#include <18F46J50.h>
#fuses HSPLL, NOWDT, PLL4, NOXINST, NOCPUDIV, NOFCMEN, NOIESO, NOIOL1WAY, STVREN
#use delay(clock=48000000)
#use I2C(MASTER, SDA=PIN_D1, SCL=PIN_D0)

#include ".\include\usb_cdc.h"
#include "mylib.h"
#include "adxl345.h" //Accel
#include "itg3200.h" //Gyro
#include <math.h>

#define GREEN_LED PIN_A1
#define RED_LED   PIN_A2
#define ON   output_high
#define OFF  output_low

float RwAcc[3]; //Projection of normalized gravitation force vector on x/y/z axis, as measured by accelerometer
float rates[3]; //Gyro angular rates

void main(void) {

   setup_oscillator(OSC_PLL_ON);
   delay_ms(1000);
   TRISD=0×03; //RD0 (SCL2) and RD1 (SDA2) inputs 

   ON(GREEN_LED);    
   usb_cdc_init();
   usb_init();
   ON(RED_LED);   
   usb_wait_for_enumeration();
   delay_ms(100);
   OFF(RED_LED);
   OFF(GREEN_LED);
   delay_ms(100);

   //Accel init
   adxl345_init();

   //Gyro init
   itg3200_init_setup(); 
   itg3200_init();
   
   while (1){

      usb_task(); //you must call 'task', before testing 'enumerated'.
      if(usb_enumerated()) ON(GREEN_LED); 
      else OFF(GREEN_LED);

      //ACCEL readings
      RwAcc[0]=adxl345_get_accel_data(adxl345_get_data_x());
      RwAcc[1]=adxl345_get_accel_data(adxl345_get_data_y());
      RwAcc[2]=adxl345_get_accel_data(adxl345_get_data_z());
    
      //Gyro readings
      rates[0]=itg3200_get_angular_rate(itg3200_get_rate_x()); 
      rates[1]=itg3200_get_angular_rate(itg3200_get_rate_y()); 
      rates[2]=itg3200_get_angular_rate(itg3200_get_rate_z());

      //Print sensor readings
      printf(usb_cdc_putc,"Xa=%1.2f Ya=%1.2f Za=%1.2f Xg=%1.2f Yg=%1.2f Zg=%1.2f\r\n",RwAcc[0],RwAcc[1],RwAcc[2],rates[0],rates[1],rates[2]);

      delay_ms(100);
   } 
}

adxl345.h is:

#define ACCEL_ADDR_WRITE     0xA6
#define ACCEL_ADDR_READ      0xA7
#define accel_measure_mode  0×08

//READ/WRITE REGISTERS 
#define THRESH_TAP         0x1D //Threshold tap
#define OFSX            0x1E //X-axis offset
#define OFSY            0x1F //Y-axis offset
#define OFSZ            0×20 //Z-axis offset
#define DUR                0×21 //Tap duration
#define LATENT            0×22 //Tap latency
#define WINDOW            0×23 //Tap window
#define THRESH_ACT        0×24 //Activity threshold
#define THRESH_INACT    0×25 //Inactivity threshold
#define TIME_INACT        0×26 //Inactivity time
#define ACT_INACT_CTL    0×27 //Axis enable control for activity and inactivity detection
#define THRESH_FF        0×28 //Free-fall threshold
#define TIME_FF            0×29 //Free-fall time
#define TAP_AXES        0x2A //Axis control for single tap/double tap
#define BW_RATE            0x2C //Data rate and power mode control
#define POWER_CTL        0x2D //Power-saving features control
#define INT_ENABLE        0x2E //Interrupt enable control
#define INT_MAP            0x2F //Interrupt mapping control
#define DATA_FORMAT        0×31 //Data format control. Por defecto: +-2g: sensibilidad 256
#define FIFO_CTL        0×38 //FIFO control
//READ-ONLY REGISTERS 
#define DEVID             0×00 //Device ID
#define ACT_TAP_STATUS     0x2B //Source of single tap/double tap
#define INT_SOURCE         0×30 //Source of interrupts 
#define ACCEL_DATAX0    0×32 //X-Axis Data 0
#define ACCEL_DATAX1    0×33 //X-Axis Data 1
#define ACCEL_DATAY0    0×34 //Y-Axis Data 0
#define ACCEL_DATAY1    0×35 //Y-Axis Data 1
#define ACCEL_DATAZ0    0×36 //Z-Axis Data 0
#define ACCEL_DATAZ1    0×37 //Z-Axis Data 1
#define FIFO_STATUS        0×39 //FIFO status
 
//Sensitivity at XOUT, YOUT, ZOUT. ±2 g, 10-bit resolution
#define ACCEL_SENSITIVITY 256.0f // LSB per g 

