I connected to my MPU-9105 and it seems to be responding correctly, but all I get are zeros from the accel/gyro sensor registers and sleep mode is off

[deamonata]

Hi there,

 

I've been having a lot of issues with the 9150, I attempting to interface between a C8051F411 and the MPU-9150. I have successfully inmplemented the I2C buss communication and can talk to the device, I can comfortably read and write to most registers however if I read and write to the accel/gyro sensor registers all I get back is zeros.

 

Obviously my first thought was the sleep mode, however I check and I am deffinatly setting the PWR_MGMT_1 register to 0x02 in my code, and more importantly if I read the register back to check the value I can confirm it has been set correctly.

 

I set the following registers

    SMB_Write_To_Register (REG_PWR_MGMT_1, PWR_MGMT_1_RESET);	// resets the chip
    for (i=0;i<20000;i++);
    SMB_Write_To_Register (PWR_MGMT_1, 0x02);
    for (i=0;i<20000;i++);   
    SMB_Write_To_Register (SMPRT_DIV, 0x07);
    SMB_Write_To_Register (CONFIG, 0x00);
    SMB_Write_To_Register (GYRO_CONFIG, 0x00);
    SMB_Write_To_Register (ACCEL_CONFIG, 0x00);
    SMB_Write_To_Register (FF_THR, 0x00);
    SMB_Write_To_Register (FF_DUR, 0x00);
    SMB_Write_To_Register (MOT_THR, 0x00);
    SMB_Write_To_Register (MOT_DUR, 0x00);
    SMB_Write_To_Register (ZRMOT_THR, 0x00);
    SMB_Write_To_Register (ZRMOT_DUR, 0x00);
    SMB_Write_To_Register (FIFO_EN, 0x00);
    SMB_Write_To_Register (I2C_MST_CTRL, 0x00);
    SMB_Write_To_Register (I2C_SLV0_ADDR, 0x00);
    SMB_Write_To_Register (I2C_SLV0_REG, 0x00);
    SMB_Write_To_Register (I2C_SLV0_CTRL, 0x00);
    SMB_Write_To_Register (I2C_SLV1_ADDR, 0x00);
    SMB_Write_To_Register (I2C_SLV1_REG, 0x00);
    SMB_Write_To_Register (I2C_SLV1_CTRL, 0x00);
    SMB_Write_To_Register (I2C_SLV2_ADDR, 0x00);
    SMB_Write_To_Register (I2C_SLV2_REG, 0x00);
    SMB_Write_To_Register (I2C_SLV2_CTRL, 0x00);
    SMB_Write_To_Register (I2C_SLV3_ADDR, 0x00);
    SMB_Write_To_Register (I2C_SLV3_REG, 0x00);
    SMB_Write_To_Register (I2C_SLV3_CTRL, 0x00);
    SMB_Write_To_Register (I2C_SLV4_ADDR, 0x00);
    SMB_Write_To_Register (I2C_SLV4_REG, 0x00);
    SMB_Write_To_Register (I2C_SLV4_DO, 0x00);
    SMB_Write_To_Register (I2C_SLV4_CTRL, 0x00);
    SMB_Write_To_Register (INT_PIN_CFG, 0x00);
    SMB_Write_To_Register (INT_ENABLE, 0x00);
    SMB_Write_To_Register (I2C_SLV0_DO, 0x00);
    SMB_Write_To_Register (I2C_SLV1_DO, 0x00);
    SMB_Write_To_Register (I2C_SLV2_DO, 0x00);
    SMB_Write_To_Register (I2C_SLV3_DO, 0x00);
    SMB_Write_To_Register (I2C_MST_DELAY_CTRL, 0x00);
    SMB_Write_To_Register (SIGNAL_PATH_RESET, 0x00);
    SMB_Write_To_Register (MOT_DETECT_CTRL, 0x00);
    SMB_Write_To_Register (USER_CTRL, 0x00);
    SMB_Write_To_Register (PWR_MGMT_2, 0x00);
    SMB_Write_To_Register (FIFO_R_W, 0x00);

The logic analyzer I have confirms that everything is getting sent correctly and I am getting acknowleges back from the MPU-9150. I've kinda run out of ideas now as to why it isn't working

 

 

[Jeff Rowberg]

Is there a particular reason you are writing to every register as part of the initialization? After a reset, they should all be in the 0x00 state automatically with the exception of PWR_MGMT_1, which defaults to sleep mode. For a simple test, can you power it on and write 0x00 to register 0x6B, and then read ACCEL_XOUT_H/L (sequentially) repeatedly to see what comes out?

