
 *  \n Bit 0:   Gyro.
 *  \n Bit 1:   Accel.
 *  \n Bit 2:   Compass.
 *
 *  \n Currently, the hardware self-test is unsupported for MPU6500. However,
 *  this function can still be used to obtain the accel and gyro biases.
 *
 *  \n This function must be called with the device either face-up or face-down
 *  (z-axis is parallel to gravity).
 *  @param[out] gyro        Gyro biases in q16 format.
 *  @param[out] accel       Accel biases (if applicable) in q16 format.
 *  @return     Result mask (see above).
 */
int mpu_run_self_test(long *gyro, long *accel)
{
#ifdef MPU6050
    const unsigned char tries = 2;
    long gyro_st[3], accel_st[3];
    unsigned char accel_result, gyro_result;
#ifdef AK89xx_SECONDARY
    unsigned char compass_result;
#endif
    int ii;
#endif
    int result;
    unsigned char accel_fsr, fifo_sensors, sensors_on;
    unsigned short gyro_fsr, sample_rate, lpf;
    unsigned char dmp_was_on;

    if (st.chip_cfg.dmp_on) {
        mpu_set_dmp_state(0);
        dmp_was_on = 1;
    } else
        dmp_was_on = 0;

    /* Get initial settings. */
    mpu_get_gyro_fsr(&gyro_fsr);
    mpu_get_accel_fsr(&accel_fsr);
    mpu_get_lpf(&lpf);
    mpu_get_sample_rate(&sample_rate);
    sensors_on = st.chip_cfg.sensors;
    mpu_get_fifo_config(&fifo_sensors);

    /* For older chips, the self-test will be different. */
#if defined MPU6050
    for (ii = 0; ii < tries; ii++)
        if (!get_st_biases(gyro, accel, 0))
            break;
    if (ii == tries) {
        /* If we reach this point, we most likely encountered an I2C error.
         * We'll just report an error for all three sensors.
         */
        result = 0;
        goto restore;
    }
    for (ii = 0; ii < tries; ii++)
        if (!get_st_biases(gyro_st, accel_st, 1))
            break;
    if (ii == tries) {
        /* Again, probably an I2C error. */
        result = 0;
        goto restore;
    }
    accel_result = accel_self_test(accel, accel_st);
    gyro_result = gyro_self_test(gyro, gyro_st);

    result = 0;
    if (!gyro_result)
        result |= 0x01;
    if (!accel_result)
        result |= 0x02;

#ifdef AK89xx_SECONDARY
    compass_result = compass_self_test();
    if (!compass_result)
        result |= 0x04;
#endif
restore:
#elif defined MPU6500
    /* For now, this function will return a "pass" result for all three sensors
     * for compatibility with current test applications.
     */
    get_st_biases(gyro, accel, 0);
    result = 0x7;
#endif
    /* Set to invalid values to ensure no I2C writes are skipped. */
    st.chip_cfg.gyro_fsr = 0xFF;
    st.chip_cfg.accel_fsr = 0xFF;
    st.chip_cfg.lpf = 0xFF;
    st.chip_cfg.sample_rate = 0xFFFF;
    st.chip_cfg.sensors = 0xFF;
    st.chip_cfg.fifo_enable = 0xFF;
    st.chip_cfg.clk_src = INV_CLK_PLL;
    mpu_set_gyro_fsr(gyro_fsr);
    mpu_set_accel_fsr(accel_fsr);
    mpu_set_lpf(lpf);
    mpu_set_sample_rate(sample_rate);
    mpu_set_sensors(sensors_on);
    mpu_configure_fifo(fifo_sensors);

    if (dmp_was_on)
        mpu_set_dmp_state(1);

    return result;
}

/**
 *  @brief      Write to the DMP memory.
 *  This function prevents I2C writes past the bank boundaries. The DMP memory
 *  is only accessible when the chip is awake.
 *  @param[in]  mem_addr    Memory location (bank << 8 | start address)
 *  @param[in]  length      Number of bytes to write.
 *  @param[in]  data        Bytes to write to memory.
 *  @return     0 if successful.
 */
int mpu_write_mem(unsigned short mem_addr, unsigned short length,
        unsigned char *data)
{
    unsigned char tmp[2];

    if (!data)
        return -1;
    if (!st.chip_cfg.sensors)
        return -1;

    tmp[0] = (unsigned char)(mem_addr >> 8);
    tmp[1] = (unsigned char)(mem_addr & 0xFF);

    /* Check bank boundaries. */
    if (tmp[1] + length > st.hw->bank_size)
        return -1;

    if (i2c_write(st.hw->addr, st.reg->bank_sel, 2, tmp))
        return -1;
    if (i2c_write(st.hw->addr, st.reg->mem_r_w, length, data))
        return -1;
    return 0;
}

/**
 *  @brief      Read from the DMP memory.
 *  This function prevents I2C reads past the bank boundaries. The DMP memory
 *  is only accessible when the chip is awake.
 *  @param[in]  mem_addr    Memory location (bank << 8 | start address)
 *  @param[in]  length      Number of bytes to read.
 *  @param[out] data        Bytes read from memory.
 *  @return     0 if successful.
 */
int mpu_read_mem(unsigned short mem_addr, unsigned short length,
        unsigned char *data)
{
    unsigned char tmp[2];

    if (!data)
        return -1;
    if (!st.chip_cfg.sensors)
        return -1;

    tmp[0] = (unsigned char)(mem_addr >> 8);
    tmp[1] = (unsigned char)(mem_addr & 0xFF);

    /* Check bank boundaries. */
    if (tmp[1] + length > st.hw->bank_size)
        return -1;

    if (i2c_write(st.hw->addr, st.reg->bank_sel, 2, tmp))
        return -1;
    if (i2c_read(st.hw->addr, st.reg->mem_r_w, length, data))
        return -1;
    return 0;
}

/**
 *  @brief      Load and verify DMP image.
 *  @param[in]  length      Length of DMP image.
 *  @param[in]  firmware    DMP code.
 *  @param[in]  start_addr  Starting address of DMP code memory.
 *  @param[in]  sample_rate Fixed sampling rate used when DMP is enabled.
 *  @return     0 if successful.
 */
int mpu_load_firmware(unsigned short length, const unsigned char *firmware,
    unsigned short start_addr, unsigned short sample_rate)
{
    unsigned short ii;
    unsigned short this_write;
    /* Must divide evenly into st.hw->bank_size to avoid bank crossings. */
#define LOAD_CHUNK  (16)
    unsigned char cur[LOAD_CHUNK], tmp[2];

    if (st.chip_cfg.dmp_loaded)
        /* DMP should only be loaded once. */
        return -1;

    if (!firmware)
        return -1;
    for (ii = 0; ii < length; ii += this_write) {
        this_write = min(LOAD_CHUNK, length - ii);
        if (mpu_write_mem(ii, this_write, (unsigned char*)&firmware[ii]))
            return -1;
        if (mpu_read_mem(ii, this_write, cur))
            return -1;
        if (memcmp(firmware+ii, cur, this_write))
            return -2;
    }

    /* Set program start address. */
    tmp[0] = start_addr >> 8;
    tmp[1] = start_addr & 0xFF;
    if (i2c_write(st.hw->addr, st.reg->prgm_start_h, 2, tmp))
        return -1;

    st.chip_cfg.dmp_loaded = 1;
    st.chip_cfg.dmp_sample_rate = sample_rate;
    return 0;
}

/**
 *  @brief      Enable/disable DMP support.
 *  @param[in]  enable  1 to turn on the DMP.
 *  @return     0 if successful.
 */
int mpu_set_dmp_state(unsigned char enable)
{
    unsigned char tmp;
    if (st.chip_cfg.dmp_on == enable)
        return 0;

    if (enable) {
        if (!st.chip_cfg.dmp_loaded)
            return -1;
        /* Disable data ready interrupt. */
        set_int_enable(0);
        /* Disable bypass mode. */
        mpu_set_bypass(0);
        /* Keep constant sample rate, FIFO rate controlled by DMP. */
        mpu_set_sample_rate(st.chip_cfg.dmp_sample_rate);
        /* Remove FIFO elements. */
        tmp = 0;
        i2c_write(st.hw->addr, 0x23, 1, &tmp);
        st.chip_cfg.dmp_on = 1;
        /* Enable DMP interrupt. */
        set_int_enable(1);
        mpu_reset_fifo();
    } else {
        /* Disable DMP interrupt. */
        set_int_enable(0);
        /* Restore FIFO settings. */
        tmp = st.chip_cfg.fifo_enable;
        i2c_write(st.hw->addr, 0x23, 1, &tmp);
        st.chip_cfg.dmp_on = 0;
        mpu_reset_fifo();
    }
    return 0;
}

/**
 *  @brief      Get DMP state.
 *  @param[out] enabled 1 if enabled.
 *  @return     0 if successful.
 */
int mpu_get_dmp_state(unsigned char *enabled)
{
    enabled[0] = st.chip_cfg.dmp_on;
    return 0;
}


/* This initialization is similar to the one in ak8975.c. */
int setup_compass(void)
{
#ifdef AK89xx_SECONDARY
    unsigned char data[4], akm_addr;

    mpu_set_bypass(1);

    /* Find compass. Possible addresses range from 0x0C to 0x0F. */
    for (akm_addr = 0x0C; akm_addr <= 0x0F; akm_addr++) {
        int result;
        result = i2c_read(akm_addr, AKM_REG_WHOAMI, 1, data);
        if (!result && (data[0] == AKM_WHOAMI))
            break;
    }

    if (akm_addr > 0x0F) {
        /* TODO: Handle this case in all compass-related functions. */
        //("Compass not found.\n");
        return -1;
    }

    st.chip_cfg.compass_addr = akm_addr;

    data[0] = AKM_POWER_DOWN;
    if (i2c_write(st.chip_cfg.compass_addr, AKM_REG_CNTL, 1, data))
        return -1;
    delay_ms(1);

    data[0] = AKM_FUSE_ROM_ACCESS;
    if (i2c_write(st.chip_cfg.compass_addr, AKM_REG_CNTL, 1, data))
        return -1;
    delay_ms(1);

    /* Get sensitivity adjustment data from fuse ROM. */
    if (i2c_read(st.chip_cfg.compass_addr, AKM_REG_ASAX, 3, data))
        return -1;
    st.chip_cfg.mag_sens_adj[0] = (long)data[0] + 128;
    st.chip_cfg.mag_sens_adj[1] = (long)data[1] + 128;
    st.chip_cfg.mag_sens_adj[2] = (long)data[2] + 128;

    data[0] = AKM_POWER_DOWN;
    if (i2c_write(st.chip_cfg.compass_addr, AKM_REG_CNTL, 1, data))
        return -1;
    delay_ms(1);

    mpu_set_bypass(0);

    /* Set up master mode, master clock, and ES bit. */
    data[0] = 0x40;
    if (i2c_write(st.hw->addr, st.reg->i2c_mst, 1, data))
        return -1;

    /* Slave 0 reads from AKM data registers. */
    data[0] = BIT_I2C_READ | st.chip_cfg.compass_addr;
    if (i2c_write(st.hw->addr, st.reg->s0_addr, 1, data))
        return -1;

    /* Compass reads start at this register. */
    data[0] = AKM_REG_ST1;
    if (i2c_write(st.hw->addr, st.reg->s0_reg, 1, data))
        return -1;

    /* Enable slave 0, 8-byte reads. */
    data[0] = BIT_SLAVE_EN | 8;
    if (i2c_write(st.hw->addr, st.reg->s0_ctrl, 1, data))
        return -1;

    /* Slave 1 changes AKM measurement mode. */
    data[0] = st.chip_cfg.compass_addr;
    if (i2c_write(st.hw->addr, st.reg->s1_addr, 1, data))
        return -1;

    /* AKM measurement mode register. */
    data[0] = AKM_REG_CNTL;
    if (i2c_write(st.hw->addr, st.reg->s1_reg, 1, data))
        return -1;

    /* Enable slave 1, 1-byte writes. */
    data[0] = BIT_SLAVE_EN | 1;
    if (i2c_write(st.hw->addr, st.reg->s1_ctrl, 1, data))
        return -1;

    /* Set slave 1 data. */
    data[0] = AKM_SINGLE_MEASUREMENT;
    if (i2c_write(st.hw->addr, st.reg->s1_do, 1, data))
        return -1;

    /* Trigger slave 0 and slave 1 actions at each sample. */
    data[0] = 0x03;
    if (i2c_write(st.hw->addr, st.reg->i2c_delay_ctrl, 1, data))
        return -1;

#ifdef MPU9150
    /* For the MPU9150, the auxiliary I2C bus needs to be set to VDD. */
    data[0] = BIT_I2C_MST_VDDIO;
    if (i2c_write(st.hw->addr, st.reg->yg_offs_tc, 1, data))
        return -1;
#endif

    return 0;
#else
    return -1;
#endif
}

/**
 *  @brief      Read raw compass data.
 *  @param[out] data        Raw data in hardware units.
 *  @param[out] timestamp   Timestamp in milliseconds. Null if not needed.
 *  @return     0 if successful.
 */
int mpu_get_compass_reg(short *data, unsigned long *timestamp)
{
#ifdef AK89xx_SECONDARY
    unsigned char tmp[9];

    if (!(st.chip_cfg.sensors & INV_XYZ_COMPASS))
        return -1;

#ifdef AK89xx_BYPASS
    if (i2c_read(st.chip_cfg.compass_addr, AKM_REG_ST1, 8, tmp))
        return -1;
    tmp[8] = AKM_SINGLE_MEASUREMENT;
    if (i2c_write(st.chip_cfg.compass_addr, AKM_REG_CNTL, 1, tmp+8))
        return -1;
#else
    if (i2c_read(st.hw->addr, st.reg->raw_compass, 8, tmp))
        return -1;
#endif

#if defined AK8975_SECONDARY
    /* AK8975 doesn't have the overrun error bit. */
    if (!(tmp[0] & AKM_DATA_READY))
        return -2;
    if ((tmp[7] & AKM_OVERFLOW) || (tmp[7] & AKM_DATA_ERROR))
        return -3;
#elif defined AK8963_SECONDARY
    /* AK8963 doesn't have the data read error bit. */
    if (!(tmp[0] & AKM_DATA_READY) || (tmp[0] & AKM_DATA_OVERRUN))
        return -2;
    if (tmp[7] & AKM_OVERFLOW)
        return -3;
#endif
    data[0] = (tmp[2] << 8) | tmp[1];
    data[1] = (tmp[4] << 8) | tmp[3];
    data[2] = (tmp[6] << 8) | tmp[5];

    data[0] = ((long)data[0] * st.chip_cfg.mag_sens_adj[0]) >> 8;
    data[1] = ((long)data[1] * st.chip_cfg.mag_sens_adj[1]) >> 8;
    data[2] = ((long)data[2] * st.chip_cfg.mag_sens_adj[2]) >> 8;

    if (timestamp)
        get_ms(timestamp);
    return 0;
#else
    return -1;
#endif
}

/**
 *  @brief      Get the compass full-scale range.
 *  @param[out] fsr Current full-scale range.
 *  @return     0 if successful.
 */
int mpu_get_compass_fsr(unsigned short *fsr)
{
#ifdef AK89xx_SECONDARY
    fsr[0] = st.hw->compass_fsr;
    return 0;
#else
    return -1;
#endif
}

/**
 *  @brief      Enters LP accel motion interrupt mode.
 *  The behavior of this feature is very different between the MPU6050 and the
 *  MPU6500. Each chip's version of this feature is explained below.
 *
 *  \n MPU6050:
 *  \n When this mode is first enabled, the hardware captures a single accel
 *  sample, and subsequent samples are compared with this one to determine if
 *  the device is in motion. Therefore, whenever this "locked" sample needs to
 *  be changed, this function must be called again.
 *
 *  \n The hardware motion threshold can be between 32mg and 8160mg in 32mg
 *  increments.
 *
 *  \n Low-power accel mode supports the following frequencies:
 *  \n 1.25Hz, 5Hz, 20Hz, 40Hz
 *
 *  \n MPU6500:
 *  \n Unlike the MPU6050 version, the hardware does not "lock in" a reference
 *  sample. The hardware monitors the accel data and detects any large change
 *  over a short period of time.
 *
 *  \n The hardware motion threshold can be between 4mg and 1020mg in 4mg
 *  increments.
 *
 *  \n MPU6500 Low-power accel mode supports the following frequencies:
 *  \n 1.25Hz, 2.5Hz, 5Hz, 10Hz, 20Hz, 40Hz, 80Hz, 160Hz, 320Hz, 640Hz
 *
 *  \n\n NOTES:
 *  \n The driver will round down @e thresh to the nearest supported value if
 *  an unsupported threshold is selected.
 *  \n To select a fractional wake-up frequency, round down the value passed to
 *  @e lpa_freq.
 *  \n The MPU6500 does not support a delay parameter. If this function is used
 *  for the MPU6500, the value passed to @e time will be ignored.
 *  \n To disable this mode, set @e lpa_freq to zero. The driver will restore
 *  the previous configuration.
 *
 *  @param[in]  thresh      Motion threshold in mg.
 *  @param[in]  time        Duration in milliseconds that the accel data must
 *                          exceed @e thresh before motion is reported.
 *  @param[in]  lpa_freq    Minimum sampling rate, or zero to disable.
 *  @return     0 if successful.
 */
int mpu_lp_motion_interrupt(unsigned short thresh, unsigned char time,
    unsigned char lpa_freq)
{
    unsigned char data[3];

    if (lpa_freq) {
        unsigned char thresh_hw;

#if defined MPU6050
        /* TODO: Make these const/#defines. */
        /* 1LSb = 32mg. */
        if (thresh > 8160)
            thresh_hw = 255;
        else if (thresh < 32)
            thresh_hw = 1;
        else
            thresh_hw = thresh >> 5;
#elif defined MPU6500
        /* 1LSb = 4mg. */
        if (thresh > 1020)
            thresh_hw = 255;
        else if (thresh < 4)
            thresh_hw = 1;
        else
            thresh_hw = thresh >> 2;
#endif

        if (!time)
            /* Minimum duration must be 1ms. */
            time = 1;

#if defined MPU6050
        if (lpa_freq > 40)
#elif defined MPU6500
        if (lpa_freq > 640)
#endif
            /* At this point, the chip has not been re-configured, so the
             * function can safely exit.
             */
            return -1;

        if (!st.chip_cfg.int_motion_only) {
            /* Store current settings for later. */
            if (st.chip_cfg.dmp_on) {
                mpu_set_dmp_state(0);
                st.chip_cfg.cache.dmp_on = 1;
            } else
                st.chip_cfg.cache.dmp_on = 0;
            mpu_get_gyro_fsr(&st.chip_cfg.cache.gyro_fsr);
            mpu_get_accel_fsr(&st.chip_cfg.cache.accel_fsr);
            mpu_get_lpf(&st.chip_cfg.cache.lpf);
            mpu_get_sample_rate(&st.chip_cfg.cache.sample_rate);
            st.chip_cfg.cache.sensors_on = st.chip_cfg.sensors;
            mpu_get_fifo_config(&st.chip_cfg.cache.fifo_sensors);
        }

#ifdef MPU6050
        /* Disable hardware interrupts for now. */
        set_int_enable(0);

        /* Enter full-power accel-only mode. */
        mpu_lp_accel_mode(0);

        /* Override current LPF (and HPF) settings to obtain a valid accel
         * reading.
         */
        data[0] = INV_FILTER_256HZ_NOLPF2;
        if (i2c_write(st.hw->addr, st.reg->lpf, 1, data))
            return -1;

        /* NOTE: Digital high pass filter should be configured here. Since this
         * driver doesn't modify those bits anywhere, they should already be
         * cleared by default.
         */

        /* Configure the device to send motion interrupts. */
        /* Enable motion interrupt. */
        data[0] = BIT_MOT_INT_EN;
        if (i2c_write(st.hw->addr, st.reg->int_enable, 1, data))
            goto lp_int_restore;

        /* Set motion interrupt parameters. */
        data[0] = thresh_hw;
        data[1] = time;
        if (i2c_write(st.hw->addr, st.reg->motion_thr, 2, data))
            goto lp_int_restore;

        /* Force hardware to "lock" current accel sample. */
        delay_ms(5);
        data[0] = (st.chip_cfg.accel_fsr << 3) | BITS_HPF;
        if (i2c_write(st.hw->addr, st.reg->accel_cfg, 1, data))
            goto lp_int_restore;

        /* Set up LP accel mode. */
        data[0] = BIT_LPA_CYCLE;
        if (lpa_freq == 1)
            data[1] = INV_LPA_1_25HZ;
        else if (lpa_freq <= 5)
            data[1] = INV_LPA_5HZ;
        else if (lpa_freq <= 20)
            data[1] = INV_LPA_20HZ;
        else
            data[1] = INV_LPA_40HZ;
        data[1] = (data[1] << 6) | BIT_STBY_XYZG;
        if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 2, data))
            goto lp_int_restore;

        st.chip_cfg.int_motion_only = 1;
        return 0;
#elif defined MPU6500
        /* Disable hardware interrupts. */
        set_int_enable(0);

        /* Enter full-power accel-only mode, no FIFO/DMP. */
        data[0] = 0;
        data[1] = 0;
        data[2] = BIT_STBY_XYZG;
        if (i2c_write(st.hw->addr, st.reg->user_ctrl, 3, data))
            goto lp_int_restore;

        /* Set motion threshold. */
        data[0] = thresh_hw;
        if (i2c_write(st.hw->addr, st.reg->motion_thr, 1, data))
            goto lp_int_restore;

        /* Set wake frequency. */
        if (lpa_freq == 1)
            data[0] = INV_LPA_1_25HZ;
        else if (lpa_freq == 2)
            data[0] = INV_LPA_2_5HZ;
        else if (lpa_freq <= 5)
            data[0] = INV_LPA_5HZ;
        else if (lpa_freq <= 10)
            data[0] = INV_LPA_10HZ;
        else if (lpa_freq <= 20)
            data[0] = INV_LPA_20HZ;
        else if (lpa_freq <= 40)
            data[0] = INV_LPA_40HZ;
        else if (lpa_freq <= 80)
            data[0] = INV_LPA_80HZ;
        else if (lpa_freq <= 160)
            data[0] = INV_LPA_160HZ;
        else if (lpa_freq <= 320)
            data[0] = INV_LPA_320HZ;
        else
            data[0] = INV_LPA_640HZ;
        if (i2c_write(st.hw->addr, st.reg->lp_accel_odr, 1, data))
            goto lp_int_restore;

        /* Enable motion interrupt (MPU6500 version). */
        data[0] = BITS_WOM_EN;
        if (i2c_write(st.hw->addr, st.reg->accel_intel, 1, data))
            goto lp_int_restore;

        /* Enable cycle mode. */
        data[0] = BIT_LPA_CYCLE;
        if (i2c_write(st.hw->addr, st.reg->pwr_mgmt_1, 1, data))
            goto lp_int_restore;

        /* Enable interrupt. */
        data[0] = BIT_MOT_INT_EN;
        if (i2c_write(st.hw->addr, st.reg->int_enable, 1, data))
            goto lp_int_restore;

        st.chip_cfg.int_motion_only = 1;
        return 0;
#endif
    } else {
        /* Don't "restore" the previous state if no state has been saved. */
        int ii;
        char *cache_ptr = (char*)&st.chip_cfg.cache;
        for (ii = 0; ii < sizeof(st.chip_cfg.cache); ii++) {
            if (cache_ptr[ii] != 0)
                goto lp_int_restore;
        }
        /* If we reach this point, motion interrupt mode hasn't been used yet. */
        return -1;
    }
lp_int_restore:
    /* Set to invalid values to ensure no I2C writes are skipped. */
    st.chip_cfg.gyro_fsr = 0xFF;
    st.chip_cfg.accel_fsr = 0xFF;
    st.chip_cfg.lpf = 0xFF;
    st.chip_cfg.sample_rate = 0xFFFF;
    st.chip_cfg.sensors = 0xFF;
    st.chip_cfg.fifo_enable = 0xFF;
    st.chip_cfg.clk_src = INV_CLK_PLL;
    mpu_set_sensors(st.chip_cfg.cache.sensors_on);
    mpu_set_gyro_fsr(st.chip_cfg.cache.gyro_fsr);
    mpu_set_accel_fsr(st.chip_cfg.cache.accel_fsr);
    mpu_set_lpf(st.chip_cfg.cache.lpf);
    mpu_set_sample_rate(st.chip_cfg.cache.sample_rate);
    mpu_configure_fifo(st.chip_cfg.cache.fifo_sensors);

    if (st.chip_cfg.cache.dmp_on)
        mpu_set_dmp_state(1);

#ifdef MPU6500
    /* Disable motion interrupt (MPU6500 version). */
    data[0] = 0;
    if (i2c_write(st.hw->addr, st.reg->accel_intel, 1, data))
        goto lp_int_restore;
#endif

    st.chip_cfg.int_motion_only = 0;
    return 0;
}
//////////////////////////////////////////////////////////////////////////////////
//添加的代码部分 
//////////////////////////////////////////////////////////////////////////////////   
//本程序只供学习使用,未经作者许可,不得用于其它任何用途
//ALIENTEK STM32开发板 
//MPU6050 DMP 驱动代码     
//正点原子@ALIENTEK
//技术论坛:www.openedv.com
//创建日期:2015/1/17
//版本:V1.0
//版权所有,盗版必究。
//Copyright(C) 广州市星翼电子科技有限公司 2009-2019
//All rights reserved                                     
////////////////////////////////////////////////////////////////////////////////// 

//q30格式,long转float时的除数.
#define q30  1073741824.0f

//陀螺仪方向设置
static signed char gyro_orientation[9] = { 1, 0, 0,
                                           0, 1, 0,
                                           0, 0, 1};
//MPU6050自测试
//返回值:0,正常
//    其他,失败
unsigned char run_self_test(void)
{
    int result;
    //char test_packet[4] = {0};
    long gyro[3], accel[3]; 
    result = mpu_run_self_test(gyro, accel);
    if (result == 0x3) 
    {
        /* Test passed. We can trust the gyro data here, so let's push it down
        * to the DMP.
        */
        float sens;
        unsigned short accel_sens;
        mpu_get_gyro_sens(&sens);
        gyro[0] = (long)(gyro[0] * sens);
        gyro[1] = (long)(gyro[1] * sens);
        gyro[2] = (long)(gyro[2] * sens);
        dmp_set_gyro_bias(gyro);
        mpu_get_accel_sens(&accel_sens);
        accel[0] *= accel_sens;
        accel[1] *= accel_sens;
        accel[2] *= accel_sens;
        dmp_set_accel_bias(accel);
        return 0;
    }else return 1;
}
//陀螺仪方向控制
unsigned short inv_orientation_matrix_to_scalar(
    const signed char *mtx)
{
    unsigned short scalar; 
    /*
       XYZ  010_001_000 Identity Matrix
       XZY  001_010_000
       YXZ  010_000_001
       YZX  000_010_001
       ZXY  001_000_010
       ZYX  000_001_010
     */

    scalar = inv_row_2_scale(mtx);
    scalar |= inv_row_2_scale(mtx + 3) << 3;
    scalar |= inv_row_2_scale(mtx + 6) << 6;


    return scalar;
}
//方向转换
unsigned short inv_row_2_scale(const signed char *row)
{
    unsigned short b;

    if (row[0] > 0)
        b = 0;
    else if (row[0] < 0)
        b = 4;
    else if (row[1] > 0)
        b = 1;
    else if (row[1] < 0)
        b = 5;
    else if (row[2] > 0)
        b = 2;
    else if (row[2] < 0)
        b = 6;
    else
        b = 7;      // error
    return b;
}
//空函数,未用到.
void mget_ms(unsigned long *time)
{

