QuaternionFilter Unstable q values

[beaumr2]

Hi Kris

First of all, thank you for this.

So I'm using your code and having trouble with the QuaternionFilter. The accelerometer, gyroscope, and magnetometer values are stable but my q values vary wildly (and seem to want to alternate between positive and negative) which is messing up my pitch, roll, and yaw.

Do you have any idea what might be causing this? I'm using Arduino Uno and your code. I can paste the code if needed but here's the output:

x-axis self test: acceleration trim within : 0.7% of factory value y-axis self test: acceleration trim within : -0.5% of factory value z-axis self test: acceleration trim within : 2.3% of factory value x-axis self test: gyration trim within : 34.6% of factory value y-axis self test: gyration trim within : 14.5% of factory value z-axis self test: gyration trim within : 0.8% of factory value accel biases (mg) -318.97 370.91 -494.32 gyro biases (dps) -4.59 -9.87 -0.75 MPU9250 initialized for active data mode.... AK8963 I AM 48 I should be 48 AK8963 initialized for active data mode.... AK8963 mag biases (mG) 71.04 122.43 -36.90 AK8963 mag scale (mG) 1.01 1.03 0.96 Calibration values: X-Axis sensitivity adjustment value 1.16 Y-Axis sensitivity adjustment value 1.17 Z-Axis sensitivity adjustment value 1.13

ax = 0.73 ay = 0.37 az = 995.42 mg gx = -0.03 gy = -0.23 gz = -0.17 deg/s mx = 0 my = 0 mz = 0 mG q0 = 1.00 qx = 0.00 qy = 0.00 qz = 0.00 Gyro temperature is 34.0 degrees C Yaw, Pitch, Roll: 13.80, 0.00, 0.00 Grav_x, Grav_y, Grav_z: 0.00, 0.00, 1000.00 mg Lin_ax, Lin_ay, Lin_az: 0.73, 0.37, -4.58 mg rate = 1.04 Hz

ax = 0.55 ay = -1.34 az = 995.30 mg gx = 0.05 gy = 0.05 gz = -0.12 deg/s mx = 27111 my = 164 mz = 35 mG q0 = 0.64 qx = -0.00 qy = 0.00 qz = -0.77 Gyro temperature is 34.1 degrees C Yaw, Pitch, Roll: 273.04, 0.00, -0.13 Grav_x, Grav_y, Grav_z: 2.33, 0.08, 1000.00 mg Lin_ax, Lin_ay, Lin_az: -1.78, -1.43, -4.70 mg rate = 4.87 Hz

ax = 376.28 ay = -1855.29 az = 494.32 mg gx = 0.05 gy = 0.05 gz = -0.12 deg/s mx = 27111 my = 164 mz = 35 mG q0 = 0.51 qx = -0.33 qy = 0.60 qz = -0.52 Gyro temperature is 21.1 degrees C Yaw, Pitch, Roll: 268.09, 16.15, -86.28 Grav_x, Grav_y, Grav_z: 958.51, 278.15, 62.35 mg Lin_ax, Lin_ay, Lin_az: -582.23, -2133.44, 431.97 mg rate = 4.87 Hz

ax = 376.28 ay = -1855.29 az = 494.32 mg gx = 0.05 gy = 0.05 gz = -0.12 deg/s mx = 27111 my = 164 mz = 35 mG q0 = 0.41 qx = -0.17 qy = -0.18 qz = -0.88 Gyro temperature is 21.1 degrees C Yaw, Pitch, Roll: 241.13, -26.40, 10.91 Grav_x, Grav_y, Grav_z: -169.48, -444.57, 879.57 mg Lin_ax, Lin_ay, Lin_az: 545.76, -1410.72, -385.24 mg rate = 4.87 Hz

[kriswiner]

I am asking what are the at-rest accel and gyro values after calibration. They should be 0, 0, 1000 millig and 0, 0, 0 dps. Are they?

On Thu, Aug 13, 2020 at 1:29 PM beaumr2 notifications@github.com wrote:

Ignore that last part I said, I realized it puts out calibration values for accelerometer and gyroscope before doing the figure 8 magnetic calibration

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[beaumr2]

Oh, yeah, they mostly are except the Accel z value is negative:

ax = 0.98 ay = 1.89 az = -1004.76 mg gx = -0.04 gy = 0.20 gz = 0.01 deg/s mx = 6 my = 13 mz = 6 mG q0 = 0.03 qx = -0.44 qy = 0.90 qz = -0.04 Pitch & Roll: 0.96, -174.92 Maximum Pitch & Roll 32.73,179.73 ax = 2.99 ay = -0.92 az = -999.82 mg gx = -0.07 gy = 0.33 gz = 0.15 deg/s mx = 4 my = -7 mz = -1 mG q0 = -0.02 qx = -0.45 qy = 0.89 qz = -0.03 Pitch & Roll: -3.48, -178.32 Maximum Pitch & Roll 32.73,179.73 ax = 0.73 ay = -0.06 az = -1000.06 mg gx = -0.01 gy = 0.34 gz = 0.08 deg/s mx = 9 my = -1 mz = 0 mG q0 = -0.01 qx = -0.50 qy = 0.87 qz = -0.01 Pitch & Roll: -1.45, -179.37 Maximum Pitch & Roll 32.73,179.73 ax = 3.17 ay = -0.55 az = -1001.16 mg gx = -0.24 gy = 0.43 gz = 0.21 deg/s mx = 11 my = -11 mz = 1 mG q0 = 0.03 qx = -0.53 qy = 0.85 qz = 0.04

[kriswiner]

Little more jitter than I would expect but good enough. Now try to calibrate the mag. if you just need pitch and roll, then you should be using a 6 DoF fusion algorithm that ignores the mag.

On Thu, Aug 13, 2020 at 1:39 PM beaumr2 notifications@github.com wrote:

Oh, yeah, they mostly are except the Accel z value is negative:

ax = 0.98 ay = 1.89 az = -1004.76 mg gx = -0.04 gy = 0.20 gz = 0.01 deg/s mx = 6 my = 13 mz = 6 mG q0 = 0.03 qx = -0.44 qy = 0.90 qz = -0.04 Pitch & Roll: 0.96, -174.92 Maximum Pitch & Roll 32.73,179.73 ax = 2.99 ay = -0.92 az = -999.82 mg gx = -0.07 gy = 0.33 gz = 0.15 deg/s mx = 4 my = -7 mz = -1 mG q0 = -0.02 qx = -0.45 qy = 0.89 qz = -0.03 Pitch & Roll: -3.48, -178.32 Maximum Pitch & Roll 32.73,179.73 ax = 0.73 ay = -0.06 az = -1000.06 mg gx = -0.01 gy = 0.34 gz = 0.08 deg/s mx = 9 my = -1 mz = 0 mG q0 = -0.01 qx = -0.50 qy = 0.87 qz = -0.01 Pitch & Roll: -1.45, -179.37 Maximum Pitch & Roll 32.73,179.73 ax = 3.17 ay = -0.55 az = -1001.16 mg gx = -0.24 gy = 0.43 gz = 0.21 deg/s mx = 11 my = -11 mz = 1 mG q0 = 0.03 qx = -0.53 qy = 0.85 qz = 0.04

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[beaumr2]

When it's still after doing the figure 8 calibration the values are actually worse:

ax = -768.07 ay = 123.60 az = -695.25 mg gx = 21.07 gy = 6.95 gz = 5.22 deg/s mx = -223 my = 789 mz = -749 mG q0 = -0.08 qx = -0.27 qy = 0.88 qz = 0.39 Pitch & Roll: 3.82, 133.26 Maximum Pitch & Roll 45.92,135.16 ax = -765.32 ay = 125.18 az = -695.07 mg gx = 21.22 gy = 6.90 gz = 5.19 deg/s mx = -207 my = 787 mz = -748 mG q0 = -0.11 qx = -0.34 qy = 0.85 qz = 0.38 Pitch & Roll: 4.11, 133.08 Maximum Pitch & Roll 45.92,135.16 ax = -757.69 ay = 126.89 az = -698.12 mg gx = 20.90 gy = 7.16 gz = 5.50 deg/s mx = -214 my = 794 mz = -746 mG q0 = -0.14 qx = -0.41 qy = 0.82 qz = 0.38 Pitch & Roll: 4.54, 132.92 Maximum Pitch & Roll 45.92,135.16 ax = -764.83 ay = 122.80 az = -698.97 mg gx = 21.13 gy = 6.47 gz = 5.00 deg/s mx = -248 my = 795 mz = -749 mG q0 = -0.16 qx = -0.47 qy = 0.79 qz = 0.37 Pitch & Roll: 4.89, 132.89 Maximum Pitch & Roll 45.92,135.16 ax = -758.54 ay = 125.43 az = -700.99 mg gx = 21.16 gy = 7.45 gz = 5.43 deg/s mx = -214 my = 787 mz = -755 mG q0 = -0.19 qx = -0.53 qy = 0.75 qz = 0.35 Pitch & Roll: 5.19, 133.03 Maximum Pitch & Roll 45.92,135.16 ax = -757.32 ay = 126.65 az = -703.12 mg gx = 21.18 gy = 6.62 gz = 5.09 deg/s mx = -236 my = 785 mz = -763 mG q0 = -0.21 qx = -0.59 qy = 0.70 qz = 0.34 Pitch & Roll: 5.68, 132.98 Maximum Pitch & Roll 45.92,135.16 ax = -757.57 ay = 126.71 az = -701.35 mg gx = 21.19 gy = 6.75 gz = 5.14 deg/s mx = -229 my = 795 mz = -752 mG

[kriswiner]

This makes no sense.

First you should let the sensor lie still to calibrate the accel and gyro, then after this is done, the mag calibration requires you move the board in all directions. If these are done in sequence, the gyro values should still read near zero when the device is again at rest...