 

You do have the AD0 pin tied to either GND or VDD, and (if applicable) the VIO pin also tied to VDD?

[deamonata]

I was writing to every register because my code wasn't working when I was only writing a few settings to it, but I thought that maybe one wan't initialising properly. However it turns out the problem was with the chip and having replaced the chip I can now read from the accelerometer and gyroscope, but the magnometer is still causing me issues.

I've determined that I should be at the address 0x0C, and I sent 0x01 to the register 0x0A before reading anything. however all I am getting back are zeros.

what are the steps that I should be doing to read from the magnometer? I assume I must be missing something.

[Jeff Rowberg]

I haven't done much with the AK8975 operating inside the MPU-9150, but there is this sketch meant to use the AK8975 through the MPU-6010:

 

https://github.com/jrowberg/i2cdevlib/tree/master/Arduino/AK8975/Examples/AK8975_MPUEVB_heading

 

The register map for the device is here:

 

http://www.i2cdevlib.com/devices/ak8975#registers

 

The same code applies to the 9150, but I think it needs to be modified for the different slave address.

[dpereztaylor]

Hi  deamonata, I´m having the same problem, did you find out, how to solve it? 

 

thanks

[shyamthella]

Hi Jeff,

 

I have been using Mpu9150 and I am able to get the data from registers.

But the problem is I am getting some junk (corrupted) data from one or all of the six data registers of accelerometer.

The log looks like this:

 

 

  MPU9150 Accelerometer Sensor Loaded

 

 

####### mpu9150 probe called ############# 

  ####### mpu9150_probe:558 Read ID:=68

####### mpu9150_probe:578 

input: mpu9150 as /devices/virtual/input/input2

####### mpu9150_probe:603 

####### Mpu9150 probe finished

 

0:0xfffffff4 1:0xffffffbc 2:0x2 3:0xfffffff4 4:0xffffffbd 5:0x2c 

ax:-68 ay:-12 az:-17108

 

0:0xfffffff4 1:0x40 2:0x2 3:0xffffffec 4:0xffffffbd 5:0x1c 

ax:-3008 ay:-20 az:-17124

 

0:0xfffffff4 1:0x48 2:0x2 3:0xffffffc0 4:0xffffffbc 5:0xffffffc8 

ax:-3000 ay:-64 az:-56

 

0:0xfffffff4 1:0x70 2:0x3 3:0x44 4:0xffffffbc 5:0xffffffa0 

ax:-2960 ay:836 az:-96

 

0:0xfffffff4 1:0x64 2:0x3 3:0x1c 4:0xffffffbc 5:0xffffffc0 

ax:-2972 ay:796 az:-64

 

0:0xfffffff4 1:0xffffffa0 2:0x3 3:0x20 4:0xffffffbd 5:0xffffff84 

ax:-96 ay:800 az:-124

 

0:0xfffffff4 1:0x40 2:0x2 3:0xffffffcc 4:0xffffffbc 5:0xffffffac 

ax:-3008 ay:-52 az:-84

 

0:0xfffffff4 1:0x74 2:0x2 3:0xffffffd4 4:0xffffffbc 5:0xffffffc4 

ax:-2956 ay:-44 az:-60

 

0:0xfffffff4 1:0x1c 2:0x2 3:0xffffffb8 4:0xffffffbc 5:0xffffffa8 

ax:-3044 ay:-72 az:-88

 

0:0xfffffff4 1:0x78 2:0x2 3:0xfffffff0 4:0xffffffbd 5:0x10 

ax:-2952 ay:-16 az:-17136

 