}
//mpu6050,dmp初始化
//返回值:0,正常
//    其他,失败
unsigned char mpu_dmp_init(void)
{
    unsigned char res=0;
    MPU_IIC_Init();     //初始化IIC总线
    if(mpu_init()==0)   //初始化MPU6050
    {    
        res=mpu_set_sensors(INV_XYZ_GYRO|INV_XYZ_ACCEL);//设置所需要的传感器
        if(res)return 1; 
        res=mpu_configure_fifo(INV_XYZ_GYRO|INV_XYZ_ACCEL);//设置FIFO
        if(res)return 2; 
        res=mpu_set_sample_rate(DEFAULT_MPU_HZ);    //设置采样率
        if(res)return 3; 
        res=dmp_load_motion_driver_firmware();      //加载dmp固件
        if(res)return 4; 
        res=dmp_set_orientation(inv_orientation_matrix_to_scalar(gyro_orientation));//设置陀螺仪方向
        if(res)return 5; 
        res=dmp_enable_feature(DMP_FEATURE_6X_LP_QUAT|DMP_FEATURE_TAP|  //设置dmp功能
            DMP_FEATURE_ANDROID_ORIENT|DMP_FEATURE_SEND_RAW_ACCEL|DMP_FEATURE_SEND_CAL_GYRO|
            DMP_FEATURE_GYRO_CAL);
        if(res)return 6; 
        res=dmp_set_fifo_rate(DEFAULT_MPU_HZ);  //设置DMP输出速率(最大不超过200Hz)
        if(res)return 7;   
        res=run_self_test();        //自检
        if(res)return 8;    
        res=mpu_set_dmp_state(1);   //使能DMP
        if(res)return 9;     
    }else return 10;
    return 0;
}
//得到dmp处理后的数据(注意,本函数需要比较多堆栈,局部变量有点多)
//pitch:俯仰角 精度:0.1°   范围:-90.0° <---> +90.0°
//roll:横滚角  精度:0.1°   范围:-180.0°<---> +180.0°
//yaw:航向角   精度:0.1°   范围:-180.0°<---> +180.0°
//返回值:0,正常
//    其他,失败
unsigned char mpu_dmp_get_data(float *pitch,float *roll,float *yaw)
{
    float q0=1.0f,q1=0.0f,q2=0.0f,q3=0.0f;
    unsigned long sensor_timestamp;
    short gyro[3], accel[3], sensors;
    unsigned char more;
    long quat[4]; 
    if(dmp_read_fifo(gyro, accel, quat, &sensor_timestamp, &sensors,&more))return 1;     
    /* Gyro and accel data are written to the FIFO by the DMP in chip frame and hardware units.
     * This behavior is convenient because it keeps the gyro and accel outputs of dmp_read_fifo and mpu_read_fifo consistent.
    **/
    /*if (sensors & INV_XYZ_GYRO )
    send_packet(PACKET_TYPE_GYRO, gyro);
    if (sensors & INV_XYZ_ACCEL)
    send_packet(PACKET_TYPE_ACCEL, accel); */
    /* Unlike gyro and accel, quaternions are written to the FIFO in the body frame, q30.
     * The orientation is set by the scalar passed to dmp_set_orientation during initialization. 
    **/
    if(sensors&INV_WXYZ_QUAT) 
    {
        q0 = quat[0] / q30; //q30格式转换为浮点数
        q1 = quat[1] / q30;
        q2 = quat[2] / q30;
        q3 = quat[3] / q30; 
        //计算得到俯仰角/横滚角/航向角
        *pitch = asin(-2 * q1 * q3 + 2 * q0* q2)* 57.3; // pitch
        *roll  = atan2(2 * q2 * q3 + 2 * q0 * q1, -2 * q1 * q1 - 2 * q2* q2 + 1)* 57.3; // roll
        *yaw   = atan2(2*(q1*q2 + q0*q3),q0*q0+q1*q1-q2*q2-q3*q3) * 57.3;   //yaw
    }else return 2;
    return 0;
}

//定义目标板采用MSP430
#define  MOTION_DRIVER_TARGET_MSP430

/* The following functions must be defined for this platform:
 * i2c_write(unsigned char slave_addr, unsigned char reg_addr,
 *      unsigned char length, unsigned char const *data)
 * i2c_read(unsigned char slave_addr, unsigned char reg_addr,
 *      unsigned char length, unsigned char *data)
 * delay_ms(unsigned long num_ms)
 * get_ms(unsigned long *count)
 */
#if defined MOTION_DRIVER_TARGET_MSP430
//#include "msp430.h"
//#include "msp430_clock.h"
//#define delay_ms    delay_ms
#define get_ms      mget_ms
//#define //       printf
//#define //       printf

#elif defined EMPL_TARGET_MSP430
#include "msp430.h"
#include "msp430_clock.h"
#include "log.h"
#define delay_ms    msp430_delay_ms
#define get_ms      msp430_get_clock_ms
//#define //       MPL_LOGI
//#define //       MPL_LOGE

#elif defined EMPL_TARGET_UC3L0
/* Instead of using the standard TWI driver from the ASF library, we're using
 * a TWI driver that follows the slave address + register address convention.
 */
#include "delay.h"
#include "sysclk.h"
#include "log.h"
#include "uc3l0_clock.h"
/* delay_ms is a function already defined in ASF. */
#define get_ms  uc3l0_get_clock_ms
//#define //       MPL_LOGI
//#define //       MPL_LOGE

#else
#error  Gyro driver is missing the system layer implementations.
#endif

/* These defines are copied from dmpDefaultMPU6050.c in the general MPL
 * releases. These defines may change for each DMP image, so be sure to modify
 * these values when switching to a new image.
 */
#define CFG_LP_QUAT             (2712)
#define END_ORIENT_TEMP         (1866)
#define CFG_27                  (2742)
#define CFG_20                  (2224)
#define CFG_23                  (2745)
#define CFG_FIFO_ON_EVENT       (2690)
#define END_PREDICTION_UPDATE   (1761)
#define CGNOTICE_INTR           (2620)
#define X_GRT_Y_TMP             (1358)
#define CFG_DR_INT              (1029)
#define CFG_AUTH                (1035)
#define UPDATE_PROP_ROT         (1835)
#define END_COMPARE_Y_X_TMP2    (1455)
#define SKIP_X_GRT_Y_TMP        (1359)
#define SKIP_END_COMPARE        (1435)
#define FCFG_3                  (1088)
#define FCFG_2                  (1066)
#define FCFG_1                  (1062)
#define END_COMPARE_Y_X_TMP3    (1434)
#define FCFG_7                  (1073)
#define FCFG_6                  (1106)
#define FLAT_STATE_END          (1713)
#define SWING_END_4             (1616)
#define SWING_END_2             (1565)
#define SWING_END_3             (1587)
#define SWING_END_1             (1550)
#define CFG_8                   (2718)
#define CFG_15                  (2727)
#define CFG_16                  (2746)
#define CFG_EXT_GYRO_BIAS       (1189)
#define END_COMPARE_Y_X_TMP     (1407)
#define DO_NOT_UPDATE_PROP_ROT  (1839)
#define CFG_7                   (1205)
#define FLAT_STATE_END_TEMP     (1683)
#define END_COMPARE_Y_X         (1484)
#define SKIP_SWING_END_1        (1551)
#define SKIP_SWING_END_3        (1588)
#define SKIP_SWING_END_2        (1566)
#define TILTG75_START           (1672)
#define CFG_6                   (2753)
#define TILTL75_END             (1669)
#define END_ORIENT              (1884)
#define CFG_FLICK_IN            (2573)
#define TILTL75_START           (1643)
#define CFG_MOTION_BIAS         (1208)
#define X_GRT_Y                 (1408)
#define TEMPLABEL               (2324)
#define CFG_ANDROID_ORIENT_INT  (1853)
#define CFG_GYRO_RAW_DATA       (2722)
#define X_GRT_Y_TMP2            (1379)

#define D_0_22                  (22+512)
#define D_0_24                  (24+512)

#define D_0_36                  (36)
#define D_0_52                  (52)
#define D_0_96                  (96)
#define D_0_104                 (104)
#define D_0_108                 (108)
#define D_0_163                 (163)
#define D_0_188                 (188)
#define D_0_192                 (192)
#define D_0_224                 (224)
#define D_0_228                 (228)
#define D_0_232                 (232)
#define D_0_236                 (236)

#define D_1_2                   (256 + 2)
#define D_1_4                   (256 + 4)
#define D_1_8                   (256 + 8)
#define D_1_10                  (256 + 10)
#define D_1_24                  (256 + 24)
#define D_1_28                  (256 + 28)
#define D_1_36                  (256 + 36)
#define D_1_40                  (256 + 40)
#define D_1_44                  (256 + 44)
#define D_1_72                  (256 + 72)
#define D_1_74                  (256 + 74)
#define D_1_79                  (256 + 79)
#define D_1_88                  (256 + 88)
#define D_1_90                  (256 + 90)
#define D_1_92                  (256 + 92)
#define D_1_96                  (256 + 96)
#define D_1_98                  (256 + 98)
#define D_1_106                 (256 + 106)
#define D_1_108                 (256 + 108)
#define D_1_112                 (256 + 112)
#define D_1_128                 (256 + 144)
#define D_1_152                 (256 + 12)
#define D_1_160                 (256 + 160)
#define D_1_176                 (256 + 176)
#define D_1_178                 (256 + 178)
#define D_1_218                 (256 + 218)
#define D_1_232                 (256 + 232)
#define D_1_236                 (256 + 236)
#define D_1_240                 (256 + 240)
#define D_1_244                 (256 + 244)
#define D_1_250                 (256 + 250)
#define D_1_252                 (256 + 252)
#define D_2_12                  (512 + 12)
#define D_2_96                  (512 + 96)
#define D_2_108                 (512 + 108)
#define D_2_208                 (512 + 208)
#define D_2_224                 (512 + 224)
#define D_2_236                 (512 + 236)
#define D_2_244                 (512 + 244)
#define D_2_248                 (512 + 248)
#define D_2_252                 (512 + 252)

#define CPASS_BIAS_X            (35 * 16 + 4)
#define CPASS_BIAS_Y            (35 * 16 + 8)
#define CPASS_BIAS_Z            (35 * 16 + 12)
#define CPASS_MTX_00            (36 * 16)
#define CPASS_MTX_01            (36 * 16 + 4)
#define CPASS_MTX_02            (36 * 16 + 8)
#define CPASS_MTX_10            (36 * 16 + 12)
#define CPASS_MTX_11            (37 * 16)
#define CPASS_MTX_12            (37 * 16 + 4)
#define CPASS_MTX_20            (37 * 16 + 8)
#define CPASS_MTX_21            (37 * 16 + 12)
#define CPASS_MTX_22            (43 * 16 + 12)
#define D_EXT_GYRO_BIAS_X       (61 * 16)
#define D_EXT_GYRO_BIAS_Y       (61 * 16) + 4
#define D_EXT_GYRO_BIAS_Z       (61 * 16) + 8
#define D_ACT0                  (40 * 16)
#define D_ACSX                  (40 * 16 + 4)
#define D_ACSY                  (40 * 16 + 8)
#define D_ACSZ                  (40 * 16 + 12)

#define FLICK_MSG               (45 * 16 + 4)
#define FLICK_COUNTER           (45 * 16 + 8)
#define FLICK_LOWER             (45 * 16 + 12)
#define FLICK_UPPER             (46 * 16 + 12)

#define D_AUTH_OUT              (992)
#define D_AUTH_IN               (996)
#define D_AUTH_A                (1000)
#define D_AUTH_B                (1004)

#define D_PEDSTD_BP_B           (768 + 0x1C)
#define D_PEDSTD_HP_A           (768 + 0x78)
#define D_PEDSTD_HP_B           (768 + 0x7C)
#define D_PEDSTD_BP_A4          (768 + 0x40)
#define D_PEDSTD_BP_A3          (768 + 0x44)
#define D_PEDSTD_BP_A2          (768 + 0x48)
#define D_PEDSTD_BP_A1          (768 + 0x4C)
#define D_PEDSTD_INT_THRSH      (768 + 0x68)
#define D_PEDSTD_CLIP           (768 + 0x6C)
#define D_PEDSTD_SB             (768 + 0x28)
#define D_PEDSTD_SB_TIME        (768 + 0x2C)
#define D_PEDSTD_PEAKTHRSH      (768 + 0x98)
#define D_PEDSTD_TIML           (768 + 0x2A)
#define D_PEDSTD_TIMH           (768 + 0x2E)
#define D_PEDSTD_PEAK           (768 + 0X94)
#define D_PEDSTD_STEPCTR        (768 + 0x60)
#define D_PEDSTD_TIMECTR        (964)
#define D_PEDSTD_DECI           (768 + 0xA0)

#define D_HOST_NO_MOT           (976)
#define D_ACCEL_BIAS            (660)

#define D_ORIENT_GAP            (76)

#define D_TILT0_H               (48)
#define D_TILT0_L               (50)
#define D_TILT1_H               (52)
#define D_TILT1_L               (54)
#define D_TILT2_H               (56)
#define D_TILT2_L               (58)
#define D_TILT3_H               (60)
#define D_TILT3_L               (62)