On Thu, Aug 13, 2020 at 1:42 PM beaumr2 notifications@github.com wrote:

When it's still after doing the figure 8 calibration the values are actually worse:

ax = -768.07 ay = 123.60 az = -695.25 mg gx = 21.07 gy = 6.95 gz = 5.22 deg/s mx = -223 my = 789 mz = -749 mG q0 = -0.08 qx = -0.27 qy = 0.88 qz = 0.39 Pitch & Roll: 3.82, 133.26 Maximum Pitch & Roll 45.92,135.16 ax = -765.32 ay = 125.18 az = -695.07 mg gx = 21.22 gy = 6.90 gz = 5.19 deg/s mx = -207 my = 787 mz = -748 mG q0 = -0.11 qx = -0.34 qy = 0.85 qz = 0.38 Pitch & Roll: 4.11, 133.08 Maximum Pitch & Roll 45.92,135.16 ax = -757.69 ay = 126.89 az = -698.12 mg gx = 20.90 gy = 7.16 gz = 5.50 deg/s mx = -214 my = 794 mz = -746 mG q0 = -0.14 qx = -0.41 qy = 0.82 qz = 0.38 Pitch & Roll: 4.54, 132.92 Maximum Pitch & Roll 45.92,135.16 ax = -764.83 ay = 122.80 az = -698.97 mg gx = 21.13 gy = 6.47 gz = 5.00 deg/s mx = -248 my = 795 mz = -749 mG q0 = -0.16 qx = -0.47 qy = 0.79 qz = 0.37 Pitch & Roll: 4.89, 132.89 Maximum Pitch & Roll 45.92,135.16 ax = -758.54 ay = 125.43 az = -700.99 mg gx = 21.16 gy = 7.45 gz = 5.43 deg/s mx = -214 my = 787 mz = -755 mG q0 = -0.19 qx = -0.53 qy = 0.75 qz = 0.35 Pitch & Roll: 5.19, 133.03 Maximum Pitch & Roll 45.92,135.16 ax = -757.32 ay = 126.65 az = -703.12 mg gx = 21.18 gy = 6.62 gz = 5.09 deg/s mx = -236 my = 785 mz = -763 mG q0 = -0.21 qx = -0.59 qy = 0.70 qz = 0.34 Pitch & Roll: 5.68, 132.98 Maximum Pitch & Roll 45.92,135.16 ax = -757.57 ay = 126.71 az = -701.35 mg gx = 21.19 gy = 6.75 gz = 5.14 deg/s mx = -229 my = 795 mz = -752 mG

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[beaumr2]

That's what I'm doing. I let the sensor lie still on the table until it asks me to wave in a figure 8 for magnetic calibration. Then I wave it around until complete and then let it lie still again.

Maybe it's because it's not flat on the table? The soldering + wire prevents it from laying flat

[beaumr2]

Okay so I think I may have realized the problem. The accel values change based on how it lays on the table (it's not exactly flat every time). So when it's calibrated initially it's calibrated for one specific orientation on the table and then if I put it down again it lays differently and gives different accel values. It's probably feeling the effects of gravity in different axes

[beaumr2]

And you're saying the magnetic calibration is totally irrelevant to pitch and roll? Only affects yaw? So I can take that out completely?

[kriswiner]

Yeah, but the problem you have is that after mag calibration, the gyro says 21 dps, which is just nuts for a motionless sensor. So something is uber-wrong here...

On Thu, Aug 13, 2020 at 2:08 PM beaumr2 notifications@github.com wrote:

And you're saying the magnetic calibration is totally irrelevant to pitch and roll? Only affects yaw? So I can take that out completely?

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[beaumr2]

I did the procedure a few more times and am consistently getting gx, gy, and gz values close to zero when at rest. So that's good. Not sure what happened the other time

[beaumr2]

It may have been the other time I moved it during accel and gyro calibration

[beaumr2]

So here is hopefully my final question (sorry for bothering you so much). Situation: Pitch and roll is stable, MPU9250 is at rest Move MPU9250 Place MPU9250 at rest Pitch and roll jump around for a few seconds before becoming stable.

I assume it's something about the sampling rate?

[kriswiner]

Something to do with the fusion rate...the filter is iterative. It needs to be run between 10 and 20 times for each new gyro data point, so t 200 Hz gyro rate this means 2 -4 kHz fusion rate. No AVR can do this....

On Thu, Aug 13, 2020 at 2:20 PM beaumr2 notifications@github.com wrote:

So here is hopefully my final question (sorry for bothering you so much). Situation: Pitch and roll is stable, MPU9250 is at rest Move MPU9250 MPU9250 at rest Pitch and roll jump around for a few second after before becoming stable.

I assume it's something about the sampling rate?

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[beaumr2]

Okay. Thank you!!

[kriswiner]

This https://www.tindie.com/products/tleracorp/ladybug-stm32l432-development-board/ should do. Or this https://www.tindie.com/products/tleracorp/dragonfly-stm32l47696-development-board/ .

On Thu, Aug 13, 2020 at 3:01 PM beaumr2 notifications@github.com wrote:

Okay. Thank you!!

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[beaumr2]

Yeah I'm using the latter board linked there

[kriswiner]

OK, you should be seeing fusion rates of several kHz then...

On Thu, Aug 13, 2020 at 3:14 PM beaumr2 notifications@github.com wrote:

Yeah I'm using the latter board linked there

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[beaumr2]

I ended up buying another sensor, exact same vendor and everything: https://smile.amazon.com/gp/product/B01I1J0Z7Y/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

Problem now is no matter what my x-axis accel is zero. You think it could just be a faulty sensor? Everything else is working well

Here's some sample output with me waving it all around. I have it still during calibration

ax = 0.00 ay = -466.49 az = 144.41 mg gx = -52.67 gy = 89.88 gz = -0.03 deg/s Pitch & Roll: -37.52, 1.03 Maximum Pitch & Roll 37.52,22.19 ax = 0.00 ay = -837.89 az = 852.17 mg gx = 30.68 gy = -76.27 gz = 0.13 deg/s Pitch & Roll: -36.36, -9.82 Maximum Pitch & Roll 37.52,22.19 ax = 0.00 ay = -436.52 az = 1437.62 mg gx = -51.30 gy = -103.14 gz = -0.16 deg/s Pitch & Roll: -51.85, 13.69 Maximum Pitch & Roll 51.85,22.19 ax = 0.00 ay = -837.89 az = 578.55 mg gx = 114.14 gy = 249.99 gz = 0.15 deg/s Pitch & Roll: -65.91, 12.87 Maximum Pitch & Roll 65.91,22.19 ax = 0.00 ay = -837.89 az = 1244.32 mg gx = -78.32 gy = 156.17 gz = 0.15 deg/s Pitch & Roll: -11.88, 22.59 Maximum Pitch & Roll 65.91,22.59 ax = 0.00 ay = -837.89 az = -1157.23 mg gx = -71.97 gy = 155.55 gz = 0.11 deg/s Pitch & Roll: -18.38, -14.19 Maximum Pitch & Roll 65.91,22.59 ax = 0.00 ay = -837.89 az = 266.05 mg gx = -11.44 gy = 46.17 gz = -0.03 deg/s Pitch & Roll: -28.08, -27.48 Maximum Pitch & Roll 65.91,27.48 ax = 0.00 ay = -623.29 az = 1225.95 mg gx = -29.97 gy = 211.76 gz = 0.15 deg/s Pitch & Roll: -14.54, 28.25 Maximum Pitch & Roll 65.91,28.25 ax = 0.00 ay = -837.89 az = -582.03 mg gx = 171.13 gy = -73.61 gz = 0.10 deg/s

[kriswiner]

Those boards are usually OK, but I would get my money back. X-axis is busted. What does it show on the self test?

On Fri, Aug 21, 2020 at 12:44 PM beaumr2 notifications@github.com wrote:

I ended up buying another sensor, exact same vendor and everything:

https://smile.amazon.com/gp/product/B01I1J0Z7Y/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

Problem now is no matter what my x-axis accel is zero. You think it could just be a faulty sensor? Everything else is working well

Here's some sample output with me waving it all around. I have it still during calibration

ax = 0.00 ay = -466.49 az = 144.41 mg gx = -52.67 gy = 89.88 gz = -0.03 deg/s Pitch & Roll: -37.52, 1.03 Maximum Pitch & Roll 37.52,22.19 ax = 0.00 ay = -837.89 az = 852.17 mg gx = 30.68 gy = -76.27 gz = 0.13 deg/s Pitch & Roll: -36.36, -9.82 Maximum Pitch & Roll 37.52,22.19 ax = 0.00 ay = -436.52 az = 1437.62 mg gx = -51.30 gy = -103.14 gz = -0.16 deg/s Pitch & Roll: -51.85, 13.69 Maximum Pitch & Roll 51.85,22.19 ax = 0.00 ay = -837.89 az = 578.55 mg gx = 114.14 gy = 249.99 gz = 0.15 deg/s Pitch & Roll: -65.91, 12.87 Maximum Pitch & Roll 65.91,22.19 ax = 0.00 ay = -837.89 az = 1244.32 mg gx = -78.32 gy = 156.17 gz = 0.15 deg/s Pitch & Roll: -11.88, 22.59 Maximum Pitch & Roll 65.91,22.59 ax = 0.00 ay = -837.89 az = -1157.23 mg gx = -71.97 gy = 155.55 gz = 0.11 deg/s Pitch & Roll: -18.38, -14.19 Maximum Pitch & Roll 65.91,22.59 ax = 0.00 ay = -837.89 az = 266.05 mg gx = -11.44 gy = 46.17 gz = -0.03 deg/s Pitch & Roll: -28.08, -27.48 Maximum Pitch & Roll 65.91,27.48 ax = 0.00 ay = -623.29 az = 1225.95 mg gx = -29.97 gy = 211.76 gz = 0.15 deg/s Pitch & Roll: -14.54, 28.25 Maximum Pitch & Roll 65.91,28.25 ax = 0.00 ay = -837.89 az = -582.03 mg gx = 171.13 gy = -73.61 gz = 0.10 deg/s

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[beaumr2]

Yeah I think it's busted. It shows -2000mg every time on the self test. Gotta get a new one

[kriswiner]

Or buy something decent like: https://www.tindie.com/products/onehorse/ultimate-sensor-fusion-solution-mpu9250/

On Fri, Aug 21, 2020 at 1:25 PM beaumr2 notifications@github.com wrote:

Yeah I think it's busted. It shows -2000mg every time on the self test. Gotta get a new one

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[beaumr2]

So I bought that but am now having new problems. Here's my wiring, same as I had it with the old MPU9250:

VCC-> 3V3 GND->GND Pin 29 -> SCL Pin 28 -> SDA Pin 9 -> INT

And I get this error: MPU9250 9-axis motion sensor... MPU9250 I AM 10 I should be 71 Could not connect to MPU9250

Is there any code that needs to change with this new MPU9250?

[beaumr2]

Sorry this is the error, left off the last bit:

MPU9250 9-axis motion sensor... MPU9250 I AM 10 I should be 71 Could not connect to MPU9250: 0x10

[kriswiner]

So you are using a Dragonfly board? I2C is pins 20/21.

What happens when you use an appropriate sketch like this https://github.com/kriswiner/Dragonfly/tree/master/MPU9250Optimized one?

On Sun, Aug 30, 2020 at 5:50 PM beaumr2 notifications@github.com wrote:

So I bought that but am now having new problems. Here's my wiring, same as I had it with the old MPU9250:

VCC-> 3V3 GND->GND Pin 29 -> SCL Pin 28 -> SDA Pin 9 -> INT

And I get this error: MPU9250 9-axis motion sensor... MPU9250 I AM 10 I should be 71 Could not connect to MPU9250

Is there any code that needs to change with this new MPU9250?

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[beaumr2]

I'm using the dragonfly STM32L476. It's works fine with the old MPU9250 I linked but not this one. And yes, I'm using that code

[beaumr2]

3.3V on both SCL and SDA pins

[kriswiner]

Very confused here.

