mpu9250_dmp_quaternion.ino not working - FREEMATICS ONE+ Model A

Discussion about software developed by Freematics, including Freematics Builder and Freematics Emulator GUI
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Joined: Sat May 22, 2021 12:14 am

mpu9250_dmp_quaternion.ino not working - FREEMATICS ONE+ Model A

Post by xWaspAx »

Hy guys,
I am new to this forum and I apologize if my form is not correct.

I've just received the Freematics ONE+ Model A OBD dongle and I am trying to test the onboard 9 axes IMU. I am using Arduino IDE (v 1.8.13) in order to program the ESP32 mcu of the device.
I've manually installed the library FreematicsPlus inside the following path:
The board selected is: "ESP32 Dev Module" (I've already instaledl the ESP32 Arduino package from the Board Manager as stated in the Quick Start Guide on the main website).
The device is connected and available through COM8 port on my Windows 10 pc.
So now I am trying to Upload the "mpu9250_dmp_quaternion.ino" sketch found between Arduino examples ( ... ernion.ino), to check if the IMU sensor is working well.
In conclusion, the error occurred when I try to compile is the following:

TestFREEMATICS:3:1: error: 'MPU9250_DMP' does not name a type
MPU9250_DMP imu;
C:\Users\matteo\Desktop\TestFREEMATICS\TestFREEMATICS.ino: In function 'void setup()':
TestFREEMATICS:10:8: error: 'imu' was not declared in this scope
if (!imu.begin(true, 10))
C:\Users\matteo\Desktop\TestFREEMATICS\TestFREEMATICS.ino: In function 'void loop()':
TestFREEMATICS:23:7: error: 'imu' was not declared in this scope
if (, 0, 0, 0, &ori)) {
exit status 1
'MPU9250_DMP' does not name a type

I'm not an IT guy with low Cpp programming skills, but I've checked the files in the library and all these files are good and seem fine:


Can someone please explain to me why the object imu is not found? And why I have this kind of error with the exact same code posted on Github?
Thanks a lot in advance
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