#define DMP_CODE_SIZE           (3062)

static const unsigned char dmp_memory[DMP_CODE_SIZE] = {
    /* bank # 0 */
    0x00, 0x00, 0x70, 0x00, 0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x02, 0x00, 0x03, 0x00, 0x00,
    0x00, 0x65, 0x00, 0x54, 0xff, 0xef, 0x00, 0x00, 0xfa, 0x80, 0x00, 0x0b, 0x12, 0x82, 0x00, 0x01,
    0x03, 0x0c, 0x30, 0xc3, 0x0e, 0x8c, 0x8c, 0xe9, 0x14, 0xd5, 0x40, 0x02, 0x13, 0x71, 0x0f, 0x8e,
    0x38, 0x83, 0xf8, 0x83, 0x30, 0x00, 0xf8, 0x83, 0x25, 0x8e, 0xf8, 0x83, 0x30, 0x00, 0xf8, 0x83,
    0xff, 0xff, 0xff, 0xff, 0x0f, 0xfe, 0xa9, 0xd6, 0x24, 0x00, 0x04, 0x00, 0x1a, 0x82, 0x79, 0xa1,
    0x00, 0x00, 0x00, 0x3c, 0xff, 0xff, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x38, 0x83, 0x6f, 0xa2,
    0x00, 0x3e, 0x03, 0x30, 0x40, 0x00, 0x00, 0x00, 0x02, 0xca, 0xe3, 0x09, 0x3e, 0x80, 0x00, 0x00,
    0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00, 0x00, 0x60, 0x00, 0x00, 0x00,
    0x00, 0x0c, 0x00, 0x00, 0x00, 0x0c, 0x18, 0x6e, 0x00, 0x00, 0x06, 0x92, 0x0a, 0x16, 0xc0, 0xdf,
    0xff, 0xff, 0x02, 0x56, 0xfd, 0x8c, 0xd3, 0x77, 0xff, 0xe1, 0xc4, 0x96, 0xe0, 0xc5, 0xbe, 0xaa,
    0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x0b, 0x2b, 0x00, 0x00, 0x16, 0x57, 0x00, 0x00, 0x03, 0x59,
    0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1d, 0xfa, 0x00, 0x02, 0x6c, 0x1d, 0x00, 0x00, 0x00, 0x00,
    0x3f, 0xff, 0xdf, 0xeb, 0x00, 0x3e, 0xb3, 0xb6, 0x00, 0x0d, 0x22, 0x78, 0x00, 0x00, 0x2f, 0x3c,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x19, 0x42, 0xb5, 0x00, 0x00, 0x39, 0xa2, 0x00, 0x00, 0xb3, 0x65,
    0xd9, 0x0e, 0x9f, 0xc9, 0x1d, 0xcf, 0x4c, 0x34, 0x30, 0x00, 0x00, 0x00, 0x50, 0x00, 0x00, 0x00,
    0x3b, 0xb6, 0x7a, 0xe8, 0x00, 0x64, 0x00, 0x00, 0x00, 0xc8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    /* bank # 1 */
    0x10, 0x00, 0x00, 0x00, 0x10, 0x00, 0xfa, 0x92, 0x10, 0x00, 0x22, 0x5e, 0x00, 0x0d, 0x22, 0x9f,
    0x00, 0x01, 0x00, 0x00, 0x00, 0x32, 0x00, 0x00, 0xff, 0x46, 0x00, 0x00, 0x63, 0xd4, 0x00, 0x00,
    0x10, 0x00, 0x00, 0x00, 0x04, 0xd6, 0x00, 0x00, 0x04, 0xcc, 0x00, 0x00, 0x04, 0xcc, 0x00, 0x00,
    0x00, 0x00, 0x10, 0x72, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x06, 0x00, 0x02, 0x00, 0x05, 0x00, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x64, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0x00, 0x05, 0x00, 0x64, 0x00, 0x20, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00, 0x00, 0x03, 0x00,
    0x00, 0x00, 0x00, 0x32, 0xf8, 0x98, 0x00, 0x00, 0xff, 0x65, 0x00, 0x00, 0x83, 0x0f, 0x00, 0x00,
    0xff, 0x9b, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
    0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x00, 0x00, 0xb2, 0x6a, 0x00, 0x02, 0x00, 0x00,
    0x00, 0x01, 0xfb, 0x83, 0x00, 0x68, 0x00, 0x00, 0x00, 0xd9, 0xfc, 0x00, 0x7c, 0xf1, 0xff, 0x83,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x65, 0x00, 0x00, 0x00, 0x64, 0x03, 0xe8, 0x00, 0x64, 0x00, 0x28,
    0x00, 0x00, 0x00, 0x25, 0x00, 0x00, 0x00, 0x00, 0x16, 0xa0, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
    0x00, 0x00, 0x10, 0x00, 0x00, 0x2f, 0x00, 0x00, 0x00, 0x00, 0x01, 0xf4, 0x00, 0x00, 0x10, 0x00,
    /* bank # 2 */
    0x00, 0x28, 0x00, 0x00, 0xff, 0xff, 0x45, 0x81, 0xff, 0xff, 0xfa, 0x72, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x00, 0x05, 0x00, 0x05, 0xba, 0xc6, 0x00, 0x47, 0x78, 0xa2,
    0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x00, 0x00, 0x00, 0x00, 0x14,
    0x00, 0x00, 0x25, 0x4d, 0x00, 0x2f, 0x70, 0x6d, 0x00, 0x00, 0x05, 0xae, 0x00, 0x0c, 0x02, 0xd0,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x1b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x64, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x1b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x0e,
    0x00, 0x00, 0x0a, 0xc7, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x32, 0xff, 0xff, 0xff, 0x9c,
    0x00, 0x00, 0x0b, 0x2b, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x64,
    0xff, 0xe5, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    /* bank # 3 */
    0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x01, 0x80, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x24, 0x26, 0xd3,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x00, 0x10, 0x00, 0x96, 0x00, 0x3c,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x0c, 0x0a, 0x4e, 0x68, 0xcd, 0xcf, 0x77, 0x09, 0x50, 0x16, 0x67, 0x59, 0xc6, 0x19, 0xce, 0x82,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x17, 0xd7, 0x84, 0x00, 0x03, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc7, 0x93, 0x8f, 0x9d, 0x1e, 0x1b, 0x1c, 0x19,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x03, 0x18, 0x85, 0x00, 0x00, 0x40, 0x00,
    0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x67, 0x7d, 0xdf, 0x7e, 0x72, 0x90, 0x2e, 0x55, 0x4c, 0xf6, 0xe6, 0x88,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,