What are your SDA/SCL connections?

Should be drop-dead simple to make this work.

Maybe a picture or sketch to at least make sure you have the sensor board connected properly.

On Sun, Aug 30, 2020 at 6:03 PM beaumr2 notifications@github.com wrote:

3.3V on both SCL and SDA pins

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[beaumr2]

Wiring: Pin 29 -> SCL Pin 28 -> SDA

Sorry it's pretty hard to make out what's in the picture.

[beaumr2]

Here's the full code. Works fine with the old MPU9250 and same wiring. Can't connect to the one you recently linked for some reason

/* MPU9250 Basic Example Code

• MAKE SURE TO PLUG IN MAGNETIC DECLINATION OF YOUR LOCATION

• AND SAVE MAGNETIC CALIBRATION VALUES by: Kris Winer date: May 1, 2016 license: Beerware - Use this code however you'd like. If you find it useful you can buy me a beer some time.

  Demonstrate basic MPU-9250 functionality including parameterizing the register addresses, initializing the sensor, getting properly scaled accelerometer, gyroscope, and magnetometer data out. Addition of 9 DoF sensor fusion using open source Madgwick and Mahony filter algorithms.

  This version uses the MPU9250 interrupt instead of polling and gets up to 13.5 kHz sensor fusion rates using the Madgwick algorithm.

  Sketch runs on the 3.3 V Dragonfly STM32L476 Breakout Board.

  SDA and SCL have 4K7 pull-up resistors (to 3.3V).

  */

include "Wire.h"

define Serial SerialUSB // might not be needed in future

// See also MPU-9250 Register Map and Descriptions, Revision 4.0, RM-MPU-9250A-00, Rev. 1.4, 9/9/2013 for registers not listed in // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map // //Magnetometer Registers

define AK8963_ADDRESS 0x0C

define WHO_AM_I_AK8963 0x00 // should return 0x48

define INFO 0x01

define AK8963_ST1 0x02 // data ready status bit 0

define AK8963_XOUT_L 0x03 // data

define AK8963_XOUT_H 0x04

define AK8963_YOUT_L 0x05

define AK8963_YOUT_H 0x06

define AK8963_ZOUT_L 0x07

define AK8963_ZOUT_H 0x08

define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status bit 2

define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001), self-test (1000) and Fuse ROM (1111) modes on bits 3:0

define AK8963_ASTC 0x0C // Self test control

define AK8963_I2CDIS 0x0F // I2C disable

define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value

define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value

define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value

define SELF_TEST_X_GYRO 0x00

define SELF_TEST_Y_GYRO 0x01

define SELF_TEST_Z_GYRO 0x02

/*#define X_FINE_GAIN 0x03 // [7:0] fine gain

define Y_FINE_GAIN 0x04

define Z_FINE_GAIN 0x05

define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer

define XA_OFFSET_L_TC 0x07

define YA_OFFSET_H 0x08

define YA_OFFSET_L_TC 0x09

define ZA_OFFSET_H 0x0A

define ZA_OFFSET_L_TC 0x0B */

define SELF_TEST_X_ACCEL 0x0D

define SELF_TEST_Y_ACCEL 0x0E

define SELF_TEST_Z_ACCEL 0x0F

define SELF_TEST_A 0x10

define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope

define XG_OFFSET_L 0x14

define YG_OFFSET_H 0x15

define YG_OFFSET_L 0x16

define ZG_OFFSET_H 0x17

define ZG_OFFSET_L 0x18

define SMPLRT_DIV 0x19

define CONFIG 0x1A

define GYRO_CONFIG 0x1B

define ACCEL_CONFIG 0x1C

define ACCEL_CONFIG2 0x1D

define LP_ACCEL_ODR 0x1E

define WOM_THR 0x1F

define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms

define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]

define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms

define FIFO_EN 0x23

define I2C_MST_CTRL 0x24

define I2C_SLV0_ADDR 0x25

define I2C_SLV0_REG 0x26

define I2C_SLV0_CTRL 0x27

define I2C_SLV1_ADDR 0x28

define I2C_SLV1_REG 0x29

define I2C_SLV1_CTRL 0x2A

define I2C_SLV2_ADDR 0x2B

define I2C_SLV2_REG 0x2C

define I2C_SLV2_CTRL 0x2D

define I2C_SLV3_ADDR 0x2E

define I2C_SLV3_REG 0x2F

define I2C_SLV3_CTRL 0x30

define I2C_SLV4_ADDR 0x31

define I2C_SLV4_REG 0x32

define I2C_SLV4_DO 0x33

define I2C_SLV4_CTRL 0x34

define I2C_SLV4_DI 0x35

define I2C_MST_STATUS 0x36

define INT_PIN_CFG 0x37

define INT_ENABLE 0x38

define DMP_INT_STATUS 0x39 // Check DMP interrupt

define INT_STATUS 0x3A

define ACCEL_XOUT_H 0x3B

define ACCEL_XOUT_L 0x3C

define ACCEL_YOUT_H 0x3D

define ACCEL_YOUT_L 0x3E

define ACCEL_ZOUT_H 0x3F

define ACCEL_ZOUT_L 0x40

define TEMP_OUT_H 0x41

define TEMP_OUT_L 0x42

define GYRO_XOUT_H 0x43

define GYRO_XOUT_L 0x44

define GYRO_YOUT_H 0x45

define GYRO_YOUT_L 0x46

define GYRO_ZOUT_H 0x47

define GYRO_ZOUT_L 0x48

define EXT_SENS_DATA_00 0x49

define EXT_SENS_DATA_01 0x4A

define EXT_SENS_DATA_02 0x4B

define EXT_SENS_DATA_03 0x4C

define EXT_SENS_DATA_04 0x4D

define EXT_SENS_DATA_05 0x4E

define EXT_SENS_DATA_06 0x4F

define EXT_SENS_DATA_07 0x50

define EXT_SENS_DATA_08 0x51

define EXT_SENS_DATA_09 0x52

define EXT_SENS_DATA_10 0x53

define EXT_SENS_DATA_11 0x54

define EXT_SENS_DATA_12 0x55

define EXT_SENS_DATA_13 0x56

define EXT_SENS_DATA_14 0x57

define EXT_SENS_DATA_15 0x58

define EXT_SENS_DATA_16 0x59

define EXT_SENS_DATA_17 0x5A

define EXT_SENS_DATA_18 0x5B

define EXT_SENS_DATA_19 0x5C

define EXT_SENS_DATA_20 0x5D

define EXT_SENS_DATA_21 0x5E

define EXT_SENS_DATA_22 0x5F

define EXT_SENS_DATA_23 0x60

define MOT_DETECT_STATUS 0x61

define I2C_SLV0_DO 0x63

define I2C_SLV1_DO 0x64

define I2C_SLV2_DO 0x65

define I2C_SLV3_DO 0x66

define I2C_MST_DELAY_CTRL 0x67

define SIGNAL_PATH_RESET 0x68

define MOT_DETECT_CTRL 0x69

define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP

define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode

define PWR_MGMT_2 0x6C

define DMP_BANK 0x6D // Activates a specific bank in the DMP

define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank

define DMP_REG 0x6F // Register in DMP from which to read or to which to write

define DMP_REG_1 0x70

define DMP_REG_2 0x71

define FIFO_COUNTH 0x72

define FIFO_COUNTL 0x73

define FIFO_R_W 0x74

define WHO_AM_I_MPU9250 0x75 // Should return 0x71

define XA_OFFSET_H 0x77

define XA_OFFSET_L 0x78

define YA_OFFSET_H 0x7A

define YA_OFFSET_L 0x7B

define ZA_OFFSET_H 0x7D

define ZA_OFFSET_L 0x7E

// Define I2C addresses of MPU9250

define ADO 0

if ADO

define MPU9250_ADDRESS 0x69 // Device address when ADO = 1

define AK8963_ADDRESS 0x0C // Address of magnetometer

else

define MPU9250_ADDRESS 0x68 // Device address when ADO = 0

define AK8963_ADDRESS 0x0C // Address of magnetometer

endif

define AHRS true // set to false for basic data read

define SerialDebug true // set to true to get Serial output for debugging

// Set initial input parameters enum Ascale { AFS_2G = 0, AFS_4G, AFS_8G, AFS_16G };

enum Gscale { GFS_250DPS = 0, GFS_500DPS, GFS_1000DPS, GFS_2000DPS };

enum Mscale { MFS_14BITS = 0, // 0.6 mG per LSB MFS_16BITS // 0.15 mG per LSB };

// Specify sensor full scale uint8_t Gscale = GFS_250DPS; uint8_t Ascale = AFS_2G; uint8_t Mscale = MFS_16BITS; // Choose either 14-bit or 16-bit magnetometer resolution uint8_t Mmode = 0x06; // 2 for 8 Hz, 6 for 100 Hz continuous magnetometer data read float aRes, gRes, mRes; // scale resolutions per LSB for the sensors

// Pin definitions int intPin = 9; // When mounted on back pads SDA = 42, SCL = 43, and INT = 41 bool newData = false; uint8_t rawMPU9250Data[14]; uint8_t rawAK8963Data[8];

//int myLed = 13; // green led

int16_t MPU9250Data[7]; // used to read all 14 bytes at once from the MPU9250 accel/gyro int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output float magCalibration[3] = {0, 0, 0}; // Factory mag calibration and mag bias float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}, magBias[3] = {0, 0, 0}, magScale[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer int16_t tempCount; // temperature raw count output float temperature; // Stores the real internal chip temperature in degrees Celsius float SelfTest[6]; // holds results of gyro and accelerometer self test