0:0xfffffff4 1:0x38 2:0x2 3:0xffffff90 4:0xffffffbc 5:0xffffffac 

ax:-3016 ay:-112 az:-84

 

0:0xfffffff4 1:0x50 2:0x2 3:0xffffffe8 4:0xffffffbd 5:0x34 

ax:-2992 ay:-24 az:-17100

 

0:0xfffffff4 1:0xffffff9c 2:0x2 3:0xffffff98 4:0xffffffbc 5:0xffffffc8 

ax:-100 ay:-104 az:-56

 

0:0xfffffff4 1:0xffffffdc 2:0x2 3:0xffffffdc 4:0xffffffbc 5:0xfffffffc 

ax:-36 ay:-36 az:-4

 

0:0xfffffff4 1:0x60 2:0x3 3:0x24 4:0xffffffbc 5:0x7c 

ax:-2976 ay:804 az:-17284

 

0:0xfffffff4 1:0x18 2:0x2 3:0xffffff9c 4:0xffffffbd 5:0x0 

ax:-3048 ay:-100 az:-17152

 

0:0xfffffff4 1:0x74 2:0x2 3:0xfffffff0 4:0xffffffbc 5:0xffffffe4 

ax:-2956 ay:-16 az:-28

 

0:0xfffffff4 1:0x58 2:0x2 3:0xffffffcc 4:0xffffffbc 5:0xffffffcc 

ax:-2984 ay:-52 az:-52

 

0:0xfffffff4 1:0xffffffac 2:0x2 3:0xffffffe0 4:0xffffffbc 5:0xffffffa4 

ax:-84 ay:-32 az:-92

 

0:0xfffffff4 1:0x38 2:0x2 3:0xffffff84 4:0xffffffbd 5:0xffffffb4 

ax:-3016 ay:-124 az:-76

 

0:0xfffffff4 1:0x58 2:0x2 3:0xffffffc0 4:0xffffffbc 5:0xffffffb0 

ax:-2984 ay:-64 az:-80

 

0:0xfffffff4 1:0xffffffa4 2:0x2 3:0xffffffcc 4:0xffffffbc 5:0xffffff88 

ax:-92 ay:-52 az:-120

 

0:0xfffffff4 1:0xffffff94 2:0x2 3:0xffffffc0 4:0xffffffbc 5:0xfffffff0 

ax:-108 ay:-64 az:-16

 

0:0xfffffff4 1:0x6c 2:0x2 3:0xffffffe0 4:0xffffffbd 5:0x18 

ax:-2964 ay:-32 az:-17128

 

0:0xfffffff4 1:0xffffffb8 2:0x3 3:0x0 4:0xffffffbc 5:0xffffffd8 

ax:-72 ay:768 az:-40

 

0:0xfffffff4 1:0xffffff90 2:0x3 3:0x2c 4:0xffffffbd 5:0xffffffd0 

ax:-112 ay:812 az:-48

 

0:0xfffffff4 1:0x78 2:0x2 3:0xfffffff8 4:0xffffffb9 5:0xffffffd8 

ax:-2952 ay:-8 az:-40

 

0:0xfffffff4 1:0x40 2:0x3 3:0x48 4:0xffffffba 5:0xffffffd4 

ax:-3008 ay:840 az:-44

 

0:0xfffffff4 1:0x48 2:0x3 3:0x24 4:0xffffffbb 5:0xffffffc4 

ax:-3000 ay:804 az:-60

 

0:0xfffffff4 1:0xffffff8c 2:0x2 3:0xffffffc8 4:0xffffffbd 5:0xffffffac 

ax:-116 ay:-56 az:-84

 

0:0xfffffff4 1:0xffffff90 2:0x2 3:0xffffff8c 4:0xffffffbd 5:0x68 

ax:-112 ay:-116 az:-17048

 

 

Please suggest me in solving this issue.

 

Regards,

Shyam Kumar

[jctang46]

Jeff, I recently got a 10 DOF board with InvenSense new MPU9255. Do you think code and libraries used for MPU9150 could be ported to this new chip without re-coding (for only data acquisition, like read quaternion out from FIFO)?

 

 

If anybody has experience of using MPU9255?