    /* bank # 4 */
    0xd8, 0xdc, 0xb4, 0xb8, 0xb0, 0xd8, 0xb9, 0xab, 0xf3, 0xf8, 0xfa, 0xb3, 0xb7, 0xbb, 0x8e, 0x9e,
    0xae, 0xf1, 0x32, 0xf5, 0x1b, 0xf1, 0xb4, 0xb8, 0xb0, 0x80, 0x97, 0xf1, 0xa9, 0xdf, 0xdf, 0xdf,
    0xaa, 0xdf, 0xdf, 0xdf, 0xf2, 0xaa, 0xc5, 0xcd, 0xc7, 0xa9, 0x0c, 0xc9, 0x2c, 0x97, 0xf1, 0xa9,
    0x89, 0x26, 0x46, 0x66, 0xb2, 0x89, 0x99, 0xa9, 0x2d, 0x55, 0x7d, 0xb0, 0xb0, 0x8a, 0xa8, 0x96,
    0x36, 0x56, 0x76, 0xf1, 0xba, 0xa3, 0xb4, 0xb2, 0x80, 0xc0, 0xb8, 0xa8, 0x97, 0x11, 0xb2, 0x83,
    0x98, 0xba, 0xa3, 0xf0, 0x24, 0x08, 0x44, 0x10, 0x64, 0x18, 0xb2, 0xb9, 0xb4, 0x98, 0x83, 0xf1,
    0xa3, 0x29, 0x55, 0x7d, 0xba, 0xb5, 0xb1, 0xa3, 0x83, 0x93, 0xf0, 0x00, 0x28, 0x50, 0xf5, 0xb2,
    0xb6, 0xaa, 0x83, 0x93, 0x28, 0x54, 0x7c, 0xf1, 0xb9, 0xa3, 0x82, 0x93, 0x61, 0xba, 0xa2, 0xda,
    0xde, 0xdf, 0xdb, 0x81, 0x9a, 0xb9, 0xae, 0xf5, 0x60, 0x68, 0x70, 0xf1, 0xda, 0xba, 0xa2, 0xdf,
    0xd9, 0xba, 0xa2, 0xfa, 0xb9, 0xa3, 0x82, 0x92, 0xdb, 0x31, 0xba, 0xa2, 0xd9, 0xba, 0xa2, 0xf8,
    0xdf, 0x85, 0xa4, 0xd0, 0xc1, 0xbb, 0xad, 0x83, 0xc2, 0xc5, 0xc7, 0xb8, 0xa2, 0xdf, 0xdf, 0xdf,
    0xba, 0xa0, 0xdf, 0xdf, 0xdf, 0xd8, 0xd8, 0xf1, 0xb8, 0xaa, 0xb3, 0x8d, 0xb4, 0x98, 0x0d, 0x35,
    0x5d, 0xb2, 0xb6, 0xba, 0xaf, 0x8c, 0x96, 0x19, 0x8f, 0x9f, 0xa7, 0x0e, 0x16, 0x1e, 0xb4, 0x9a,
    0xb8, 0xaa, 0x87, 0x2c, 0x54, 0x7c, 0xba, 0xa4, 0xb0, 0x8a, 0xb6, 0x91, 0x32, 0x56, 0x76, 0xb2,
    0x84, 0x94, 0xa4, 0xc8, 0x08, 0xcd, 0xd8, 0xb8, 0xb4, 0xb0, 0xf1, 0x99, 0x82, 0xa8, 0x2d, 0x55,
    0x7d, 0x98, 0xa8, 0x0e, 0x16, 0x1e, 0xa2, 0x2c, 0x54, 0x7c, 0x92, 0xa4, 0xf0, 0x2c, 0x50, 0x78,
    /* bank # 5 */
    0xf1, 0x84, 0xa8, 0x98, 0xc4, 0xcd, 0xfc, 0xd8, 0x0d, 0xdb, 0xa8, 0xfc, 0x2d, 0xf3, 0xd9, 0xba,
    0xa6, 0xf8, 0xda, 0xba, 0xa6, 0xde, 0xd8, 0xba, 0xb2, 0xb6, 0x86, 0x96, 0xa6, 0xd0, 0xf3, 0xc8,
    0x41, 0xda, 0xa6, 0xc8, 0xf8, 0xd8, 0xb0, 0xb4, 0xb8, 0x82, 0xa8, 0x92, 0xf5, 0x2c, 0x54, 0x88,
    0x98, 0xf1, 0x35, 0xd9, 0xf4, 0x18, 0xd8, 0xf1, 0xa2, 0xd0, 0xf8, 0xf9, 0xa8, 0x84, 0xd9, 0xc7,
    0xdf, 0xf8, 0xf8, 0x83, 0xc5, 0xda, 0xdf, 0x69, 0xdf, 0x83, 0xc1, 0xd8, 0xf4, 0x01, 0x14, 0xf1,
    0xa8, 0x82, 0x4e, 0xa8, 0x84, 0xf3, 0x11, 0xd1, 0x82, 0xf5, 0xd9, 0x92, 0x28, 0x97, 0x88, 0xf1,
    0x09, 0xf4, 0x1c, 0x1c, 0xd8, 0x84, 0xa8, 0xf3, 0xc0, 0xf9, 0xd1, 0xd9, 0x97, 0x82, 0xf1, 0x29,
    0xf4, 0x0d, 0xd8, 0xf3, 0xf9, 0xf9, 0xd1, 0xd9, 0x82, 0xf4, 0xc2, 0x03, 0xd8, 0xde, 0xdf, 0x1a,
    0xd8, 0xf1, 0xa2, 0xfa, 0xf9, 0xa8, 0x84, 0x98, 0xd9, 0xc7, 0xdf, 0xf8, 0xf8, 0xf8, 0x83, 0xc7,
    0xda, 0xdf, 0x69, 0xdf, 0xf8, 0x83, 0xc3, 0xd8, 0xf4, 0x01, 0x14, 0xf1, 0x98, 0xa8, 0x82, 0x2e,
    0xa8, 0x84, 0xf3, 0x11, 0xd1, 0x82, 0xf5, 0xd9, 0x92, 0x50, 0x97, 0x88, 0xf1, 0x09, 0xf4, 0x1c,
    0xd8, 0x84, 0xa8, 0xf3, 0xc0, 0xf8, 0xf9, 0xd1, 0xd9, 0x97, 0x82, 0xf1, 0x49, 0xf4, 0x0d, 0xd8,
    0xf3, 0xf9, 0xf9, 0xd1, 0xd9, 0x82, 0xf4, 0xc4, 0x03, 0xd8, 0xde, 0xdf, 0xd8, 0xf1, 0xad, 0x88,
    0x98, 0xcc, 0xa8, 0x09, 0xf9, 0xd9, 0x82, 0x92, 0xa8, 0xf5, 0x7c, 0xf1, 0x88, 0x3a, 0xcf, 0x94,
    0x4a, 0x6e, 0x98, 0xdb, 0x69, 0x31, 0xda, 0xad, 0xf2, 0xde, 0xf9, 0xd8, 0x87, 0x95, 0xa8, 0xf2,
    0x21, 0xd1, 0xda, 0xa5, 0xf9, 0xf4, 0x17, 0xd9, 0xf1, 0xae, 0x8e, 0xd0, 0xc0, 0xc3, 0xae, 0x82,
    /* bank # 6 */
    0xc6, 0x84, 0xc3, 0xa8, 0x85, 0x95, 0xc8, 0xa5, 0x88, 0xf2, 0xc0, 0xf1, 0xf4, 0x01, 0x0e, 0xf1,
    0x8e, 0x9e, 0xa8, 0xc6, 0x3e, 0x56, 0xf5, 0x54, 0xf1, 0x88, 0x72, 0xf4, 0x01, 0x15, 0xf1, 0x98,
    0x45, 0x85, 0x6e, 0xf5, 0x8e, 0x9e, 0x04, 0x88, 0xf1, 0x42, 0x98, 0x5a, 0x8e, 0x9e, 0x06, 0x88,
    0x69, 0xf4, 0x01, 0x1c, 0xf1, 0x98, 0x1e, 0x11, 0x08, 0xd0, 0xf5, 0x04, 0xf1, 0x1e, 0x97, 0x02,
    0x02, 0x98, 0x36, 0x25, 0xdb, 0xf9, 0xd9, 0x85, 0xa5, 0xf3, 0xc1, 0xda, 0x85, 0xa5, 0xf3, 0xdf,
    0xd8, 0x85, 0x95, 0xa8, 0xf3, 0x09, 0xda, 0xa5, 0xfa, 0xd8, 0x82, 0x92, 0xa8, 0xf5, 0x78, 0xf1,
    0x88, 0x1a, 0x84, 0x9f, 0x26, 0x88, 0x98, 0x21, 0xda, 0xf4, 0x1d, 0xf3, 0xd8, 0x87, 0x9f, 0x39,
    0xd1, 0xaf, 0xd9, 0xdf, 0xdf, 0xfb, 0xf9, 0xf4, 0x0c, 0xf3, 0xd8, 0xfa, 0xd0, 0xf8, 0xda, 0xf9,
    0xf9, 0xd0, 0xdf, 0xd9, 0xf9, 0xd8, 0xf4, 0x0b, 0xd8, 0xf3, 0x87, 0x9f, 0x39, 0xd1, 0xaf, 0xd9,
    0xdf, 0xdf, 0xf4, 0x1d, 0xf3, 0xd8, 0xfa, 0xfc, 0xa8, 0x69, 0xf9, 0xf9, 0xaf, 0xd0, 0xda, 0xde,
    0xfa, 0xd9, 0xf8, 0x8f, 0x9f, 0xa8, 0xf1, 0xcc, 0xf3, 0x98, 0xdb, 0x45, 0xd9, 0xaf, 0xdf, 0xd0,
    0xf8, 0xd8, 0xf1, 0x8f, 0x9f, 0xa8, 0xca, 0xf3, 0x88, 0x09, 0xda, 0xaf, 0x8f, 0xcb, 0xf8, 0xd8,
    0xf2, 0xad, 0x97, 0x8d, 0x0c, 0xd9, 0xa5, 0xdf, 0xf9, 0xba, 0xa6, 0xf3, 0xfa, 0xf4, 0x12, 0xf2,
    0xd8, 0x95, 0x0d, 0xd1, 0xd9, 0xba, 0xa6, 0xf3, 0xfa, 0xda, 0xa5, 0xf2, 0xc1, 0xba, 0xa6, 0xf3,
    0xdf, 0xd8, 0xf1, 0xba, 0xb2, 0xb6, 0x86, 0x96, 0xa6, 0xd0, 0xca, 0xf3, 0x49, 0xda, 0xa6, 0xcb,
    0xf8, 0xd8, 0xb0, 0xb4, 0xb8, 0xd8, 0xad, 0x84, 0xf2, 0xc0, 0xdf, 0xf1, 0x8f, 0xcb, 0xc3, 0xa8,
    /* bank # 7 */
    0xb2, 0xb6, 0x86, 0x96, 0xc8, 0xc1, 0xcb, 0xc3, 0xf3, 0xb0, 0xb4, 0x88, 0x98, 0xa8, 0x21, 0xdb,
    0x71, 0x8d, 0x9d, 0x71, 0x85, 0x95, 0x21, 0xd9, 0xad, 0xf2, 0xfa, 0xd8, 0x85, 0x97, 0xa8, 0x28,
    0xd9, 0xf4, 0x08, 0xd8, 0xf2, 0x8d, 0x29, 0xda, 0xf4, 0x05, 0xd9, 0xf2, 0x85, 0xa4, 0xc2, 0xf2,
    0xd8, 0xa8, 0x8d, 0x94, 0x01, 0xd1, 0xd9, 0xf4, 0x11, 0xf2, 0xd8, 0x87, 0x21, 0xd8, 0xf4, 0x0a,
    0xd8, 0xf2, 0x84, 0x98, 0xa8, 0xc8, 0x01, 0xd1, 0xd9, 0xf4, 0x11, 0xd8, 0xf3, 0xa4, 0xc8, 0xbb,
    0xaf, 0xd0, 0xf2, 0xde, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xd8, 0xf1, 0xb8, 0xf6,
    0xb5, 0xb9, 0xb0, 0x8a, 0x95, 0xa3, 0xde, 0x3c, 0xa3, 0xd9, 0xf8, 0xd8, 0x5c, 0xa3, 0xd9, 0xf8,
    0xd8, 0x7c, 0xa3, 0xd9, 0xf8, 0xd8, 0xf8, 0xf9, 0xd1, 0xa5, 0xd9, 0xdf, 0xda, 0xfa, 0xd8, 0xb1,
    0x85, 0x30, 0xf7, 0xd9, 0xde, 0xd8, 0xf8, 0x30, 0xad, 0xda, 0xde, 0xd8, 0xf2, 0xb4, 0x8c, 0x99,
    0xa3, 0x2d, 0x55, 0x7d, 0xa0, 0x83, 0xdf, 0xdf, 0xdf, 0xb5, 0x91, 0xa0, 0xf6, 0x29, 0xd9, 0xfb,
    0xd8, 0xa0, 0xfc, 0x29, 0xd9, 0xfa, 0xd8, 0xa0, 0xd0, 0x51, 0xd9, 0xf8, 0xd8, 0xfc, 0x51, 0xd9,
    0xf9, 0xd8, 0x79, 0xd9, 0xfb, 0xd8, 0xa0, 0xd0, 0xfc, 0x79, 0xd9, 0xfa, 0xd8, 0xa1, 0xf9, 0xf9,
    0xf9, 0xf9, 0xf9, 0xa0, 0xda, 0xdf, 0xdf, 0xdf, 0xd8, 0xa1, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xac,
    0xde, 0xf8, 0xad, 0xde, 0x83, 0x93, 0xac, 0x2c, 0x54, 0x7c, 0xf1, 0xa8, 0xdf, 0xdf, 0xdf, 0xf6,
    0x9d, 0x2c, 0xda, 0xa0, 0xdf, 0xd9, 0xfa, 0xdb, 0x2d, 0xf8, 0xd8, 0xa8, 0x50, 0xda, 0xa0, 0xd0,
    0xde, 0xd9, 0xd0, 0xf8, 0xf8, 0xf8, 0xdb, 0x55, 0xf8, 0xd8, 0xa8, 0x78, 0xda, 0xa0, 0xd0, 0xdf,
    /* bank # 8 */
    0xd9, 0xd0, 0xfa, 0xf8, 0xf8, 0xf8, 0xf8, 0xdb, 0x7d, 0xf8, 0xd8, 0x9c, 0xa8, 0x8c, 0xf5, 0x30,
    0xdb, 0x38, 0xd9, 0xd0, 0xde, 0xdf, 0xa0, 0xd0, 0xde, 0xdf, 0xd8, 0xa8, 0x48, 0xdb, 0x58, 0xd9,
    0xdf, 0xd0, 0xde, 0xa0, 0xdf, 0xd0, 0xde, 0xd8, 0xa8, 0x68, 0xdb, 0x70, 0xd9, 0xdf, 0xdf, 0xa0,
    0xdf, 0xdf, 0xd8, 0xf1, 0xa8, 0x88, 0x90, 0x2c, 0x54, 0x7c, 0x98, 0xa8, 0xd0, 0x5c, 0x38, 0xd1,
    0xda, 0xf2, 0xae, 0x8c, 0xdf, 0xf9, 0xd8, 0xb0, 0x87, 0xa8, 0xc1, 0xc1, 0xb1, 0x88, 0xa8, 0xc6,
    0xf9, 0xf9, 0xda, 0x36, 0xd8, 0xa8, 0xf9, 0xda, 0x36, 0xd8, 0xa8, 0xf9, 0xda, 0x36, 0xd8, 0xa8,
    0xf9, 0xda, 0x36, 0xd8, 0xa8, 0xf9, 0xda, 0x36, 0xd8, 0xf7, 0x8d, 0x9d, 0xad, 0xf8, 0x18, 0xda,
    0xf2, 0xae, 0xdf, 0xd8, 0xf7, 0xad, 0xfa, 0x30, 0xd9, 0xa4, 0xde, 0xf9, 0xd8, 0xf2, 0xae, 0xde,
    0xfa, 0xf9, 0x83, 0xa7, 0xd9, 0xc3, 0xc5, 0xc7, 0xf1, 0x88, 0x9b, 0xa7, 0x7a, 0xad, 0xf7, 0xde,
    0xdf, 0xa4, 0xf8, 0x84, 0x94, 0x08, 0xa7, 0x97, 0xf3, 0x00, 0xae, 0xf2, 0x98, 0x19, 0xa4, 0x88,
    0xc6, 0xa3, 0x94, 0x88, 0xf6, 0x32, 0xdf, 0xf2, 0x83, 0x93, 0xdb, 0x09, 0xd9, 0xf2, 0xaa, 0xdf,
    0xd8, 0xd8, 0xae, 0xf8, 0xf9, 0xd1, 0xda, 0xf3, 0xa4, 0xde, 0xa7, 0xf1, 0x88, 0x9b, 0x7a, 0xd8,
    0xf3, 0x84, 0x94, 0xae, 0x19, 0xf9, 0xda, 0xaa, 0xf1, 0xdf, 0xd8, 0xa8, 0x81, 0xc0, 0xc3, 0xc5,
    0xc7, 0xa3, 0x92, 0x83, 0xf6, 0x28, 0xad, 0xde, 0xd9, 0xf8, 0xd8, 0xa3, 0x50, 0xad, 0xd9, 0xf8,
    0xd8, 0xa3, 0x78, 0xad, 0xd9, 0xf8, 0xd8, 0xf8, 0xf9, 0xd1, 0xa1, 0xda, 0xde, 0xc3, 0xc5, 0xc7,
    0xd8, 0xa1, 0x81, 0x94, 0xf8, 0x18, 0xf2, 0xb0, 0x89, 0xac, 0xc3, 0xc5, 0xc7, 0xf1, 0xd8, 0xb8,
    /* bank # 9 */
    0xb4, 0xb0, 0x97, 0x86, 0xa8, 0x31, 0x9b, 0x06, 0x99, 0x07, 0xab, 0x97, 0x28, 0x88, 0x9b, 0xf0,
    0x0c, 0x20, 0x14, 0x40, 0xb0, 0xb4, 0xb8, 0xf0, 0xa8, 0x8a, 0x9a, 0x28, 0x50, 0x78, 0xb7, 0x9b,
    0xa8, 0x29, 0x51, 0x79, 0x24, 0x70, 0x59, 0x44, 0x69, 0x38, 0x64, 0x48, 0x31, 0xf1, 0xbb, 0xab,
    0x88, 0x00, 0x2c, 0x54, 0x7c, 0xf0, 0xb3, 0x8b, 0xb8, 0xa8, 0x04, 0x28, 0x50, 0x78, 0xf1, 0xb0,
    0x88, 0xb4, 0x97, 0x26, 0xa8, 0x59, 0x98, 0xbb, 0xab, 0xb3, 0x8b, 0x02, 0x26, 0x46, 0x66, 0xb0,
    0xb8, 0xf0, 0x8a, 0x9c, 0xa8, 0x29, 0x51, 0x79, 0x8b, 0x29, 0x51, 0x79, 0x8a, 0x24, 0x70, 0x59,
    0x8b, 0x20, 0x58, 0x71, 0x8a, 0x44, 0x69, 0x38, 0x8b, 0x39, 0x40, 0x68, 0x8a, 0x64, 0x48, 0x31,
    0x8b, 0x30, 0x49, 0x60, 0x88, 0xf1, 0xac, 0x00, 0x2c, 0x54, 0x7c, 0xf0, 0x8c, 0xa8, 0x04, 0x28,
    0x50, 0x78, 0xf1, 0x88, 0x97, 0x26, 0xa8, 0x59, 0x98, 0xac, 0x8c, 0x02, 0x26, 0x46, 0x66, 0xf0,
    0x89, 0x9c, 0xa8, 0x29, 0x51, 0x79, 0x24, 0x70, 0x59, 0x44, 0x69, 0x38, 0x64, 0x48, 0x31, 0xa9,
    0x88, 0x09, 0x20, 0x59, 0x70, 0xab, 0x11, 0x38, 0x40, 0x69, 0xa8, 0x19, 0x31, 0x48, 0x60, 0x8c,
    0xa8, 0x3c, 0x41, 0x5c, 0x20, 0x7c, 0x00, 0xf1, 0x87, 0x98, 0x19, 0x86, 0xa8, 0x6e, 0x76, 0x7e,
    0xa9, 0x99, 0x88, 0x2d, 0x55, 0x7d, 0xd8, 0xb1, 0xb5, 0xb9, 0xa3, 0xdf, 0xdf, 0xdf, 0xae, 0xd0,
    0xdf, 0xaa, 0xd0, 0xde, 0xf2, 0xab, 0xf8, 0xf9, 0xd9, 0xb0, 0x87, 0xc4, 0xaa, 0xf1, 0xdf, 0xdf,
    0xbb, 0xaf, 0xdf, 0xdf, 0xb9, 0xd8, 0xb1, 0xf1, 0xa3, 0x97, 0x8e, 0x60, 0xdf, 0xb0, 0x84, 0xf2,
    0xc8, 0xf8, 0xf9, 0xd9, 0xde, 0xd8, 0x93, 0x85, 0xf1, 0x4a, 0xb1, 0x83, 0xa3, 0x08, 0xb5, 0x83,
    /* bank # 10 */
    0x9a, 0x08, 0x10, 0xb7, 0x9f, 0x10, 0xd8, 0xf1, 0xb0, 0xba, 0xae, 0xb0, 0x8a, 0xc2, 0xb2, 0xb6,
    0x8e, 0x9e, 0xf1, 0xfb, 0xd9, 0xf4, 0x1d, 0xd8, 0xf9, 0xd9, 0x0c, 0xf1, 0xd8, 0xf8, 0xf8, 0xad,
    0x61, 0xd9, 0xae, 0xfb, 0xd8, 0xf4, 0x0c, 0xf1, 0xd8, 0xf8, 0xf8, 0xad, 0x19, 0xd9, 0xae, 0xfb,
    0xdf, 0xd8, 0xf4, 0x16, 0xf1, 0xd8, 0xf8, 0xad, 0x8d, 0x61, 0xd9, 0xf4, 0xf4, 0xac, 0xf5, 0x9c,
    0x9c, 0x8d, 0xdf, 0x2b, 0xba, 0xb6, 0xae, 0xfa, 0xf8, 0xf4, 0x0b, 0xd8, 0xf1, 0xae, 0xd0, 0xf8,
    0xad, 0x51, 0xda, 0xae, 0xfa, 0xf8, 0xf1, 0xd8, 0xb9, 0xb1, 0xb6, 0xa3, 0x83, 0x9c, 0x08, 0xb9,
    0xb1, 0x83, 0x9a, 0xb5, 0xaa, 0xc0, 0xfd, 0x30, 0x83, 0xb7, 0x9f, 0x10, 0xb5, 0x8b, 0x93, 0xf2,
    0x02, 0x02, 0xd1, 0xab, 0xda, 0xde, 0xd8, 0xf1, 0xb0, 0x80, 0xba, 0xab, 0xc0, 0xc3, 0xb2, 0x84,
    0xc1, 0xc3, 0xd8, 0xb1, 0xb9, 0xf3, 0x8b, 0xa3, 0x91, 0xb6, 0x09, 0xb4, 0xd9, 0xab, 0xde, 0xb0,
    0x87, 0x9c, 0xb9, 0xa3, 0xdd, 0xf1, 0xb3, 0x8b, 0x8b, 0x8b, 0x8b, 0x8b, 0xb0, 0x87, 0xa3, 0xa3,
    0xa3, 0xa3, 0xb2, 0x8b, 0xb6, 0x9b, 0xf2, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3,
    0xa3, 0xf1, 0xb0, 0x87, 0xb5, 0x9a, 0xa3, 0xf3, 0x9b, 0xa3, 0xa3, 0xdc, 0xba, 0xac, 0xdf, 0xb9,
    0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3, 0xa3,
    0xd8, 0xd8, 0xd8, 0xbb, 0xb3, 0xb7, 0xf1, 0xaa, 0xf9, 0xda, 0xff, 0xd9, 0x80, 0x9a, 0xaa, 0x28,
    0xb4, 0x80, 0x98, 0xa7, 0x20, 0xb7, 0x97, 0x87, 0xa8, 0x66, 0x88, 0xf0, 0x79, 0x51, 0xf1, 0x90,
    0x2c, 0x87, 0x0c, 0xa7, 0x81, 0x97, 0x62, 0x93, 0xf0, 0x71, 0x71, 0x60, 0x85, 0x94, 0x01, 0x29,
    /* bank # 11 */
    0x51, 0x79, 0x90, 0xa5, 0xf1, 0x28, 0x4c, 0x6c, 0x87, 0x0c, 0x95, 0x18, 0x85, 0x78, 0xa3, 0x83,
    0x90, 0x28, 0x4c, 0x6c, 0x88, 0x6c, 0xd8, 0xf3, 0xa2, 0x82, 0x00, 0xf2, 0x10, 0xa8, 0x92, 0x19,
    0x80, 0xa2, 0xf2, 0xd9, 0x26, 0xd8, 0xf1, 0x88, 0xa8, 0x4d, 0xd9, 0x48, 0xd8, 0x96, 0xa8, 0x39,
    0x80, 0xd9, 0x3c, 0xd8, 0x95, 0x80, 0xa8, 0x39, 0xa6, 0x86, 0x98, 0xd9, 0x2c, 0xda, 0x87, 0xa7,
    0x2c, 0xd8, 0xa8, 0x89, 0x95, 0x19, 0xa9, 0x80, 0xd9, 0x38, 0xd8, 0xa8, 0x89, 0x39, 0xa9, 0x80,
    0xda, 0x3c, 0xd8, 0xa8, 0x2e, 0xa8, 0x39, 0x90, 0xd9, 0x0c, 0xd8, 0xa8, 0x95, 0x31, 0x98, 0xd9,
    0x0c, 0xd8, 0xa8, 0x09, 0xd9, 0xff, 0xd8, 0x01, 0xda, 0xff, 0xd8, 0x95, 0x39, 0xa9, 0xda, 0x26,
    0xff, 0xd8, 0x90, 0xa8, 0x0d, 0x89, 0x99, 0xa8, 0x10, 0x80, 0x98, 0x21, 0xda, 0x2e, 0xd8, 0x89,
    0x99, 0xa8, 0x31, 0x80, 0xda, 0x2e, 0xd8, 0xa8, 0x86, 0x96, 0x31, 0x80, 0xda, 0x2e, 0xd8, 0xa8,
    0x87, 0x31, 0x80, 0xda, 0x2e, 0xd8, 0xa8, 0x82, 0x92, 0xf3, 0x41, 0x80, 0xf1, 0xd9, 0x2e, 0xd8,
    0xa8, 0x82, 0xf3, 0x19, 0x80, 0xf1, 0xd9, 0x2e, 0xd8, 0x82, 0xac, 0xf3, 0xc0, 0xa2, 0x80, 0x22,
    0xf1, 0xa6, 0x2e, 0xa7, 0x2e, 0xa9, 0x22, 0x98, 0xa8, 0x29, 0xda, 0xac, 0xde, 0xff, 0xd8, 0xa2,
    0xf2, 0x2a, 0xf1, 0xa9, 0x2e, 0x82, 0x92, 0xa8, 0xf2, 0x31, 0x80, 0xa6, 0x96, 0xf1, 0xd9, 0x00,
    0xac, 0x8c, 0x9c, 0x0c, 0x30, 0xac, 0xde, 0xd0, 0xde, 0xff, 0xd8, 0x8c, 0x9c, 0xac, 0xd0, 0x10,
    0xac, 0xde, 0x80, 0x92, 0xa2, 0xf2, 0x4c, 0x82, 0xa8, 0xf1, 0xca, 0xf2, 0x35, 0xf1, 0x96, 0x88,
    0xa6, 0xd9, 0x00, 0xd8, 0xf1, 0xff
};