// global constants for 9 DoF fusion and AHRS (Attitude and Heading Reference System) float GyroMeasError = PI (40.0f / 180.0f); // gyroscope measurement error in rads/s (start at 40 deg/s) float GyroMeasDrift = PI (0.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s) // There is a tradeoff in the beta parameter between accuracy and response speed. // In the original Madgwick study, beta of 0.041 (corresponding to GyroMeasError of 2.7 degrees/s) was found to give optimal accuracy. // However, with this value, the LSM9SD0 response time is about 10 seconds to a stable initial quaternion. // Subsequent changes also require a longish lag time to a stable output, not fast enough for a quadcopter or robot car! // By increasing beta (GyroMeasError) by about a factor of fifteen, the response time constant is reduced to ~2 sec // I haven't noticed any reduction in solution accuracy. This is essentially the I coefficient in a PID control sense; // the bigger the feedback coefficient, the faster the solution converges, usually at the expense of accuracy. // In any case, this is the free parameter in the Madgwick filtering and fusion scheme. float beta = sqrtf(3.0f / 4.0f) GyroMeasError; // compute beta float zeta = sqrtf(3.0f / 4.0f) GyroMeasDrift; // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value

define Kp 2.0f * 5.0f // these are the free parameters in the Mahony filter and fusion scheme, Kp for proportional feedback, Ki for integral

define Ki 0.0f

uint32_t delt_t = 0; // used to control display output rate uint32_t count = 0, sumCount = 0; // used to control display output rate float pitch, yaw, roll; float deltat = 0.0f, sum = 0.0f; // integration interval for both filter schemes uint32_t lastUpdate = 0, firstUpdate = 0; // used to calculate integration interval uint32_t Now = 0; // used to calculate integration interval

float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method

//All measurements in inches, weights in lbs const double WB = 2.5005; //Wheelbase const double TW = 1.868; //Track width const double HH = .4455; //Hub height (aka axle height) const double RH = .642; //Raised height const double W = 97.93; //Total weight const double PW = 48.71; //Passenger weight const double RW = 51.54; //Rear weight const double RWr = 55.65; //Rear weight when raise double CGx = 0; //Center of Gravity from driver's side tire outer edge double CGy = 0; //CoG behind front axle double CGz = 0; //CoG from ground double LRTheta = 0; //Left rollover angle double RRTheta = 0; //Right rollover angle double FRTheta = 0; //Front rollover angle double ARTheta = 0; //Aft (rear) rollover angle

double MaxRoll = 0; double MaxPitch = 0;

define RAD_TO_DEG 57.295779513082320876798154814105 //180 divided by pi

include

LiquidCrystal lcd(8, 7, 5, 4, 3, 2);

const int switchPin = 6; int switchState = 0; int prevSwitchState = 0;

void setup() { Serial.begin(115200); delay(1000); Wire.begin(TWI_PINS_20_21); // set master mode Wire.setClock(400000); // I2C frequency at 400 kHz delay(1000);

// Set up the interrupt pin, it's set as active high, push-pull pinMode(intPin, INPUT); // pinMode(myLed, OUTPUT); // digitalWrite(myLed, LOW); // start with green led on (active LOW)

// Read the WHO_AM_I register, this is a good test of communication Serial.println("MPU9250 9-axis motion sensor..."); byte c = readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250 Serial.print("MPU9250 "); Serial.print("I AM "); Serial.print(c, HEX); Serial.print(" I should be "); Serial.println(0x71, HEX); delay(1000);

if (c == 0x71) // WHO_AM_I should always be 0x68 {
Serial.println("MPU9250 is online...");

MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values
/*Serial.print("x-axis self test: acceleration trim within : "); Serial.print(SelfTest[0],1); Serial.println("% of factory value");
Serial.print("y-axis self test: acceleration trim within : "); Serial.print(SelfTest[1],1); Serial.println("% of factory value");
Serial.print("z-axis self test: acceleration trim within : "); Serial.print(SelfTest[2],1); Serial.println("% of factory value");
Serial.print("x-axis self test: gyration trim within : "); Serial.print(SelfTest[3],1); Serial.println("% of factory value");
Serial.print("y-axis self test: gyration trim within : "); Serial.print(SelfTest[4],1); Serial.println("% of factory value");
Serial.print("z-axis self test: gyration trim within : "); Serial.print(SelfTest[5],1); Serial.println("% of factory value");
delay(1000);
*/

// get sensor resolutions, only need to do this once getAres(); getGres(); getMres();

calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers /accelBias[0] = 0; accelBias[1] = 0; accelBias[2] = 1; / gyroBias[0] = -4.82; gyroBias[1] = -10.18; gyroBias[2] = -.64;/ //USE THIS instead of calibrating accelerometer and gyroscope every time //Because the Jeep shaking while running will affect it. //So calibrate once while on level ground as it sits in the Jeep then store those values Serial.println("accel biases (mg)"); Serial.println(1000.accelBias[0]); Serial.println(1000.accelBias[1]); Serial.println(1000.accelBias[2]); Serial.println("gyro biases (dps)"); Serial.println(gyroBias[0]); Serial.println(gyroBias[1]); Serial.println(gyroBias[2]); delay(1000);

initMPU9250(); Serial.println("MPU9250 initialized for active data mode...."); // Initialize device for active mode read of acclerometer, gyroscope, and temperature

// Read the WHO_AM_I register of the magnetometer, this is a good test of communication byte d = readByte(AK8963_ADDRESS, WHO_AM_I_AK8963); // Read WHO_AM_I register for AK8963 Serial.print("AK8963 "); Serial.print("I AM "); Serial.print(d, HEX); Serial.print(" I should be "); Serial.println(0x48, HEX); delay(1000);

// Get magnetometer calibration from AK8963 ROM initAK8963(magCalibration); Serial.println("AK8963 initialized for active data mode...."); // Initialize device for active mode read of magnetometer

magcalMPU9250(magBias, magScale); //Serial.println("AK8963 mag biases (mG)"); Serial.println(magBias[0]); Serial.println(magBias[1]); Serial.println(magBias[2]); //Serial.println("AK8963 mag scale (mG)"); Serial.println(magScale[0]); Serial.println(magScale[1]); Serial.println(magScale[2]); delay(2000); // add delay to see results before serial spew of data

if(SerialDebug) { / Serial.println("Calibration values: "); Serial.print("X-Axis sensitivity adjustment value "); Serial.println(magCalibration[0], 2); Serial.print("Y-Axis sensitivity adjustment value "); Serial.println(magCalibration[1], 2); Serial.print("Z-Axis sensitivity adjustment value "); Serial.println(magCalibration[2], 2); / attachInterrupt(intPin, myinthandler, RISING); // define interrupt for INT pin output of MPU9250 }

} else { Serial.print("Could not connect to MPU9250: 0x"); Serial.println(c, HEX); while(1) ; // Loop forever if communication doesn't happen }

CGx = PW TW / W; CGy = RW WB / W; CGz = HH + ((RWr - RW) / W) ((sqrt((sq(WB))-(sq(RH)))WB) / RH);

Serial.print("Your x center of gravity is: "); Serial.println(CGx); Serial.print("Your y center of gravity is: "); Serial.println(CGy); Serial.print("Your z center of gravity is: "); Serial.println(CGz);

LRTheta = atan2(CGx, CGz) RAD_TO_DEG; RRTheta = atan2(TW-CGx, CGz) RAD_TO_DEG; FRTheta = atan2(CGy, CGz) RAD_TO_DEG; ARTheta = atan2(WB-CGy, CGz) RAD_TO_DEG;

lcd.begin(16, 2); lcd.setCursor(0, 0); lcd.print("Left rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(LRTheta); delay(2000); lcd.clear(); lcd.setCursor(0, 0); lcd.print("Right rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(RRTheta); delay(2000); lcd.clear(); lcd.setCursor(0, 0); lcd.print("Front rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(FRTheta); delay(2000); lcd.clear(); lcd.setCursor(0, 0); lcd.print("Rear rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(ARTheta); delay(2000); lcd.clear(); pinMode(switchPin, INPUT); }

void loop() {
// If intPin goes high, all data registers have new data if(newData == true) { // On interrupt, read data newData = false; // reset newData flag readMPU9250Data(MPU9250Data); // INT cleared on any read // readAccelData(accelCount); // Read the x/y/z adc values

// Now we'll calculate the accleration value into actual g's
ax = (float)MPU9250Data[0]*aRes - accelBias[0];  // get actual g value, this depends on scale being set
ay = (float)MPU9250Data[1]*aRes - accelBias[1];   
az = (float)MPU9250Data[2]*aRes - accelBias[2];  

// readGyroData(gyroCount); // Read the x/y/z adc values

// Calculate the gyro value into actual degrees per second
gx = (float)MPU9250Data[4]*gRes;  // get actual gyro value, this depends on scale being set
gy = (float)MPU9250Data[5]*gRes;  
gz = (float)MPU9250Data[6]*gRes;   

readAK8963Data(magCount);  // Read the x/y/z adc values

// Calculate the magnetometer values in milliGauss
// Include factory calibration per data sheet and user environmental corrections
mx = (float)magCount[0]*mRes*magCalibration[0] - magBias[0];  // get actual magnetometer value, this depends on scale being set
my = (float)magCount[1]*mRes*magCalibration[1] - magBias[1];  
mz = (float)magCount[2]*mRes*magCalibration[2] - magBias[2];  
mx *= magScale[0];
my *= magScale[1];
mz *= magScale[2];  

}

Now = micros(); deltat = ((Now - lastUpdate)/1000000.0f); // set integration time by time elapsed since last filter update lastUpdate = Now;

sum += deltat; // sum for averaging filter update rate sumCount++;

// Sensors x (y)-axis of the accelerometer/gyro is aligned with the y (x)-axis of the magnetometer;

// the magnetometer z-axis (+ down) is misaligned with z-axis (+ up) of accelerometer and gyro! // We have to make some allowance for this orientation mismatch in feeding the output to the quaternion filter. // We will assume that +y accel/gyro is North, then x accel/gyro is East. So if we want te quaternions properly aligned // we need to feed into the madgwick function Ay, Ax, -Az, Gy, Gx, -Gz, Mx, My, and Mz. But because gravity is by convention // positive down, we need to invert the accel data, so we pass -Ay, -Ax, Az, Gy, Gx, -Gz, Mx, My, and Mz into the Madgwick // function to get North along the accel +y-axis, East along the accel +x-axis, and Down along the accel -z-axis. // This orientation choice can be modified to allow any convenient (non-NED) orientation convention. // This is ok by aircraft orientation standards!
// Pass gyro rate as rad/s MadgwickQuaternionUpdate(-ay, -ax, az, gyPI/180.0f, gxPI/180.0f, -gzPI/180.0f, mx, my, mz); // if(passThru)MahonyQuaternionUpdate(-ay, -ax, az, gyPI/180.0f, gxPI/180.0f, -gzPI/180.0f, mx, my, mz);

// Serial print and/or display at 1 s rate independent of data rates
delt_t = millis() - count;
if (delt_t > 500) { // update serial once per half-second independent of read rate

if(SerialDebug) {

Serial.print("ax = "); Serial.print((int)1000*ax);  
Serial.print(" ay = "); Serial.print((int)1000*ay); 
Serial.print(" az = "); Serial.print((int)1000*az); Serial.println(" mg");
Serial.print("gx = "); Serial.print( gx, 2); 
Serial.print(" gy = "); Serial.print( gy, 2); 
Serial.print(" gz = "); Serial.print( gz, 2); Serial.println(" deg/s");
/*
Serial.print("mx = "); Serial.print( (int)mx ); 
Serial.print(" my = "); Serial.print( (int)my ); 
Serial.print(" mz = "); Serial.print( (int)mz ); Serial.println(" mG");

Serial.print("q0 = "); Serial.print(q[0]);
Serial.print(" qx = "); Serial.print(q[1]); 
Serial.print(" qy = "); Serial.print(q[2]); 
Serial.print(" qz = "); Serial.println(q[3]); 

