Setting up MPU 6050 DMP to fuse magnetometer data

Other Hardware Sensors
1

Arduino Playground - MPU-6050 as well as the datasheet mentions that the DMP is capable of retrieving and fusing data over auxiliary I2C. But I am not sure what adjustments need to be made. Is it enough to set Auxiliary I2C to master mode?
I have Flyduino 9DOF (MPU6050 + HMC5883L)

2

Connect the magnetometer to the same I2C bus as the MPU-6050. Forget about the auxiliary I2C. No worries, no trouble.

The 'dmp' of the MPU-6050 can contain some kind of firmware. That firmware could read data from a magnetometer. If you want to go there, then buy a MPU-9150. The MPU-9150 is a MPU-6050 with Magnetometer in the same chip. If you are buying a new sensor, why not the state-of-the-art sensor that does all the calculations for you : Adafruit 9-DOF Absolute Orientation IMU Fusion Breakout - BNO055 : ID 2472 : $34.95 : Adafruit Industries, Unique & fun DIY electronics and kits

It is also possible to set a register of the MPU-6050 to connect the normal I2C bus to the auxiliary I2C bus. To me that seems totally useless, since the normal I2C can be used as well.

3

As I said I a have flyduino breakout, that has this configuration and lets say not in position to choose the hardware. I would like to kindly ask to prvide the answer to the questions in first post

4

Do you have dmp code that uses the HMC5883L ? Did it come with example code for the Arduino ?
Or do you want the MPU-6050 to connect both I2C busses ?

I think the Master Mode should be enough for the dmp code.

The reference page for the flyduino 9DOF seems to be removed ? I can't find specifications or a schematic.
I found it in the Archive.org : Flyduino 9DOF IMU MPU6050+HMC5883l
But I still can't find a schematic.

5

Hi,

According to MPU-6050 6-axis accelerometer/gyroscope | I2C Device Library, " the DMP cannot produce fully fused 9-axis orientation data without some external computation done on the host processor. The DMP does not have the processing power necessry to do compute 9-axis fused data, even if the magnetometer is connected and properly configured as a slave device on the MPU-6050’s AUX SDA/SCL lines." Hope you've already considered that!