static const unsigned short sStartAddress = 0x0400;

/* END OF SECTION COPIED FROM dmpDefaultMPU6050.c */

#define INT_SRC_TAP             (0x01)
#define INT_SRC_ANDROID_ORIENT  (0x08)

#define DMP_FEATURE_SEND_ANY_GYRO   (DMP_FEATURE_SEND_RAW_GYRO | \
                                     DMP_FEATURE_SEND_CAL_GYRO)

#define MAX_PACKET_LENGTH_2   (32)  //前面已经有一个定义了你,避免冲突改成2

#define DMP_SAMPLE_RATE     (200)
#define GYRO_SF             (46850825LL * 200 / DMP_SAMPLE_RATE)

#define FIFO_CORRUPTION_CHECK
#ifdef FIFO_CORRUPTION_CHECK
#define QUAT_ERROR_THRESH       (1L<<24)
#define QUAT_MAG_SQ_NORMALIZED  (1L<<28)
#define QUAT_MAG_SQ_MIN         (QUAT_MAG_SQ_NORMALIZED - QUAT_ERROR_THRESH)
#define QUAT_MAG_SQ_MAX         (QUAT_MAG_SQ_NORMALIZED + QUAT_ERROR_THRESH)
#endif

struct dmp_s {
    void (*tap_cb)(unsigned char count, unsigned char direction);
    void (*android_orient_cb)(unsigned char orientation);
    unsigned short orient;
    unsigned short feature_mask;
    unsigned short fifo_rate;
    unsigned char packet_length;
};

//static struct dmp_s dmp = {
//    .tap_cb = NULL,
//    .android_orient_cb = NULL,
//    .orient = 0,
//    .feature_mask = 0,
//    .fifo_rate = 0,
//    .packet_length = 0
//};

static struct dmp_s dmp={
  NULL,
  NULL,
  0,
  0,
  0,
  0
};

/**
 *  @brief  Load the DMP with this image.
 *  @return 0 if successful.
 */
int dmp_load_motion_driver_firmware(void)
{
    return mpu_load_firmware(DMP_CODE_SIZE, dmp_memory, sStartAddress,
        DMP_SAMPLE_RATE);
}

/**
 *  @brief      Push gyro and accel orientation to the DMP.
 *  The orientation is represented here as the output of
 *  @e inv_orientation_matrix_to_scalar.
 *  @param[in]  orient  Gyro and accel orientation in body frame.
 *  @return     0 if successful.
 */
int dmp_set_orientation(unsigned short orient)
{
    unsigned char gyro_regs[3], accel_regs[3];
    const unsigned char gyro_axes[3] = {DINA4C, DINACD, DINA6C};
    const unsigned char accel_axes[3] = {DINA0C, DINAC9, DINA2C};
    const unsigned char gyro_sign[3] = {DINA36, DINA56, DINA76};
    const unsigned char accel_sign[3] = {DINA26, DINA46, DINA66};

    gyro_regs[0] = gyro_axes[orient & 3];
    gyro_regs[1] = gyro_axes[(orient >> 3) & 3];
    gyro_regs[2] = gyro_axes[(orient >> 6) & 3];
    accel_regs[0] = accel_axes[orient & 3];
    accel_regs[1] = accel_axes[(orient >> 3) & 3];
    accel_regs[2] = accel_axes[(orient >> 6) & 3];

    /* Chip-to-body, axes only. */
    if (mpu_write_mem(FCFG_1, 3, gyro_regs))
        return -1;
    if (mpu_write_mem(FCFG_2, 3, accel_regs))
        return -1;

    memcpy(gyro_regs, gyro_sign, 3);
    memcpy(accel_regs, accel_sign, 3);
    if (orient & 4) {
        gyro_regs[0] |= 1;
        accel_regs[0] |= 1;
    }
    if (orient & 0x20) {
        gyro_regs[1] |= 1;
        accel_regs[1] |= 1;
    }
    if (orient & 0x100) {
        gyro_regs[2] |= 1;
        accel_regs[2] |= 1;
    }

    /* Chip-to-body, sign only. */
    if (mpu_write_mem(FCFG_3, 3, gyro_regs))
        return -1;
    if (mpu_write_mem(FCFG_7, 3, accel_regs))
        return -1;
    dmp.orient = orient;
    return 0;
}

/**
 *  @brief      Push gyro biases to the DMP.
 *  Because the gyro integration is handled in the DMP, any gyro biases
 *  calculated by the MPL should be pushed down to DMP memory to remove
 *  3-axis quaternion drift.
 *  \n NOTE: If the DMP-based gyro calibration is enabled, the DMP will
 *  overwrite the biases written to this location once a new one is computed.
 *  @param[in]  bias    Gyro biases in q16.
 *  @return     0 if successful.
 */
int dmp_set_gyro_bias(long *bias)
{
    long gyro_bias_body[3];
    unsigned char regs[4];

    gyro_bias_body[0] = bias[dmp.orient & 3];
    if (dmp.orient & 4)
        gyro_bias_body[0] *= -1;
    gyro_bias_body[1] = bias[(dmp.orient >> 3) & 3];
    if (dmp.orient & 0x20)
        gyro_bias_body[1] *= -1;
    gyro_bias_body[2] = bias[(dmp.orient >> 6) & 3];
    if (dmp.orient & 0x100)
        gyro_bias_body[2] *= -1;

#ifdef EMPL_NO_64BIT
    gyro_bias_body[0] = (long)(((float)gyro_bias_body[0] * GYRO_SF) / 1073741824.f);
    gyro_bias_body[1] = (long)(((float)gyro_bias_body[1] * GYRO_SF) / 1073741824.f);
    gyro_bias_body[2] = (long)(((float)gyro_bias_body[2] * GYRO_SF) / 1073741824.f);
#else
    gyro_bias_body[0] = (long)(((long long)gyro_bias_body[0] * GYRO_SF) >> 30);
    gyro_bias_body[1] = (long)(((long long)gyro_bias_body[1] * GYRO_SF) >> 30);
    gyro_bias_body[2] = (long)(((long long)gyro_bias_body[2] * GYRO_SF) >> 30);
#endif

    regs[0] = (unsigned char)((gyro_bias_body[0] >> 24) & 0xFF);
    regs[1] = (unsigned char)((gyro_bias_body[0] >> 16) & 0xFF);
    regs[2] = (unsigned char)((gyro_bias_body[0] >> 8) & 0xFF);
    regs[3] = (unsigned char)(gyro_bias_body[0] & 0xFF);
    if (mpu_write_mem(D_EXT_GYRO_BIAS_X, 4, regs))
        return -1;

    regs[0] = (unsigned char)((gyro_bias_body[1] >> 24) & 0xFF);
    regs[1] = (unsigned char)((gyro_bias_body[1] >> 16) & 0xFF);
    regs[2] = (unsigned char)((gyro_bias_body[1] >> 8) & 0xFF);
    regs[3] = (unsigned char)(gyro_bias_body[1] & 0xFF);
    if (mpu_write_mem(D_EXT_GYRO_BIAS_Y, 4, regs))
        return -1;

    regs[0] = (unsigned char)((gyro_bias_body[2] >> 24) & 0xFF);
    regs[1] = (unsigned char)((gyro_bias_body[2] >> 16) & 0xFF);
    regs[2] = (unsigned char)((gyro_bias_body[2] >> 8) & 0xFF);
    regs[3] = (unsigned char)(gyro_bias_body[2] & 0xFF);
    return mpu_write_mem(D_EXT_GYRO_BIAS_Z, 4, regs);
}

/**
 *  @brief      Push accel biases to the DMP.
 *  These biases will be removed from the DMP 6-axis quaternion.
 *  @param[in]  bias    Accel biases in q16.
 *  @return     0 if successful.
 */
int dmp_set_accel_bias(long *bias)
{
    long accel_bias_body[3];
    unsigned char regs[12];
    long long accel_sf;
    unsigned short accel_sens;

    mpu_get_accel_sens(&accel_sens);
    accel_sf = (long long)accel_sens << 15;
    //__no_operation();

    accel_bias_body[0] = bias[dmp.orient & 3];
    if (dmp.orient & 4)
        accel_bias_body[0] *= -1;
    accel_bias_body[1] = bias[(dmp.orient >> 3) & 3];
    if (dmp.orient & 0x20)
        accel_bias_body[1] *= -1;
    accel_bias_body[2] = bias[(dmp.orient >> 6) & 3];
    if (dmp.orient & 0x100)
        accel_bias_body[2] *= -1;