*/ // tempCount = readTempData(); // Read the gyro adc values temperature = ((float) MPU9250Data[3]) / 333.87 + 21.0; // Gyro chip temperature in degrees Centigrade // Print temperature in degrees Centigrade
//Serial.print("Gyro temperature is "); Serial.print(temperature, 1); Serial.println(" degrees C"); // Print T values to tenths of s degree C }

// Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation. // In this coordinate system, the positive z-axis is down toward Earth. // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination, looking down on the sensor positive yaw is counterclockwise. // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative. // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll. // These arise from the definition of the homogeneous rotation matrix constructed from quaternions. // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be // applied in the correct order which for this configuration is yaw, pitch, and then roll. // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links. //Software AHRS: yaw = atan2f(2.0f (q[1] q[2] + q[0] q[3]), q[0] q[0] + q[1] q[1] - q[2] q[2] - q[3] q[3]);
pitch = -asinf(2.0f (q[1] q[3] - q[0] q[2])); roll = atan2f(2.0f (q[0] q[1] + q[2] q[3]), q[0] q[0] - q[1] q[1] - q[2] q[2] + q[3] q[3]); pitch = 180.0f / PI; yaw = 180.0f / PI; yaw += 0.13f; // .13 is the mag dec for Missouri Example: Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04 so you would use 13.8 if(yaw < 0) yaw += 360.0f; // Ensure yaw stays between 0 and 360 roll = 180.0f / PI;

if(SerialDebug) {
Serial.print("Pitch & Roll: ");
//Serial.print(yaw, 2);
//Serial.print(", ");
Serial.print(pitch, 2);
Serial.print(", ");
Serial.println(roll, 2);

// Serial.print("rate = "); Serial.print((float)sumCount/sum, 2); Serial.println(" Hz");

if(abs(pitch) > MaxPitch && millis() > 100000) { MaxPitch = abs(pitch); } else if (abs(roll) > MaxRoll && millis() > 100000) { MaxRoll = abs(roll); } else {} Serial.println("Maximum Pitch & Roll"); Serial.print(MaxPitch, 2); Serial.print(","); Serial.println(MaxRoll, 2); }

count = millis(); 
sumCount = 0;
sum = 0;    
}

lcd.setCursor(0, 0); lcd.print("Pitch: "); lcd.print(pitch); lcd.setCursor(0, 1); lcd.print("Roll: "); lcd.print(roll); delay(100); switchState = digitalRead(switchPin); if (switchState != prevSwitchState) { if (switchState == LOW) { lcd.clear(); lcd.setCursor(0,0); lcd.print("Max Pitch:"); lcd.print(MaxPitch); lcd.setCursor(0,1); lcd.print("Max Roll:"); lcd.print(MaxRoll); delay(5000); } } prevSwitchState = switchState; }

//=================================================================================================================== //====== Set of useful function to access acceleration. gyroscope, magnetometer, and temperature data //===================================================================================================================

void myinthandler() { uint8_t subAddress = ACCEL_XOUT_H;

Wire.transfer(MPU9250_ADDRESS, &subAddress, 1, &rawMPU9250Data[0], 14, true, mywirehandler1); }

void mywirehandler1(uint8_t status) { uint8_t subAddress = AK8963_ST1;

Wire.transfer(AK8963_ADDRESS, &subAddress, 1, &rawAK8963Data[0], 8, true, mywirehandler2); }

void mywirehandler2(uint8_t status) { newData = true; }

void getMres() { switch (Mscale) { // Possible magnetometer scales (and their register bit settings) are: // 14 bit resolution (0) and 16 bit resolution (1) case MFS_14BITS: mRes = 10.4912./8190.; // Proper scale to return milliGauss break; case MFS_16BITS: mRes = 10.4912./32760.0; // Proper scale to return milliGauss break; } }

void getGres() { switch (Gscale) { // Possible gyro scales (and their register bit settings) are: // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11). // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: case GFS_250DPS: gRes = 250.0/32768.0; break; case GFS_500DPS: gRes = 500.0/32768.0; break; case GFS_1000DPS: gRes = 1000.0/32768.0; break; case GFS_2000DPS: gRes = 2000.0/32768.0; break; } }

void getAres() { switch (Ascale) { // Possible accelerometer scales (and their register bit settings) are: // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11). // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: case AFS_2G: aRes = 2.0/32768.0; break; case AFS_4G: aRes = 4.0/32768.0; break; case AFS_8G: aRes = 8.0/32768.0; break; case AFS_16G: aRes = 16.0/32768.0; break; } }

void readMPU9250Data(int16_t * destination) { destination[0] = ((int16_t)rawMPU9250Data[0] << 8) | rawMPU9250Data[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawMPU9250Data[2] << 8) | rawMPU9250Data[3] ;
destination[2] = ((int16_t)rawMPU9250Data[4] << 8) | rawMPU9250Data[5] ; destination[3] = ((int16_t)rawMPU9250Data[6] << 8) | rawMPU9250Data[7] ;
destination[4] = ((int16_t)rawMPU9250Data[8] << 8) | rawMPU9250Data[9] ;
destination[5] = ((int16_t)rawMPU9250Data[10] << 8) | rawMPU9250Data[11] ;
destination[6] = ((int16_t)rawMPU9250Data[12] << 8) | rawMPU9250Data[13] ;

}

void readAK8963Data(int16_t * destination) { if(rawAK8963Data[0] & 0x01) { // wait for magnetometer data ready bit to be set uint8_t c = rawAK8963Data[7]; // End data read by reading ST2 register if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data destination[0] = ((int16_t)rawAK8963Data[2] << 8) | rawAK8963Data[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawAK8963Data[4] << 8) | rawAK8963Data[3] ; // Data stored as little Endian destination[2] = ((int16_t)rawAK8963Data[6] << 8) | rawAK8963Data[5] ; } } }

void readAccelData(int16_t * destination) { uint8_t rawData[6]; // x/y/z accel register data stored here readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array destination[0] = ((int16_t)rawData[0] << 8) | rawData[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawData[2] << 8) | rawData[3] ;
destination[2] = ((int16_t)rawData[4] << 8) | rawData[5] ; }

void readGyroData(int16_t * destination) { uint8_t rawData[6]; // x/y/z gyro register data stored here readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array destination[0] = ((int16_t)rawData[0] << 8) | rawData[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawData[2] << 8) | rawData[3] ;
destination[2] = ((int16_t)rawData[4] << 8) | rawData[5] ; }

void readMagData(int16_t * destination) { uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array uint8_t c = rawData[6]; // End data read by reading ST2 register if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data destination[0] = ((int16_t)rawData[1] << 8) | rawData[0] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawData[3] << 8) | rawData[2] ; // Data stored as little Endian destination[2] = ((int16_t)rawData[5] << 8) | rawData[4] ; } } }

int16_t readTempData() { uint8_t rawData[2]; // x/y/z gyro register data stored here readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array return ((int16_t)rawData[0] << 8) | rawData[1] ; // Turn the MSB and LSB into a 16-bit value }

void initAK8963(float * destination) { // First extract the factory calibration for each magnetometer axis uint8_t rawData[3]; // x/y/z gyro calibration data stored here writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
delay(10); writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode delay(10); readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values destination[0] = (float)(rawData[0] - 128)/256. + 1.; // Return x-axis sensitivity adjustment values, etc. destination[1] = (float)(rawData[1] - 128)/256. + 1.;
destination[2] = (float)(rawData[2] - 128)/256. + 1.; writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
delay(10); // Configure the magnetometer for continuous read and highest resolution // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register, // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR delay(10); }

void initMPU9250() {
// wake up device writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors delay(100); // Wait for all registers to reset

// get stable time source writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Auto select clock source to be PLL gyroscope reference if ready else delay(200);

// Configure Gyro and Thermometer // Disable FSYNC and set thermometer and gyro bandwidth to 41 and 42 Hz, respectively; // minimum delay time for this setting is 5.9 ms, which means sensor fusion update rates cannot // be higher than 1 / 0.0059 = 170 Hz // DLPF_CFG = bits 2:0 = 011; this limits the sample rate to 1000 Hz for both // With the MPU9250, it is possible to get gyro sample rates of 32 kHz (!), 8 kHz, or 1 kHz writeByte(MPU9250_ADDRESS, CONFIG, 0x03);

// Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV) writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Use a 1000 Hz rate; a rate consistent with the filter update rate // determined inset in CONFIG above

// Set gyroscope full scale range // Range selects FS_SEL and GFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG); // get current GYRO_CONFIG register value // c = c & ~0xE0; // Clear self-test bits [7:5] c = c & ~0x03; // Clear Fchoice bits [1:0] c = c & ~0x18; // Clear GS bits [4:3] c = c | Gscale << 3; // Set full scale range for the gyro // c =| 0x00; // Set Fchoice for the gyro to 11 by writing its inverse to bits 1:0 of GYRO_CONFIG writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c ); // Write new GYRO_CONFIG value to register

// Set accelerometer full-scale range configuration c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG); // get current ACCEL_CONFIG register value // c = c & ~0xE0; // Clear self-test bits [7:5] c = c & ~0x18; // Clear AFS bits [4:3] c = c | Ascale << 3; // Set full scale range for the accelerometer writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c); // Write new ACCEL_CONFIG register value

// Set accelerometer sample rate configuration // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2); // get current ACCEL_CONFIG2 register value c = c & ~0x0F; // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
c = c | 0x03; // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c); // Write new ACCEL_CONFIG2 register value

// The accelerometer, gyro, and thermometer are set to 1 kHz sample rates

// Configure Interrupts and Bypass Enable // Set interrupt pin active high, push-pull, hold interrupt pin level HIGH until interrupt cleared, // clear on read of INT_STATUS, and enable I2C_BYPASS_EN so additional chips // can join the I2C bus and all can be controlled by the Arduino as master // writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x12); // INT is 50 microsecond pulse and any read to clear
writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt delay(100); }

void magcalMPU9250(float dest1, float dest2) { uint16_t ii = 0, sample_count = 0; int32_t mag_bias[3] = {0, 0, 0}, mag_scale[3] = {0, 0, 0}; int16_t mag_max[3] = {-32767, -32767, -32767}, mag_min[3] = {32767, 32767, 32767}, mag_temp[3] = {0, 0, 0};

//Serial.println("Mag Calibration: Wave device in a figure eight until done!"); //delay(4000); //COMMENTED THE ABOVE 2 LINES OUT BECAUSE NO NEED FOR MAG IF NOT USING YAW

// shoot for ~fifteen seconds of mag data if(Mmode == 0x02) sample_count = 128; // at 8 Hz ODR, new mag data is available every 125 ms if(Mmode == 0x06) sample_count = 1500; // at 100 Hz ODR, new mag data is available every 10 ms for(ii = 0; ii < sample_count; ii++) { readMagData(mag_temp); // Read the mag data
for (int jj = 0; jj < 3; jj++) { if(mag_temp[jj] > mag_max[jj]) mag_max[jj] = mag_temp[jj]; if(mag_temp[jj] < mag_min[jj]) mag_min[jj] = mag_temp[jj]; } if(Mmode == 0x02) delay(135); // at 8 Hz ODR, new mag data is available every 125 ms if(Mmode == 0x06) delay(12); // at 100 Hz ODR, new mag data is available every 10 ms }

