/************************************************************/
//檔名：mpu6050.c
//功能:測試linux下iic讀寫mpu6050程式
//使用說明: (1)
//          (2)
//          (3)
//          (4)
//作者:huangea
//日期:2016-10-03
/************************************************************/
 
//包含標頭檔案
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<sys/ioctl.h>
#include<sys/types.h>
#include<sys/stat.h>
#include<fcntl.h>
#include<sys/select.h>
#include<sys/time.h>
#include<errno.h>
 
//巨集定義
 
#define	SMPLRT_DIV	0x19	
#define	CONFIG	0x1A	
#define	GYRO_CONFIG	0x1B	
#define	ACCEL_CONFIG	0x1C
#define	ACCEL_XOUT_H	0x3B
#define	ACCEL_XOUT_L	0x3C
#define	ACCEL_YOUT_H	0x3D
#define	ACCEL_YOUT_L	0x3E
#define	ACCEL_ZOUT_H	0x3F
#define	ACCEL_ZOUT_L	0x40
#define	TEMP_OUT_H	0x41
#define	TEMP_OUT_L	0x42
#define	GYRO_XOUT_H	0x43
#define	GYRO_XOUT_L	0x44
#define	GYRO_YOUT_H	0x45
#define	GYRO_YOUT_L	0x46
#define	GYRO_ZOUT_H	0x47
#define	GYRO_ZOUT_L	0x48
#define	PWR_MGMT_1	0x6B
#define	WHO_AM_I	0x75	
#define	SlaveAddress	0xD0	
 
#define Address 0x68                  //MPU6050地址
 
#define I2C_RETRIES   0x0701
#define I2C_TIMEOUT   0x0702
#define I2C_SLAVE     0x0703       //IIC從器件的地址設定
#define I2C_BUS_MODE   0x0780
 
typedef unsigned char uint8;
 
int fd = -1;
 
//函式宣告
static uint8 MPU6050_Init(void);
static uint8 i2c_write(int fd, uint8 reg, uint8 val);
static uint8 i2c_read(int fd, uint8 reg, uint8 *val);
static uint8 printarray(uint8 Array[], uint8 Num);
 
 
//MPU6050初始化
static uint8 MPU6050_Init(void)
{
	fd = open("/dev/i2c-0", O_RDWR);   // open file and enable read and  write
 
	if(fd < 0)
	{
		perror("Can't open /dev/MPU6050 \n"); // open i2c dev file fail
		exit(1);
	}
	printf("open /dev/i2c-0 success !\n");   // open i2c dev file succes
 
	if(ioctl(fd, I2C_SLAVE, Address)<0) {    //set i2c address 
		printf("fail to set i2c device slave address!\n");
		close(fd);
		return -1;
	}
	printf("set slave address to 0x%x success!\n", Address);
 
	i2c_write(fd,PWR_MGMT_1,0X00);    
	i2c_write(fd,SMPLRT_DIV,0X07); 
	i2c_write(fd,CONFIG,0X06); 
	i2c_write(fd,ACCEL_CONFIG,0X01); 
 
	return(1);
}
 
 
 
//MPU6050 wirte byte
static uint8 i2c_write(int fd, uint8 reg, uint8 val)
{
	int retries;
	uint8 data[2];
 
	data[0] = reg;
	data[1] = val;
	for(retries=5; retries; retries--) {
		if(write(fd, data, 2)==2)
			return 0;
		usleep(1000*10);
	}
	return -1;
}
 
//MPU6050 read byte
static uint8 i2c_read(int fd, uint8 reg, uint8 *val)
{
	int retries;
 
	for(retries=5; retries; retries--)
		if(write(fd, &reg, 1)==1)
			if(read(fd, val, 1)==1)
				return 0;
	return -1;
}
 
//get data
short GetData(unsigned char REG_Address)
{
	char H,L;
	i2c_read(fd, REG_Address, &H);
	i2c_read(fd, REG_Address + 1, &L);
 
	return (H<<8)+L;
}
// main
int main(int argc, char *argv[])
{
	MPU6050_Init();
	usleep(1000*100);
	while(1)
	{
		printf("\033[2J");
		usleep(1000*200);
		printf("ACCE_X:%6d\n ",GetData(ACCEL_XOUT_H));
		printf("ACCE_Y:%6d\n ",GetData(ACCEL_YOUT_H));
		printf("ACCE_Z:%6d\n ",GetData(ACCEL_ZOUT_H));
		printf("GYRO_X:%6d\n ",GetData(GYRO_XOUT_H));
		printf("GYRO_Y:%6d\n ",GetData(GYRO_YOUT_H));
		printf("GYRO_Z:%6d\n ",GetData(GYRO_ZOUT_H));
	}
 
	close(fd);
}