/////FUNCTIONS
 
//single register write 
void adxl345_write_reg(int8 ADDR, int8 VAL) 
{ 
    i2c_start(); 
       i2c_write(ACCEL_ADDR_WRITE); 
       i2c_write(ADDR); 
       i2c_write(VAL); 
       i2c_stop(); 
}

//single register read 
int8 adxl345_read_reg(int8 ADDR) 
{ 
    int8 val; 
       i2c_start(); 
      i2c_write(ACCEL_ADDR_WRITE); 
       i2c_write(ADDR); 
       i2c_start(); 
       i2c_write(ACCEL_ADDR_READ); 
       val=i2c_read(0); //NACK to end transmission 
       i2c_stop(); 
       return val; 
} 

void adxl345_init()
{
    i2c_start(); 
       i2c_write(ACCEL_ADDR_WRITE);     
       i2c_write(POWER_CTL);             
       i2c_write(ACCEL_MEASURE_MODE);  
       i2c_stop(); 
}

signed int16 adxl345_get_data_x() 
{ 
    //DATAX0 is LSByte and DATAX1 is MSByte
       signed int16 xdata; 
       xdata=(adxl345_read_reg(ACCEL_DATAX1)<<8); 
       xdata|=adxl345_read_reg(ACCEL_DATAX0); 
       return xdata; 
} 

signed int16 adxl345_get_data_y() 
{ 
       signed int16 ydata; 
       ydata=(adxl345_read_reg(ACCEL_DATAY1)<<8); 
       ydata|=adxl345_read_reg(ACCEL_DATAY0); 
       return ydata; 
} 

signed int16 adxl345_get_data_z() 
{ 
       signed int16 zdata; 
       zdata=(adxl345_read_reg(ACCEL_DATAZ1)<<8); 
       zdata|=adxl345_read_reg(ACCEL_DATAZ0); 
       return zdata; 
} 

float adxl345_get_accel_data(signed int16 VAL) 
{ 
   float tmpf; 
   tmpf = VAL/ACCEL_SENSITIVITY; //convert raw value to g 
   return tmpf; 
}

And itg3200.h is the driver version writen by simonspt in this thread:

http://www.ccsinfo.com/forum/viewtopic.php?t=47649&highlight=adxl345+itg3200

Thank you very much.

http://imageshack.us/a/img694/9966/accelgyro.jpg

Thanks. 

I'm making progress with my IMU thanks to your guide. I'm able to read accel and gyro measures, but I don't know the reason why I get so many glitches in RyAcc. In this image you can see it:

In the image the devide is placed in horizontal position, so both X and Y outputs from accelereometer are zero. Any idea?

Thank you very much.

http://code.google.com/p/serialchart/issues/detail?id=1&can=1

Serial chart is not working ing my PC, is this compatible with Windows Starter?

I tried to use the ZIPPED version, but when i hit the run button it gives me an error message

"Could not open port COM26"

but I am 100% sure that my Arduino is Connected at com26 and I already configure the serial chart.

I also tried to close all the applications running on my PC except Serial chart. But still got the same error. 

Can someone Help me.. 

Congratulations guide on IMU and application SerialChart, his explanations are simple and really work!

I'm doing the same job, but with other models of sensors and my question is regarding the complementary filter:

1) In the complementary filter (in the arduino code) is performed a weighted

"RwEst [w] = (RwAcc [w] + config.wGyro RwGyro * [w]) / (1 + config.wGyro);"

that worked perfectly, but I have seen other articles that I talk about complementary filters and saw there another equation of the type:

"angle = (0.98) * (angle + Rwgyro * dt) + (0.02) * (Rwacc);" or
"angle = a * (angle + Rwgyro * dt) + (1-a) * RwAcc"

where a = tau / (t + tau)

you can see that the two forms is given a value greater than one sensor to another. Only I could not see where the variable "a" in your solution, and referred to this time constant than the other articles speak.

Thanks for your time!

And this is my current serial chart configuration file:
http://www.timdemeyer.be/files/MPU-6050-kalman.scc

Serial.print(a); Serial.print(",");
Serial.print(b); Serial.print(",");
Serial.println(c);

I also tried with other data, but same results… Am I doing something wrong?
Thanks in advance!

I have a question, please help me!

I want to extract the Euler angels relative to earth frame from gyro's outputs in a simulation study by using eqs: 17-21. Hence, in my code it is assumed that the gyro rotate about its x axis with angular velocity of 1 deg/sec and dt=20msec.

I except that after 1 second; pitch, roll and yaw values to be 0, 1 and 1 degree respectively. But I never receive to this result. I am very confused. Are my exception is correct? Furthermore, these angles have large variation. What is my mistake point?

Best regards