// Serial.println("mag x min/max:"); Serial.println(mag_max[0]); Serial.println(mag_min[0]); // Serial.println("mag y min/max:"); Serial.println(mag_max[1]); Serial.println(mag_min[1]); // Serial.println("mag z min/max:"); Serial.println(mag_max[2]); Serial.println(mag_min[2]);

// Get hard iron correction
mag_bias[0]  = (mag_max[0] + mag_min[0])/2;  // get average x mag bias in counts
mag_bias[1]  = (mag_max[1] + mag_min[1])/2;  // get average y mag bias in counts
mag_bias[2]  = (mag_max[2] + mag_min[2])/2;  // get average z mag bias in counts

dest1[0] = (float) mag_bias[0]*mRes*magCalibration[0];  // save mag biases in G for main program
dest1[1] = (float) mag_bias[1]*mRes*magCalibration[1];   
dest1[2] = (float) mag_bias[2]*mRes*magCalibration[2];  

// Get soft iron correction estimate
mag_scale[0]  = (mag_max[0] - mag_min[0])/2;  // get average x axis max chord length in counts
mag_scale[1]  = (mag_max[1] - mag_min[1])/2;  // get average y axis max chord length in counts
mag_scale[2]  = (mag_max[2] - mag_min[2])/2;  // get average z axis max chord length in counts

float avg_rad = mag_scale[0] + mag_scale[1] + mag_scale[2];
avg_rad /= 3.0;

dest2[0] = avg_rad/((float)mag_scale[0]);
dest2[1] = avg_rad/((float)mag_scale[1]);
dest2[2] = avg_rad/((float)mag_scale[2]);

//Serial.println("Mag Calibration done!"); }

// Function which accumulates gyro and accelerometer data after device initialization. It calculates the average // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers. void calibrateMPU9250(float dest1, float dest2) {
uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data uint16_t ii, packet_count, fifo_count; int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};

// reset device writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device delay(100);

// get stable time source; Auto select clock source to be PLL gyroscope reference if ready // else use the internal oscillator, bits 2:0 = 001 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00); delay(200);

// Configure device for bias calculation writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP delay(15);

// Configure MPU6050 gyro and accelerometer for bias calculation writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity

uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec uint16_t accelsensitivity = 16384; // = 16384 LSB/g

// Configure FIFO to capture accelerometer and gyro data for bias calculation

writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9150) delay(40); // accumulate 40 samples in 40 milliseconds = 480 bytes

// At end of sample accumulation, turn off FIFO sensor read writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count fifo_count = ((uint16_t)data[0] << 8) | data[1]; packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging

for (ii = 0; ii < packet_count; ii++) { int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0}; readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ; accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ;
gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ; gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ; gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;

accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases
accel_bias[1] += (int32_t) accel_temp[1];
accel_bias[2] += (int32_t) accel_temp[2];
gyro_bias[0]  += (int32_t) gyro_temp[0];
gyro_bias[1]  += (int32_t) gyro_temp[1];
gyro_bias[2]  += (int32_t) gyro_temp[2];

} accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases accel_bias[1] /= (int32_t) packet_count; accel_bias[2] /= (int32_t) packet_count; gyro_bias[0] /= (int32_t) packet_count; gyro_bias[1] /= (int32_t) packet_count; gyro_bias[2] /= (int32_t) packet_count;

if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation else {accel_bias[2] += (int32_t) accelsensitivity;}

// Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup data[0] = (-gyro_bias[0]/4 >> 8) & 0xFF; // Divide by 4 to get 32.9 LSB per deg/s to conform to expected bias input format data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF; data[3] = (-gyro_bias[1]/4) & 0xFF; data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF; data[5] = (-gyro_bias[2]/4) & 0xFF;

// Push gyro biases to hardware registers writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]); writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]); writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]); writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]); writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]); writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);

// Output scaled gyro biases for display in the main program dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity;
dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity; dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;

// Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that // the accelerometer biases calculated above must be divided by 8.

int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values accel_bias_reg[0] = (int32_t) (((int16_t)data[0] << 8) | data[1]); readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]); accel_bias_reg[1] = (int32_t) (((int16_t)data[0] << 8) | data[1]); readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]); accel_bias_reg[2] = (int32_t) (((int16_t)data[0] << 8) | data[1]);

uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis

for(ii = 0; ii < 3; ii++) { if((accel_bias_reg[ii] & mask)) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit }

// Construct total accelerometer bias, including calculated average accelerometer bias from above accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale) accel_bias_reg[1] -= (accel_bias[1]/8); accel_bias_reg[2] -= (accel_bias[2]/8);

data[0] = (accel_bias_reg[0] >> 8) & 0xFF; data[1] = (accel_bias_reg[0]) & 0xFF; data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[2] = (accel_bias_reg[1] >> 8) & 0xFF; data[3] = (accel_bias_reg[1]) & 0xFF; data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[4] = (accel_bias_reg[2] >> 8) & 0xFF; data[5] = (accel_bias_reg[2]) & 0xFF; data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers

// Apparently this is not working for the acceleration biases in the MPU-9250 // Are we handling the temperature correction bit properly? // Push accelerometer biases to hardware registers // writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]); // writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]); // writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]); // writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]); // writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]); // writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);

// Output scaled accelerometer biases for display in the main program dest2[0] = (float)accel_bias[0]/(float)accelsensitivity; dest2[1] = (float)accel_bias[1]/(float)accelsensitivity; dest2[2] = (float)accel_bias[2]/(float)accelsensitivity; }

// Accelerometer and gyroscope self test; check calibration wrt factory settings void MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass { uint8_t rawData[6] = {0, 0, 0, 0, 0, 0}; uint8_t selfTest[6]; int32_t gAvg[3] = {0}, aAvg[3] = {0}, aSTAvg[3] = {0}, gSTAvg[3] = {0}; float factoryTrim[6]; uint8_t FS = 0;

writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz writeByte(MPU9250_ADDRESS, GYRO_CONFIG, FS<<3); // Set full scale range for the gyro to 250 dps writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, FS<<3); // Set full scale range for the accelerometer to 2 g

for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer

readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;

readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]);       // Read the six raw data registers sequentially into data array

gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; }

for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings aAvg[ii] /= 200; gAvg[ii] /= 200; }

// Configure the accelerometer for self-test writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s delay(25); // Delay a while to let the device stabilize

for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer

readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;

readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]);  // Read the six raw data registers sequentially into data array

gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; }

for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings aSTAvg[ii] /= 200; gSTAvg[ii] /= 200; }

// Configure the gyro and accelerometer for normal operation writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
delay(25); // Delay a while to let the device stabilize

// Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results

// Retrieve factory self-test value from self-test code reads factoryTrim[0] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation factoryTrim[1] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation factoryTrim[2] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation factoryTrim[3] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation factoryTrim[4] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation factoryTrim[5] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation

// Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response // To get percent, must multiply by 100 for (int i = 0; i < 3; i++) { destination[i] = 100.0((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i] - 100.; // Report percent differences destination[i+3] = 100.0((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3] - 100.; // Report percent differences }

}

// I2C read/write functions for the MPU9250 sensors

    void writeByte(uint8_t address, uint8_t subAddress, uint8_t data) {
    uint8_t temp[2];
    temp[0] = subAddress;
    temp[1] = data;
    Wire.transfer(address, &temp[0], 2, NULL, 0); 
    }

    uint8_t readByte(uint8_t address, uint8_t subAddress) {
    uint8_t temp[1];
    Wire.transfer(address, &subAddress, 1, &temp[0], 1);
    return temp[0];
    }

    void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) {
    Wire.transfer(address, &subAddress, 1, dest, count); 
    }

[kriswiner]

Wow, just wow. What the heck is that mess?

Do you know they make machined pin headers like this https://www.peconnectors.com/male-pin-headers-breakaway/ that you can use to solder to the breakout board? Probably get these on Sparkfun or Adafruit too.

Sticking wires into the PTHs of the board is not going to do it.

They make female versions so you could mount the board like this https://github.com/kriswiner/IIS3DWB.

Or at least you could use a breadboard like this https://github.com/kriswiner/LSM6DSO.

What you have there is a rats nest that will never work, or never work reliably as you are demonstrating....

On Sun, Aug 30, 2020 at 6:12 PM beaumr2 notifications@github.com wrote:

Here's the full code. Works fine with the old MPU9250 and same wiring. Can't connect to the one you recently linked for some reason

/ MPU9250 Basic Example Code

• MAKE SURE TO PLUG IN MAGNETIC DECLINATION OF YOUR LOCATION
• AND SAVE MAGNETIC CALIBRATION VALUES by: Kris Winer date: May 1, 2016 license: Beerware - Use this code however you'd like. If you find it useful you can buy me a beer some time.

Demonstrate basic MPU-9250 functionality including parameterizing the register addresses, initializing the sensor, getting properly scaled accelerometer, gyroscope, and magnetometer data out. Addition of 9 DoF sensor fusion using open source Madgwick and Mahony filter algorithms.

This version uses the MPU9250 interrupt instead of polling and gets up to 13.5 kHz sensor fusion rates using the Madgwick algorithm.

Sketch runs on the 3.3 V Dragonfly STM32L476 Breakout Board.

SDA and SCL have 4K7 pull-up resistors (to 3.3V).

