IMU 9DOF problem

Hello to all!
I have bought this board:

But it seem don’t work properly, because i’m able only to read correctly the value of WHO_I_AM register (0x68),
for the all other registers (included registers PWR_MGMT_1 and WIA) i read ever the zero value… Why?

In this forum i have found this discussion:

Is possible that my board have the same problem? Anyone have the my same problem??

Thank you!

Be ware. The address of our IMU is 0x69.

Read carefully!
I read correctly only the value of WHO_I_AM register, which is always 0x68…
I know that the address of your IMU is 0x69, otherwise i not read nothing if i use the 0x68 address.

Can you try the I2C ping … s-scanner/?

I can try… I’m not a Arduino user, i must adapt the code without use the Arduino framework…

I see on I2C bus the 9DOF IMU because i send a read operation using your address (0x69) and the device return me the content of WHO_I_AM register that is always 0x68.
So i deducting that the device is present on I2C bus.

My problem is that i read only this register, for all the other registers, i read the zero value…

My code works well with the GY-521 board, in this case i read all the registers (incluse the WHO_I_AM and PWR_MGMT_1)

All I can tell you we test all IMU MPU9150 with the MultiWii code with the MPU6050 define.
We can test your board if you want.
Let me know.

I don’t know the multiwii code, i can try to study it and adapt it to my code.
However i think that i will send to you my board.

Have a Happy Christmas

I have rewrited and double checked my code and i think that it works well because i’m able to communicate with the AK8975 magnetometer present in the MPU9150 chip.
I read correctly the AK8975 ID register (register address = 0x00, register value = 0x48) and i read all the data registers of the AK8975 (from 0x03 to 0x08).
Also, using my code, i’m able to reading correctly the who_am_i register (register address 0x75 and register value 0x68) of the MPU6050 chip present in the MPU9150 chip, but i read correctly only this register.
For all the others registers i read always zero value included the register PWR_MGMT_1 (in the datasheet the default value of this register after power on should be 0x40, but i read the zero value!).
So i think that my code works well, but i think that the MPU6050 chip doesn’t works properly…
So I will send to you my board as soon as possible after the new years day.

Have a Happy New Years

Very strange! I have never seen the IMU with the AK8975 which work but not the MPU6050 in the chip.
Send us back the IMU and we will test it.
Happy new year.

I also think so! But believe me, i don’t know what is the problem!
From my point of view, the strange thing is the default value of the PWR_MGMT_1 register. This value should be 0x40, but I read the zero value.
I have another IMU (but only the MPU6050), and when i go to read the default value of the PWR_MGMT_1 register, i read the default value 0x40 in according with the datasheet.
If you have any suggestion, i can try to do anything, otherwise i will send the board to you as soon as possible.


Send the board please. It will be more easy!

I sent the card today. Let me know.

I have saw that the my imu it arrived at your address in the date 14/01/2014…
Any news?? It work?

The new board works very well!
Thank you so much!

You’re welcome! :wink: