Thingy:52 - MPU9250 Default Register Configuration

RE: Thingy:52 - MPU9250 Default Register Configuration

Nguyen Hoan Hoang — Fri, 18 Oct 2019 11:51:05 GMT

This driver is a lot easier to follow. https://github.com/IOsonata/IOsonata/blob/master/src/sensors/agm_mpu9250.cpp.

The example firmware that stream data to Thingy Apps. This firmware is made for a different board but made to be compatible with Thing App.

https://github.com/IOsonata/IOsonata/tree/master/ARM/Nordic/exemples/BlueIOThingy

RE: Thingy:52 - MPU9250 Default Register Configuration

Simonr — Fri, 18 Oct 2019 07:13:37 GMT

Hi Daniel

Sorry, but it took a few days before the R&D department got around to this. But here goes:

The MPU-9250 is a multi-chip module with the MPU-6500 (accelerometer and gyrometer) and the AKM-8963 (magnetometer) combined. If you take a look at the inv_mpu.c file (note that this file is made by Invensense and not Nordic Semiconductor), you can see the following:

#elif defined MPU9250           /* #if defined MPU9150 */
#ifndef MPU6500
#define MPU6500

This points to that when the MPU9250 is used, it uses the same configs as the MPU6500, which are located in that same file. If you need more information on how to decipher the inv_mpu files, you'll have to contact Invensense, as I can't confirm anything. The motion sensor is set up in the drv_motion.c file by us, using the inv_mpu.c files as reference.

Best regards,

Simon

RE: Thingy:52 - MPU9250 Default Register Configuration

Dan — Thu, 17 Oct 2019 15:26:08 GMT

Hi Simon,

It looks like it might have been in inv_mpu.c all along under the Thingy Libraries:

* @brief Initialize hardware.
* Initial configuration:\n
* Gyro FSR: +/- 2000DPS\n
* Accel FSR +/- 2G\n
* DLPF: 42Hz\n
* FIFO rate: 50Hz\n
* Clock source: Gyro PLL\n
* FIFO: Disabled.\n
* Data ready interrupt: Disabled, active low, unlatched.
* @param[in] int_param Platform-specific parameters to interrupt API.
* @return 0 if successful.
*/

It would be good to confirm, to make sure I am not missing anything that happens after a connection. Thanks so much.

*edit -- I would also still enjoy some feedback on the configuration string I mention above. How should that be deciphered?

Dan

RE: Thingy:52 - MPU9250 Default Register Configuration

Simonr — Tue, 15 Oct 2019 13:31:40 GMT

Hi Daniel

I had to ask the R&D department regarding this matter. Hopefully, I'll have an answer for you tomorrow. I'll make sure to update you as soon as I know something!

Best regards,

Simon