Do gyroscopes purposefully show erroneous data? I tested an MPU-6050 (GY-521) using an Arduino Nano. I used the I2CDevLib and opened the MPU6050_DMP6.ino with the Arduino IDE. I opened the MPUTeapot.pde Processing-file with Processing. A few changes was necessary to make it work:

MPU6050 mpu;


was changed into:

MPU6050 mpu(0x68);


Additionally I commented out this line:

#define OUTPUT_READABLE_YAWPITCHROLL


and uncommented this line:

#define OUTPUT_TEAPOT


When turning everything on, the arrow (Processing) would turn with 5 degrees/s clockwise around the z-axis (plus a very small amount around the other two axes). After about 20 seconds, it would stop, and turn around the x-axis pretty fast for 3 seconds. Then it would stop. Now, the gyroscope+accelerometer would work perfectly. This happens every time I test it.

This happens only when the gyroscope is perfectly still on the ground. It does not stabilize if I move it around. Only after it is left completely still, it'll stabilize after 23 seconds.

Is this how it should work, or is it a problem with the gyroscope? Could it even be caused by the I2CDevLib? Can anybody else confirm this?
MPU6050 is a chip that has an intenal (closed and unknown) algorith to calculate orientation. Because you ar reading ANGLE, that means you are using that algoritm, and that "time" may be the time needed for the calibration.

what do you have as output on the serial?