#ifdef EMPL_NO_64BIT
    accel_bias_body[0] = (long)(((float)accel_bias_body[0] * accel_sf) / 1073741824.f);
    accel_bias_body[1] = (long)(((float)accel_bias_body[1] * accel_sf) / 1073741824.f);
    accel_bias_body[2] = (long)(((float)accel_bias_body[2] * accel_sf) / 1073741824.f);
#else
    accel_bias_body[0] = (long)(((long long)accel_bias_body[0] * accel_sf) >> 30);
    accel_bias_body[1] = (long)(((long long)accel_bias_body[1] * accel_sf) >> 30);
    accel_bias_body[2] = (long)(((long long)accel_bias_body[2] * accel_sf) >> 30);
#endif

    regs[0] = (unsigned char)((accel_bias_body[0] >> 24) & 0xFF);
    regs[1] = (unsigned char)((accel_bias_body[0] >> 16) & 0xFF);
    regs[2] = (unsigned char)((accel_bias_body[0] >> 8) & 0xFF);
    regs[3] = (unsigned char)(accel_bias_body[0] & 0xFF);
    regs[4] = (unsigned char)((accel_bias_body[1] >> 24) & 0xFF);
    regs[5] = (unsigned char)((accel_bias_body[1] >> 16) & 0xFF);
    regs[6] = (unsigned char)((accel_bias_body[1] >> 8) & 0xFF);
    regs[7] = (unsigned char)(accel_bias_body[1] & 0xFF);
    regs[8] = (unsigned char)((accel_bias_body[2] >> 24) & 0xFF);
    regs[9] = (unsigned char)((accel_bias_body[2] >> 16) & 0xFF);
    regs[10] = (unsigned char)((accel_bias_body[2] >> 8) & 0xFF);
    regs[11] = (unsigned char)(accel_bias_body[2] & 0xFF);
    return mpu_write_mem(D_ACCEL_BIAS, 12, regs);
}

/**
 *  @brief      Set DMP output rate.
 *  Only used when DMP is on.
 *  @param[in]  rate    Desired fifo rate (Hz).
 *  @return     0 if successful.
 */
int dmp_set_fifo_rate(unsigned short rate)
{
    const unsigned char regs_end[12] = {DINAFE, DINAF2, DINAAB,
        0xc4, DINAAA, DINAF1, DINADF, DINADF, 0xBB, 0xAF, DINADF, DINADF};
    unsigned short div;
    unsigned char tmp[8];

    if (rate > DMP_SAMPLE_RATE)
        return -1;
    div = DMP_SAMPLE_RATE / rate - 1;
    tmp[0] = (unsigned char)((div >> 8) & 0xFF);
    tmp[1] = (unsigned char)(div & 0xFF);
    if (mpu_write_mem(D_0_22, 2, tmp))
        return -1;
    if (mpu_write_mem(CFG_6, 12, (unsigned char*)regs_end))
        return -1;

    dmp.fifo_rate = rate;
    return 0;
}

/**
 *  @brief      Get DMP output rate.
 *  @param[out] rate    Current fifo rate (Hz).
 *  @return     0 if successful.
 */
int dmp_get_fifo_rate(unsigned short *rate)
{
    rate[0] = dmp.fifo_rate;
    return 0;
}

/**
 *  @brief      Set tap threshold for a specific axis.
 *  @param[in]  axis    1, 2, and 4 for XYZ accel, respectively.
 *  @param[in]  thresh  Tap threshold, in mg/ms.
 *  @return     0 if successful.
 */
int dmp_set_tap_thresh(unsigned char axis, unsigned short thresh)
{
    unsigned char tmp[4], accel_fsr;
    float scaled_thresh;
    unsigned short dmp_thresh, dmp_thresh_2;
    if (!(axis & TAP_XYZ) || thresh > 1600)
        return -1;

    scaled_thresh = (float)thresh / DMP_SAMPLE_RATE;

    mpu_get_accel_fsr(&accel_fsr);
    switch (accel_fsr) {
    case 2:
        dmp_thresh = (unsigned short)(scaled_thresh * 16384);
        /* dmp_thresh * 0.75 */
        dmp_thresh_2 = (unsigned short)(scaled_thresh * 12288);
        break;
    case 4:
        dmp_thresh = (unsigned short)(scaled_thresh * 8192);
        /* dmp_thresh * 0.75 */
        dmp_thresh_2 = (unsigned short)(scaled_thresh * 6144);
        break;
    case 8:
        dmp_thresh = (unsigned short)(scaled_thresh * 4096);
        /* dmp_thresh * 0.75 */
        dmp_thresh_2 = (unsigned short)(scaled_thresh * 3072);
        break;
    case 16:
        dmp_thresh = (unsigned short)(scaled_thresh * 2048);
        /* dmp_thresh * 0.75 */
        dmp_thresh_2 = (unsigned short)(scaled_thresh * 1536);
        break;
    default:
        return -1;
    }
    tmp[0] = (unsigned char)(dmp_thresh >> 8);
    tmp[1] = (unsigned char)(dmp_thresh & 0xFF);
    tmp[2] = (unsigned char)(dmp_thresh_2 >> 8);
    tmp[3] = (unsigned char)(dmp_thresh_2 & 0xFF);

    if (axis & TAP_X) {
        if (mpu_write_mem(DMP_TAP_THX, 2, tmp))
            return -1;
        if (mpu_write_mem(D_1_36, 2, tmp+2))
            return -1;
    }
    if (axis & TAP_Y) {
        if (mpu_write_mem(DMP_TAP_THY, 2, tmp))
            return -1;
        if (mpu_write_mem(D_1_40, 2, tmp+2))
            return -1;
    }
    if (axis & TAP_Z) {
        if (mpu_write_mem(DMP_TAP_THZ, 2, tmp))
            return -1;
        if (mpu_write_mem(D_1_44, 2, tmp+2))
            return -1;
    }
    return 0;
}

/**
 *  @brief      Set which axes will register a tap.
 *  @param[in]  axis    1, 2, and 4 for XYZ, respectively.
 *  @return     0 if successful.
 */
int dmp_set_tap_axes(unsigned char axis)
{
    unsigned char tmp = 0;

    if (axis & TAP_X)
        tmp |= 0x30;
    if (axis & TAP_Y)
        tmp |= 0x0C;
    if (axis & TAP_Z)
        tmp |= 0x03;
    return mpu_write_mem(D_1_72, 1, &tmp);
}

/**
 *  @brief      Set minimum number of taps needed for an interrupt.
 *  @param[in]  min_taps    Minimum consecutive taps (1-4).
 *  @return     0 if successful.
 */
int dmp_set_tap_count(unsigned char min_taps)
{
    unsigned char tmp;

    if (min_taps < 1)
        min_taps = 1;
    else if (min_taps > 4)
        min_taps = 4;

    tmp = min_taps - 1;
    return mpu_write_mem(D_1_79, 1, &tmp);
}

/**
 *  @brief      Set length between valid taps.
 *  @param[in]  time    Milliseconds between taps.
 *  @return     0 if successful.
 */
int dmp_set_tap_time(unsigned short time)
{
    unsigned short dmp_time;
    unsigned char tmp[2];

    dmp_time = time / (1000 / DMP_SAMPLE_RATE);
    tmp[0] = (unsigned char)(dmp_time >> 8);
    tmp[1] = (unsigned char)(dmp_time & 0xFF);
    return mpu_write_mem(DMP_TAPW_MIN, 2, tmp);
}

/**
 *  @brief      Set max time between taps to register as a multi-tap.
 *  @param[in]  time    Max milliseconds between taps.
 *  @return     0 if successful.
 */
int dmp_set_tap_time_multi(unsigned short time)
{
    unsigned short dmp_time;
    unsigned char tmp[2];

    dmp_time = time / (1000 / DMP_SAMPLE_RATE);
    tmp[0] = (unsigned char)(dmp_time >> 8);
    tmp[1] = (unsigned char)(dmp_time & 0xFF);
    return mpu_write_mem(D_1_218, 2, tmp);
}

/**
 *  @brief      Set shake rejection threshold.
 *  If the DMP detects a gyro sample larger than @e thresh, taps are rejected.
 *  @param[in]  sf      Gyro scale factor.
 *  @param[in]  thresh  Gyro threshold in dps.
 *  @return     0 if successful.
 */
int dmp_set_shake_reject_thresh(long sf, unsigned short thresh)
{
    unsigned char tmp[4];
    long thresh_scaled = sf / 1000 * thresh;
    tmp[0] = (unsigned char)(((long)thresh_scaled >> 24) & 0xFF);
    tmp[1] = (unsigned char)(((long)thresh_scaled >> 16) & 0xFF);
    tmp[2] = (unsigned char)(((long)thresh_scaled >> 8) & 0xFF);
    tmp[3] = (unsigned char)((long)thresh_scaled & 0xFF);
    return mpu_write_mem(D_1_92, 4, tmp);
}

/**
 *  @brief      Set shake rejection time.
 *  Sets the length of time that the gyro must be outside of the threshold set
 *  by @e gyro_set_shake_reject_thresh before taps are rejected. A mandatory
 *  60 ms is added to this parameter.
 *  @param[in]  time    Time in milliseconds.
 *  @return     0 if successful.
 */
int dmp_set_shake_reject_time(unsigned short time)
{
    unsigned char tmp[2];

    time /= (1000 / DMP_SAMPLE_RATE);
    tmp[0] = time >> 8;
    tmp[1] = time & 0xFF;
    return mpu_write_mem(D_1_90,2,tmp);
}

/**
 *  @brief      Set shake rejection timeout.
 *  Sets the length of time after a shake rejection that the gyro must stay
 *  inside of the threshold before taps can be detected again. A mandatory
 *  60 ms is added to this parameter.
 *  @param[in]  time    Time in milliseconds.
 *  @return     0 if successful.
 */
int dmp_set_shake_reject_timeout(unsigned short time)
{
    unsigned char tmp[2];

    time /= (1000 / DMP_SAMPLE_RATE);
    tmp[0] = time >> 8;
    tmp[1] = time & 0xFF;
    return mpu_write_mem(D_1_88,2,tmp);
}

/**
 *  @brief      Get current step count.
 *  @param[out] count   Number of steps detected.
 *  @return     0 if successful.
 */
int dmp_get_pedometer_step_count(unsigned long *count)
{
    unsigned char tmp[4];
    if (!count)
        return -1;

    if (mpu_read_mem(D_PEDSTD_STEPCTR, 4, tmp))
        return -1;

    count[0] = ((unsigned long)tmp[0] << 24) | ((unsigned long)tmp[1] << 16) |
        ((unsigned long)tmp[2] << 8) | tmp[3];
    return 0;
}

/**
 *  @brief      Overwrite current step count.
 *  WARNING: This function writes to DMP memory and could potentially encounter
 *  a race condition if called while the pedometer is enabled.
 *  @param[in]  count   New step count.
 *  @return     0 if successful.
 */
int dmp_set_pedometer_step_count(unsigned long count)
{
    unsigned char tmp[4];

    tmp[0] = (unsigned char)((count >> 24) & 0xFF);
    tmp[1] = (unsigned char)((count >> 16) & 0xFF);
    tmp[2] = (unsigned char)((count >> 8) & 0xFF);
    tmp[3] = (unsigned char)(count & 0xFF);
    return mpu_write_mem(D_PEDSTD_STEPCTR, 4, tmp);
}

/**
 *  @brief      Get duration of walking time.
 *  @param[in]  time    Walk time in milliseconds.
 *  @return     0 if successful.
 */
int dmp_get_pedometer_walk_time(unsigned long *time)
{
    unsigned char tmp[4];
    if (!time)
        return -1;

    if (mpu_read_mem(D_PEDSTD_TIMECTR, 4, tmp))
        return -1;

    time[0] = (((unsigned long)tmp[0] << 24) | ((unsigned long)tmp[1] << 16) |
        ((unsigned long)tmp[2] << 8) | tmp[3]) * 20;
    return 0;
}

/**
 *  @brief      Overwrite current walk time.
 *  WARNING: This function writes to DMP memory and could potentially encounter
 *  a race condition if called while the pedometer is enabled.
 *  @param[in]  time    New walk time in milliseconds.
 */
int dmp_set_pedometer_walk_time(unsigned long time)
{
    unsigned char tmp[4];

    time /= 20;

    tmp[0] = (unsigned char)((time >> 24) & 0xFF);
    tmp[1] = (unsigned char)((time >> 16) & 0xFF);
    tmp[2] = (unsigned char)((time >> 8) & 0xFF);
    tmp[3] = (unsigned char)(time & 0xFF);
    return mpu_write_mem(D_PEDSTD_TIMECTR, 4, tmp);
}

/**
 *  @brief      Enable DMP features.
 *  The following \#define's are used in the input mask:
 *  \n DMP_FEATURE_TAP
 *  \n DMP_FEATURE_ANDROID_ORIENT
 *  \n DMP_FEATURE_LP_QUAT
 *  \n DMP_FEATURE_6X_LP_QUAT
 *  \n DMP_FEATURE_GYRO_CAL
 *  \n DMP_FEATURE_SEND_RAW_ACCEL
 *  \n DMP_FEATURE_SEND_RAW_GYRO
 *  \n NOTE: DMP_FEATURE_LP_QUAT and DMP_FEATURE_6X_LP_QUAT are mutually
 *  exclusive.
 *  \n NOTE: DMP_FEATURE_SEND_RAW_GYRO and DMP_FEATURE_SEND_CAL_GYRO are also
 *  mutually exclusive.
 *  @param[in]  mask    Mask of features to enable.
 *  @return     0 if successful.
 */
int dmp_enable_feature(unsigned short mask)
{
    unsigned char tmp[10];

    /* TODO: All of these settings can probably be integrated into the default
     * DMP image.
     */
    /* Set integration scale factor. */
    tmp[0] = (unsigned char)((GYRO_SF >> 24) & 0xFF);
    tmp[1] = (unsigned char)((GYRO_SF >> 16) & 0xFF);
    tmp[2] = (unsigned char)((GYRO_SF >> 8) & 0xFF);
    tmp[3] = (unsigned char)(GYRO_SF & 0xFF);
    mpu_write_mem(D_0_104, 4, tmp);

    /* Send sensor data to the FIFO. */
    tmp[0] = 0xA3;
    if (mask & DMP_FEATURE_SEND_RAW_ACCEL) {
        tmp[1] = 0xC0;
        tmp[2] = 0xC8;
        tmp[3] = 0xC2;
    } else {
        tmp[1] = 0xA3;
        tmp[2] = 0xA3;
        tmp[3] = 0xA3;
    }
    if (mask & DMP_FEATURE_SEND_ANY_GYRO) {
        tmp[4] = 0xC4;
        tmp[5] = 0xCC;
        tmp[6] = 0xC6;
    } else {
        tmp[4] = 0xA3;
        tmp[5] = 0xA3;
        tmp[6] = 0xA3;
    }
    tmp[7] = 0xA3;
    tmp[8] = 0xA3;
    tmp[9] = 0xA3;
    mpu_write_mem(CFG_15,10,tmp);

    /* Send gesture data to the FIFO. */
    if (mask & (DMP_FEATURE_TAP | DMP_FEATURE_ANDROID_ORIENT))
        tmp[0] = DINA20;
    else
        tmp[0] = 0xD8;
    mpu_write_mem(CFG_27,1,tmp);

    if (mask & DMP_FEATURE_GYRO_CAL)
        dmp_enable_gyro_cal(1);
    else
        dmp_enable_gyro_cal(0);

    if (mask & DMP_FEATURE_SEND_ANY_GYRO) {
        if (mask & DMP_FEATURE_SEND_CAL_GYRO) {
            tmp[0] = 0xB2;
            tmp[1] = 0x8B;
            tmp[2] = 0xB6;
            tmp[3] = 0x9B;
        } else {
            tmp[0] = DINAC0;
            tmp[1] = DINA80;
            tmp[2] = DINAC2;
            tmp[3] = DINA90;
        }
        mpu_write_mem(CFG_GYRO_RAW_DATA, 4, tmp);
    }

    if (mask & DMP_FEATURE_TAP) {
        /* Enable tap. */
        tmp[0] = 0xF8;
        mpu_write_mem(CFG_20, 1, tmp);
        dmp_set_tap_thresh(TAP_XYZ, 250);
        dmp_set_tap_axes(TAP_XYZ);
        dmp_set_tap_count(1);
        dmp_set_tap_time(100);
        dmp_set_tap_time_multi(500);

        dmp_set_shake_reject_thresh(GYRO_SF, 200);
        dmp_set_shake_reject_time(40);
        dmp_set_shake_reject_timeout(10);
    } else {
        tmp[0] = 0xD8;
        mpu_write_mem(CFG_20, 1, tmp);
    }

    if (mask & DMP_FEATURE_ANDROID_ORIENT) {
        tmp[0] = 0xD9;
    } else
        tmp[0] = 0xD8;
    mpu_write_mem(CFG_ANDROID_ORIENT_INT, 1, tmp);

    if (mask & DMP_FEATURE_LP_QUAT)
        dmp_enable_lp_quat(1);
    else
        dmp_enable_lp_quat(0);

    if (mask & DMP_FEATURE_6X_LP_QUAT)
        dmp_enable_6x_lp_quat(1);
    else
        dmp_enable_6x_lp_quat(0);

    /* Pedometer is always enabled. */
    dmp.feature_mask = mask | DMP_FEATURE_PEDOMETER;
    mpu_reset_fifo();

    dmp.packet_length = 0;
    if (mask & DMP_FEATURE_SEND_RAW_ACCEL)
        dmp.packet_length += 6;
    if (mask & DMP_FEATURE_SEND_ANY_GYRO)
        dmp.packet_length += 6;
    if (mask & (DMP_FEATURE_LP_QUAT | DMP_FEATURE_6X_LP_QUAT))
        dmp.packet_length += 16;
    if (mask & (DMP_FEATURE_TAP | DMP_FEATURE_ANDROID_ORIENT))
        dmp.packet_length += 4;

    return 0;
}

/**
 *  @brief      Get list of currently enabled DMP features.
 *  @param[out] Mask of enabled features.
 *  @return     0 if successful.
 */
int dmp_get_enabled_features(unsigned short *mask)
{
    mask[0] = dmp.feature_mask;
    return 0;
}

/**
 *  @brief      Calibrate the gyro data in the DMP.
 *  After eight seconds of no motion, the DMP will compute gyro biases and
 *  subtract them from the quaternion output. If @e dmp_enable_feature is
 *  called with @e DMP_FEATURE_SEND_CAL_GYRO, the biases will also be
 *  subtracted from the gyro output.
 *  @param[in]  enable  1 to enable gyro calibration.
 *  @return     0 if successful.
 */
int dmp_enable_gyro_cal(unsigned char enable)
{
    if (enable) {
        unsigned char regs[9] = {0xb8, 0xaa, 0xb3, 0x8d, 0xb4, 0x98, 0x0d, 0x35, 0x5d};
        return mpu_write_mem(CFG_MOTION_BIAS, 9, regs);
    } else {
        unsigned char regs[9] = {0xb8, 0xaa, 0xaa, 0xaa, 0xb0, 0x88, 0xc3, 0xc5, 0xc7};
        return mpu_write_mem(CFG_MOTION_BIAS, 9, regs);
    }
}

/**
 *  @brief      Generate 3-axis quaternions from the DMP.
 *  In this driver, the 3-axis and 6-axis DMP quaternion features are mutually
 *  exclusive.
 *  @param[in]  enable  1 to enable 3-axis quaternion.
 *  @return     0 if successful.
 */
int dmp_enable_lp_quat(unsigned char enable)
{
    unsigned char regs[4];
    if (enable) {
        regs[0] = DINBC0;
        regs[1] = DINBC2;
        regs[2] = DINBC4;
        regs[3] = DINBC6;
    }
    else
        memset(regs, 0x8B, 4);

    mpu_write_mem(CFG_LP_QUAT, 4, regs);

    return mpu_reset_fifo();
}

/**
 *  @brief       Generate 6-axis quaternions from the DMP.
 *  In this driver, the 3-axis and 6-axis DMP quaternion features are mutually
 *  exclusive.
 *  @param[in]   enable  1 to enable 6-axis quaternion.
 *  @return      0 if successful.
 */
int dmp_enable_6x_lp_quat(unsigned char enable)
{
    unsigned char regs[4];
    if (enable) {
        regs[0] = DINA20;
        regs[1] = DINA28;
        regs[2] = DINA30;
        regs[3] = DINA38;
    } else
        memset(regs, 0xA3, 4);

    mpu_write_mem(CFG_8, 4, regs);

    return mpu_reset_fifo();
}

/**
 *  @brief      Decode the four-byte gesture data and execute any callbacks.
 *  @param[in]  gesture Gesture data from DMP packet.
 *  @return     0 if successful.
 */
static int decode_gesture(unsigned char *gesture)
{
    unsigned char tap, android_orient;

    android_orient = gesture[3] & 0xC0;
    tap = 0x3F & gesture[3];

    if (gesture[1] & INT_SRC_TAP) {
        unsigned char direction, count;
        direction = tap >> 3;
        count = (tap % 8) + 1;
        if (dmp.tap_cb)
            dmp.tap_cb(direction, count);
    }

    if (gesture[1] & INT_SRC_ANDROID_ORIENT) {
        if (dmp.android_orient_cb)
            dmp.android_orient_cb(android_orient >> 6);
    }

    return 0;
}

/**
 *  @brief      Specify when a DMP interrupt should occur.
 *  A DMP interrupt can be configured to trigger on either of the two
 *  conditions below:
 *  \n a. One FIFO period has elapsed (set by @e mpu_set_sample_rate).
 *  \n b. A tap event has been detected.
 *  @param[in]  mode    DMP_INT_GESTURE or DMP_INT_CONTINUOUS.
 *  @return     0 if successful.
 */
int dmp_set_interrupt_mode(unsigned char mode)
{
    const unsigned char regs_continuous[11] =
        {0xd8, 0xb1, 0xb9, 0xf3, 0x8b, 0xa3, 0x91, 0xb6, 0x09, 0xb4, 0xd9};
    const unsigned char regs_gesture[11] =
        {0xda, 0xb1, 0xb9, 0xf3, 0x8b, 0xa3, 0x91, 0xb6, 0xda, 0xb4, 0xda};

    switch (mode) {
    case DMP_INT_CONTINUOUS:
        return mpu_write_mem(CFG_FIFO_ON_EVENT, 11,
            (unsigned char*)regs_continuous);
    case DMP_INT_GESTURE:
        return mpu_write_mem(CFG_FIFO_ON_EVENT, 11,
            (unsigned char*)regs_gesture);
    default:
        return -1;
    }
}

/**
 *  @brief      Get one packet from the FIFO.
 *  If @e sensors does not contain a particular sensor, disregard the data
 *  returned to that pointer.
 *  \n @e sensors can contain a combination of the following flags:
 *  \n INV_X_GYRO, INV_Y_GYRO, INV_Z_GYRO
 *  \n INV_XYZ_GYRO
 *  \n INV_XYZ_ACCEL
 *  \n INV_WXYZ_QUAT
 *  \n If the FIFO has no new data, @e sensors will be zero.
 *  \n If the FIFO is disabled, @e sensors will be zero and this function will
 *  return a non-zero error code.
 *  @param[out] gyro        Gyro data in hardware units.
 *  @param[out] accel       Accel data in hardware units.
 *  @param[out] quat        3-axis quaternion data in hardware units.
 *  @param[out] timestamp   Timestamp in milliseconds.
 *  @param[out] sensors     Mask of sensors read from FIFO.
 *  @param[out] more        Number of remaining packets.
 *  @return     0 if successful.
 */
int dmp_read_fifo(short *gyro, short *accel, long *quat,
    unsigned long *timestamp, short *sensors, unsigned char *more)
{
    unsigned char fifo_data[MAX_PACKET_LENGTH_2];
    unsigned char ii = 0;

    /* TODO: sensors[0] only changes when dmp_enable_feature is called. We can
     * cache this value and save some cycles.
     */
    sensors[0] = 0;

    /* Get a packet. */
    if (mpu_read_fifo_stream(dmp.packet_length, fifo_data, more))
        return -1;

    /* Parse DMP packet. */
    if (dmp.feature_mask & (DMP_FEATURE_LP_QUAT | DMP_FEATURE_6X_LP_QUAT)) {
#ifdef FIFO_CORRUPTION_CHECK
        long quat_q14[4], quat_mag_sq;
#endif
        quat[0] = ((long)fifo_data[0] << 24) | ((long)fifo_data[1] << 16) |
            ((long)fifo_data[2] << 8) | fifo_data[3];
        quat[1] = ((long)fifo_data[4] << 24) | ((long)fifo_data[5] << 16) |
            ((long)fifo_data[6] << 8) | fifo_data[7];
        quat[2] = ((long)fifo_data[8] << 24) | ((long)fifo_data[9] << 16) |
            ((long)fifo_data[10] << 8) | fifo_data[11];
        quat[3] = ((long)fifo_data[12] << 24) | ((long)fifo_data[13] << 16) |
            ((long)fifo_data[14] << 8) | fifo_data[15];
        ii += 16;
#ifdef FIFO_CORRUPTION_CHECK
        /* We can detect a corrupted FIFO by monitoring the quaternion data and
         * ensuring that the magnitude is always normalized to one. This
         * shouldn't happen in normal operation, but if an I2C error occurs,
         * the FIFO reads might become misaligned.
         *
         * Let's start by scaling down the quaternion data to avoid long long
         * math.
         */
        quat_q14[0] = quat[0] >> 16;
        quat_q14[1] = quat[1] >> 16;
        quat_q14[2] = quat[2] >> 16;
        quat_q14[3] = quat[3] >> 16;
        quat_mag_sq = quat_q14[0] * quat_q14[0] + quat_q14[1] * quat_q14[1] +
            quat_q14[2] * quat_q14[2] + quat_q14[3] * quat_q14[3];
        if ((quat_mag_sq < QUAT_MAG_SQ_MIN) ||
            (quat_mag_sq > QUAT_MAG_SQ_MAX)) {
            /* Quaternion is outside of the acceptable threshold. */
            mpu_reset_fifo();
            sensors[0] = 0;
            return -1;
        }
        sensors[0] |= INV_WXYZ_QUAT;
#endif
    }

    if (dmp.feature_mask & DMP_FEATURE_SEND_RAW_ACCEL) {
        accel[0] = ((short)fifo_data[ii+0] << 8) | fifo_data[ii+1];
        accel[1] = ((short)fifo_data[ii+2] << 8) | fifo_data[ii+3];
        accel[2] = ((short)fifo_data[ii+4] << 8) | fifo_data[ii+5];
        ii += 6;
        sensors[0] |= INV_XYZ_ACCEL;
    }

    if (dmp.feature_mask & DMP_FEATURE_SEND_ANY_GYRO) {
        gyro[0] = ((short)fifo_data[ii+0] << 8) | fifo_data[ii+1];
        gyro[1] = ((short)fifo_data[ii+2] << 8) | fifo_data[ii+3];
        gyro[2] = ((short)fifo_data[ii+4] << 8) | fifo_data[ii+5];
        ii += 6;
        sensors[0] |= INV_XYZ_GYRO;
    }

    /* Gesture data is at the end of the DMP packet. Parse it and call
     * the gesture callbacks (if registered).
     */
    if (dmp.feature_mask & (DMP_FEATURE_TAP | DMP_FEATURE_ANDROID_ORIENT))
        decode_gesture(fifo_data + ii);

    get_ms(timestamp);
    return 0;
}

/**
 *  @brief      Register a function to be executed on a tap event.
 *  The tap direction is represented by one of the following:
 *  \n TAP_X_UP
 *  \n TAP_X_DOWN
 *  \n TAP_Y_UP
 *  \n TAP_Y_DOWN
 *  \n TAP_Z_UP
 *  \n TAP_Z_DOWN
 *  @param[in]  func    Callback function.
 *  @return     0 if successful.
 */
int dmp_register_tap_cb(void (*func)(unsigned char, unsigned char))
{
    dmp.tap_cb = func;
    return 0;
}

/**
 *  @brief      Register a function to be executed on a android orientation event.
 *  @param[in]  func    Callback function.
 *  @return     0 if successful.
 */
int dmp_register_android_orient_cb(void (*func)(unsigned char))
{
    dmp.android_orient_cb = func;
    return 0;
}