*/

include "Wire.h"

define Serial SerialUSB // might not be needed in future

// See also MPU-9250 Register Map and Descriptions, Revision 4.0, RM-MPU-9250A-00, Rev. 1.4, 9/9/2013 for registers not listed in // above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map // //Magnetometer Registers

define AK8963_ADDRESS 0x0C

define WHO_AM_I_AK8963 0x00 // should return 0x48

define INFO 0x01

define AK8963_ST1 0x02 // data ready status bit 0

define AK8963_XOUT_L 0x03 // data

define AK8963_XOUT_H 0x04

define AK8963_YOUT_L 0x05

define AK8963_YOUT_H 0x06

define AK8963_ZOUT_L 0x07

define AK8963_ZOUT_H 0x08

define AK8963_ST2 0x09 // Data overflow bit 3 and data read error status

bit 2

define AK8963_CNTL 0x0A // Power down (0000), single-measurement (0001),

self-test (1000) and Fuse ROM (1111) modes on bits 3:0

define AK8963_ASTC 0x0C // Self test control

define AK8963_I2CDIS 0x0F // I2C disable

define AK8963_ASAX 0x10 // Fuse ROM x-axis sensitivity adjustment value

define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value

define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value

define SELF_TEST_X_GYRO 0x00

define SELF_TEST_Y_GYRO 0x01

define SELF_TEST_Z_GYRO 0x02

/*#define X_FINE_GAIN 0x03 // [7:0] fine gain

define Y_FINE_GAIN 0x04

define Z_FINE_GAIN 0x05

define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer

define XA_OFFSET_L_TC 0x07

define YA_OFFSET_H 0x08

define YA_OFFSET_L_TC 0x09

define ZA_OFFSET_H 0x0A

define ZA_OFFSET_L_TC 0x0B */

define SELF_TEST_X_ACCEL 0x0D

define SELF_TEST_Y_ACCEL 0x0E

define SELF_TEST_Z_ACCEL 0x0F

define SELF_TEST_A 0x10

define XG_OFFSET_H 0x13 // User-defined trim values for gyroscope

define XG_OFFSET_L 0x14

define YG_OFFSET_H 0x15

define YG_OFFSET_L 0x16

define ZG_OFFSET_H 0x17

define ZG_OFFSET_L 0x18

define SMPLRT_DIV 0x19

define CONFIG 0x1A

define GYRO_CONFIG 0x1B

define ACCEL_CONFIG 0x1C

define ACCEL_CONFIG2 0x1D

define LP_ACCEL_ODR 0x1E

define WOM_THR 0x1F

define MOT_DUR 0x20 // Duration counter threshold for motion interrupt

generation, 1 kHz rate, LSB = 1 ms

define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]

define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion

interrupt generation, 16 Hz rate, LSB = 64 ms

define FIFO_EN 0x23

define I2C_MST_CTRL 0x24

define I2C_SLV0_ADDR 0x25

define I2C_SLV0_REG 0x26

define I2C_SLV0_CTRL 0x27

define I2C_SLV1_ADDR 0x28

define I2C_SLV1_REG 0x29

define I2C_SLV1_CTRL 0x2A

define I2C_SLV2_ADDR 0x2B

define I2C_SLV2_REG 0x2C

define I2C_SLV2_CTRL 0x2D

define I2C_SLV3_ADDR 0x2E

define I2C_SLV3_REG 0x2F

define I2C_SLV3_CTRL 0x30

define I2C_SLV4_ADDR 0x31

define I2C_SLV4_REG 0x32

define I2C_SLV4_DO 0x33

define I2C_SLV4_CTRL 0x34

define I2C_SLV4_DI 0x35

define I2C_MST_STATUS 0x36

define INT_PIN_CFG 0x37

define INT_ENABLE 0x38

define DMP_INT_STATUS 0x39 // Check DMP interrupt

define INT_STATUS 0x3A

define ACCEL_XOUT_H 0x3B

define ACCEL_XOUT_L 0x3C

define ACCEL_YOUT_H 0x3D

define ACCEL_YOUT_L 0x3E

define ACCEL_ZOUT_H 0x3F

define ACCEL_ZOUT_L 0x40

define TEMP_OUT_H 0x41

define TEMP_OUT_L 0x42

define GYRO_XOUT_H 0x43

define GYRO_XOUT_L 0x44

define GYRO_YOUT_H 0x45

define GYRO_YOUT_L 0x46

define GYRO_ZOUT_H 0x47

define GYRO_ZOUT_L 0x48

define EXT_SENS_DATA_00 0x49

define EXT_SENS_DATA_01 0x4A

define EXT_SENS_DATA_02 0x4B

define EXT_SENS_DATA_03 0x4C

define EXT_SENS_DATA_04 0x4D

define EXT_SENS_DATA_05 0x4E

define EXT_SENS_DATA_06 0x4F

define EXT_SENS_DATA_07 0x50

define EXT_SENS_DATA_08 0x51

define EXT_SENS_DATA_09 0x52

define EXT_SENS_DATA_10 0x53

define EXT_SENS_DATA_11 0x54

define EXT_SENS_DATA_12 0x55

define EXT_SENS_DATA_13 0x56

define EXT_SENS_DATA_14 0x57

define EXT_SENS_DATA_15 0x58

define EXT_SENS_DATA_16 0x59

define EXT_SENS_DATA_17 0x5A

define EXT_SENS_DATA_18 0x5B

define EXT_SENS_DATA_19 0x5C

define EXT_SENS_DATA_20 0x5D

define EXT_SENS_DATA_21 0x5E

define EXT_SENS_DATA_22 0x5F

define EXT_SENS_DATA_23 0x60

define MOT_DETECT_STATUS 0x61

define I2C_SLV0_DO 0x63

define I2C_SLV1_DO 0x64

define I2C_SLV2_DO 0x65

define I2C_SLV3_DO 0x66

define I2C_MST_DELAY_CTRL 0x67

define SIGNAL_PATH_RESET 0x68

define MOT_DETECT_CTRL 0x69

define USER_CTRL 0x6A // Bit 7 enable DMP, bit 3 reset DMP

define PWR_MGMT_1 0x6B // Device defaults to the SLEEP mode

define PWR_MGMT_2 0x6C

define DMP_BANK 0x6D // Activates a specific bank in the DMP

define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start

address in specified DMP bank

define DMP_REG 0x6F // Register in DMP from which to read or to which to

write

define DMP_REG_1 0x70

define DMP_REG_2 0x71

define FIFO_COUNTH 0x72

define FIFO_COUNTL 0x73

define FIFO_R_W 0x74

define WHO_AM_I_MPU9250 0x75 // Should return 0x71

define XA_OFFSET_H 0x77

define XA_OFFSET_L 0x78

define YA_OFFSET_H 0x7A

define YA_OFFSET_L 0x7B

define ZA_OFFSET_H 0x7D

define ZA_OFFSET_L 0x7E

// Define I2C addresses of MPU9250

define ADO 0

if ADO

define MPU9250_ADDRESS 0x69 // Device address when ADO = 1

define AK8963_ADDRESS 0x0C // Address of magnetometer

else

define MPU9250_ADDRESS 0x68 // Device address when ADO = 0

define AK8963_ADDRESS 0x0C // Address of magnetometer

endif

define AHRS true // set to false for basic data read

define SerialDebug true // set to true to get Serial output for debugging

// Set initial input parameters enum Ascale { AFS_2G = 0, AFS_4G, AFS_8G, AFS_16G };

enum Gscale { GFS_250DPS = 0, GFS_500DPS, GFS_1000DPS, GFS_2000DPS };

enum Mscale { MFS_14BITS = 0, // 0.6 mG per LSB MFS_16BITS // 0.15 mG per LSB };

// Specify sensor full scale uint8_t Gscale = GFS_250DPS; uint8_t Ascale = AFS_2G; uint8_t Mscale = MFS_16BITS; // Choose either 14-bit or 16-bit magnetometer resolution uint8_t Mmode = 0x06; // 2 for 8 Hz, 6 for 100 Hz continuous magnetometer data read float aRes, gRes, mRes; // scale resolutions per LSB for the sensors

// Pin definitions int intPin = 9; // When mounted on back pads SDA = 42, SCL = 43, and INT = 41 bool newData = false; uint8_t rawMPU9250Data[14]; uint8_t rawAK8963Data[8];

//int myLed = 13; // green led

int16_t MPU9250Data[7]; // used to read all 14 bytes at once from the MPU9250 accel/gyro int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output float magCalibration[3] = {0, 0, 0}; // Factory mag calibration and mag bias float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}, magBias[3] = {0, 0, 0}, magScale[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer int16_t tempCount; // temperature raw count output float temperature; // Stores the real internal chip temperature in degrees Celsius float SelfTest[6]; // holds results of gyro and accelerometer self test

// global constants for 9 DoF fusion and AHRS (Attitude and Heading Reference System) float GyroMeasError = PI (40.0f / 180.0f); // gyroscope measurement error in rads/s (start at 40 deg/s) float GyroMeasDrift = PI (0.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s) // There is a tradeoff in the beta parameter between accuracy and response speed. // In the original Madgwick study, beta of 0.041 (corresponding to GyroMeasError of 2.7 degrees/s) was found to give optimal accuracy. // However, with this value, the LSM9SD0 response time is about 10 seconds to a stable initial quaternion. // Subsequent changes also require a longish lag time to a stable output, not fast enough for a quadcopter or robot car! // By increasing beta (GyroMeasError) by about a factor of fifteen, the response time constant is reduced to ~2 sec // I haven't noticed any reduction in solution accuracy. This is essentially the I coefficient in a PID control sense; // the bigger the feedback coefficient, the faster the solution converges, usually at the expense of accuracy. // In any case, this is the free parameter in the Madgwick filtering and fusion scheme. float beta = sqrtf(3.0f / 4.0f) GyroMeasError; // compute beta float zeta = sqrtf(3.0f / 4.0f) GyroMeasDrift; // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value

define Kp 2.0f * 5.0f // these are the free parameters in the Mahony

filter and fusion scheme, Kp for proportional feedback, Ki for integral

define Ki 0.0f

uint32_t delt_t = 0; // used to control display output rate uint32_t count = 0, sumCount = 0; // used to control display output rate float pitch, yaw, roll; float deltat = 0.0f, sum = 0.0f; // integration interval for both filter schemes uint32_t lastUpdate = 0, firstUpdate = 0; // used to calculate integration interval uint32_t Now = 0; // used to calculate integration interval

float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method

//All measurements in inches, weights in lbs const double WB = 2.5005; //Wheelbase const double TW = 1.868; //Track width const double HH = .4455; //Hub height (aka axle height) const double RH = .642; //Raised height const double W = 97.93; //Total weight const double PW = 48.71; //Passenger weight const double RW = 51.54; //Rear weight const double RWr = 55.65; //Rear weight when raise double CGx = 0; //Center of Gravity from driver's side tire outer edge double CGy = 0; //CoG behind front axle double CGz = 0; //CoG from ground double LRTheta = 0; //Left rollover angle double RRTheta = 0; //Right rollover angle double FRTheta = 0; //Front rollover angle double ARTheta = 0; //Aft (rear) rollover angle

double MaxRoll = 0; double MaxPitch = 0;

define RAD_TO_DEG 57.295779513082320876798154814105 //180 divided by pi

include

LiquidCrystal lcd(8, 7, 5, 4, 3, 2);

const int switchPin = 6; int switchState = 0; int prevSwitchState = 0;

void setup() { Serial.begin(115200); delay(1000); Wire.begin(TWI_PINS_20_21); // set master mode Wire.setClock(400000); // I2C frequency at 400 kHz delay(1000);

// Set up the interrupt pin, it's set as active high, push-pull pinMode(intPin, INPUT); // pinMode(myLed, OUTPUT); // digitalWrite(myLed, LOW); // start with green led on (active LOW)

// Read the WHO_AM_I register, this is a good test of communication Serial.println("MPU9250 9-axis motion sensor..."); byte c = readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250 Serial.print("MPU9250 "); Serial.print("I AM "); Serial.print(c, HEX); Serial.print(" I should be "); Serial.println(0x71, HEX); delay(1000);

if (c == 0x71) // WHO_AM_I should always be 0x68 { Serial.println("MPU9250 is online...");

MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values /Serial.print("x-axis self test: acceleration trim within : "); Serial.print(SelfTest[0],1); Serial.println("% of factory value"); Serial.print("y-axis self test: acceleration trim within : "); Serial.print(SelfTest[1],1); Serial.println("% of factory value"); Serial.print("z-axis self test: acceleration trim within : "); Serial.print(SelfTest[2],1); Serial.println("% of factory value"); Serial.print("x-axis self test: gyration trim within : "); Serial.print(SelfTest[3],1); Serial.println("% of factory value"); Serial.print("y-axis self test: gyration trim within : "); Serial.print(SelfTest[4],1); Serial.println("% of factory value"); Serial.print("z-axis self test: gyration trim within : "); Serial.print(SelfTest[5],1); Serial.println("% of factory value"); delay(1000); /

// get sensor resolutions, only need to do this once getAres(); getGres(); getMres();

calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers /

accelBias[0] = 0; accelBias[1] = 0; accelBias[2] = 1; / gyroBias[0] = -4.82; gyroBias[1] = -10.18; gyroBias[2] = -.64;/ //USE THIS instead of calibrating accelerometer and gyroscope every time //Because the Jeep shaking while running will affect it. //So calibrate once while on level ground as it sits in the Jeep then store those values Serial.println("accel biases (mg)"); Serial.println(1000.accelBias[0]); Serial.println(1000.accelBias[1]); Serial.println(1000.accelBias[2]); Serial.println("gyro biases (dps)"); Serial.println(gyroBias[0]); Serial.println(gyroBias[1]); Serial.println(gyroBias[2]); delay(1000);

initMPU9250(); Serial.println("MPU9250 initialized for active data mode...."); // Initialize device for active mode read of acclerometer, gyroscope, and temperature

// Read the WHO_AM_I register of the magnetometer, this is a good test of communication byte d = readByte(AK8963_ADDRESS, WHO_AM_I_AK8963); // Read WHO_AM_I register for AK8963 Serial.print("AK8963 "); Serial.print("I AM "); Serial.print(d, HEX); Serial.print(" I should be "); Serial.println(0x48, HEX); delay(1000);

// Get magnetometer calibration from AK8963 ROM initAK8963(magCalibration); Serial.println("AK8963 initialized for active data mode...."); // Initialize device for active mode read of magnetometer

magcalMPU9250(magBias, magScale); //Serial.println("AK8963 mag biases (mG)"); Serial.println(magBias[0]); Serial.println(magBias[1]); Serial.println(magBias[2]); //Serial.println("AK8963 mag scale (mG)"); Serial.println(magScale[0]); Serial.println(magScale[1]); Serial.println(magScale[2]); delay(2000); // add delay to see results before serial spew of data

if(SerialDebug) { / Serial.println("Calibration values: "); Serial.print("X-Axis sensitivity adjustment value "); Serial.println(magCalibration[0], 2); Serial.print("Y-Axis sensitivity adjustment value "); Serial.println(magCalibration[1], 2); Serial.print("Z-Axis sensitivity adjustment value "); Serial.println(magCalibration[2], 2); / attachInterrupt(intPin, myinthandler, RISING); // define interrupt for INT pin output of MPU9250 }

} else { Serial.print("Could not connect to MPU9250: 0x"); Serial.println(c, HEX); while(1) ; // Loop forever if communication doesn't happen }

CGx = PW TW / W; CGy = RW WB / W; CGz = HH + ((RWr - RW) / W) ((sqrt((sq(WB))-(sq(RH)))WB) / RH);

Serial.print("Your x center of gravity is: "); Serial.println(CGx); Serial.print("Your y center of gravity is: "); Serial.println(CGy); Serial.print("Your z center of gravity is: "); Serial.println(CGz);

LRTheta = atan2(CGx, CGz) RAD_TO_DEG; RRTheta = atan2(TW-CGx, CGz) RAD_TO_DEG; FRTheta = atan2(CGy, CGz) RAD_TO_DEG; ARTheta = atan2(WB-CGy, CGz) RAD_TO_DEG;

lcd.begin(16, 2); lcd.setCursor(0, 0); lcd.print("Left rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(LRTheta); delay(2000); lcd.clear(); lcd.setCursor(0, 0); lcd.print("Right rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(RRTheta); delay(2000); lcd.clear(); lcd.setCursor(0, 0); lcd.print("Front rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(FRTheta); delay(2000); lcd.clear(); lcd.setCursor(0, 0); lcd.print("Rear rollover"); lcd.setCursor(0, 1); lcd.print("angle is: "); lcd.print(ARTheta); delay(2000); lcd.clear(); pinMode(switchPin, INPUT); }

void loop() { // If intPin goes high, all data registers have new data if(newData == true) { // On interrupt, read data newData = false; // reset newData flag readMPU9250Data(MPU9250Data); // INT cleared on any read // readAccelData(accelCount); // Read the x/y/z adc values

// Now we'll calculate the accleration value into actual g's ax = (float)MPU9250Data[0]aRes - accelBias[0]; // get actual g value, this depends on scale being set ay = (float)MPU9250Data[1]aRes - accelBias[1]; az = (float)MPU9250Data[2]*aRes - accelBias[2];

// readGyroData(gyroCount); // Read the x/y/z adc values

// Calculate the gyro value into actual degrees per second gx = (float)MPU9250Data[4]gRes; // get actual gyro value, this depends on scale being set gy = (float)MPU9250Data[5]gRes; gz = (float)MPU9250Data[6]*gRes;

readAK8963Data(magCount); // Read the x/y/z adc values

// Calculate the magnetometer values in milliGauss // Include factory calibration per data sheet and user environmental corrections mx = (float)magCount[0]mResmagCalibration[0] - magBias[0]; // get actual magnetometer value, this depends on scale being set my = (float)magCount[1]mResmagCalibration[1] - magBias[1]; mz = (float)magCount[2]mResmagCalibration[2] - magBias[2]; mx = magScale[0]; my = magScale[1]; mz *= magScale[2];

}

Now = micros(); deltat = ((Now - lastUpdate)/1000000.0f); // set integration time by time elapsed since last filter update lastUpdate = Now;

sum += deltat; // sum for averaging filter update rate sumCount++;

// Sensors x (y)-axis of the accelerometer/gyro is aligned with the y (x)-axis of the magnetometer;

// the magnetometer z-axis (+ down) is misaligned with z-axis (+ up) of accelerometer and gyro! // We have to make some allowance for this orientation mismatch in feeding the output to the quaternion filter. // We will assume that +y accel/gyro is North, then x accel/gyro is East. So if we want te quaternions properly aligned // we need to feed into the madgwick function Ay, Ax, -Az, Gy, Gx, -Gz, Mx, My, and Mz. But because gravity is by convention // positive down, we need to invert the accel data, so we pass -Ay, -Ax, Az, Gy, Gx, -Gz, Mx, My, and Mz into the Madgwick // function to get North along the accel +y-axis, East along the accel +x-axis, and Down along the accel -z-axis. // This orientation choice can be modified to allow any convenient (non-NED) orientation convention. // This is ok by aircraft orientation standards! // Pass gyro rate as rad/s MadgwickQuaternionUpdate(-ay, -ax, az, gyPI/180.0f, gxPI/180.0f, -gz PI/180.0f, mx, my, mz); // if(passThru)MahonyQuaternionUpdate(-ay, -ax, az, gyPI/180.0f, gxPI/180.0f, -gzPI/180.0f, mx, my, mz);

// Serial print and/or display at 1 s rate independent of data rates delt_t = millis() - count; if (delt_t > 500) { // update serial once per half-second independent of read rate

if(SerialDebug) {

Serial.print("ax = "); Serial.print((int)1000ax); Serial.print(" ay = "); Serial.print((int)1000ay); Serial.print(" az = "); Serial.print((int)1000az); Serial.println(" mg"); Serial.print("gx = "); Serial.print( gx, 2); Serial.print(" gy = "); Serial.print( gy, 2); Serial.print(" gz = "); Serial.print( gz, 2); Serial.println(" deg/s"); / Serial.print("mx = "); Serial.print( (int)mx ); Serial.print(" my = "); Serial.print( (int)my ); Serial.print(" mz = "); Serial.print( (int)mz ); Serial.println(" mG");

Serial.print("q0 = "); Serial.print(q[0]); Serial.print(" qx = "); Serial.print(q[1]); Serial.print(" qy = "); Serial.print(q[2]); Serial.print(" qz = "); Serial.println(q[3]);

*/ // tempCount = readTempData(); // Read the gyro adc values temperature = ((float) MPU9250Data[3]) / 333.87 + 21.0; // Gyro chip temperature in degrees Centigrade // Print temperature in degrees Centigrade //Serial.print("Gyro temperature is "); Serial.print(temperature, 1); Serial.println(" degrees C"); // Print T values to tenths of s degree C }

// Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation. // In this coordinate system, the positive z-axis is down toward Earth. // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination, looking down on the sensor positive yaw is counterclockwise. // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative. // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll. // These arise from the definition of the homogeneous rotation matrix constructed from quaternions. // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be // applied in the correct order which for this configuration is yaw, pitch, and then roll. // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links. //Software AHRS: yaw = atan2f(2.0f (q[1] q[2] + q[0] q[3]), q[0] q[0] + q[1] * q[1]

• q[2] q[2] - q[3] q[3]); pitch = -asinf(2.0f (q[1] q[3] - q[0] q[2])); roll = atan2f(2.0f (q[0] q[1] + q[2] q[3]), q[0] q[0] - q[1] q[1] - q[2] q[2] + q[3] q[3]); pitch = 180.0f / PI; yaw = 180.0f / PI; yaw += 0.13f; // .13 is the mag dec for Missouri Example: Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04 so you would use 13.8 if(yaw < 0) yaw += 360.0f; // Ensure yaw stays between 0 and 360 roll *= 180.0f / PI;

if(SerialDebug) { Serial.print("Pitch & Roll: "); //Serial.print(yaw, 2); //Serial.print(", "); Serial.print(pitch, 2); Serial.print(", "); Serial.println(roll, 2);

// Serial.print("rate = "); Serial.print((float)sumCount/sum, 2); Serial.println(" Hz");

if(abs(pitch) > MaxPitch && millis() > 100000) { MaxPitch = abs(pitch); } else if (abs(roll) > MaxRoll && millis() > 100000) { MaxRoll = abs(roll); } else {} Serial.println("Maximum Pitch & Roll"); Serial.print(MaxPitch, 2); Serial.print(","); Serial.println(MaxRoll, 2); }

count = millis(); sumCount = 0; sum = 0; }

lcd.setCursor(0, 0); lcd.print("Pitch: "); lcd.print(pitch); lcd.setCursor(0, 1); lcd.print("Roll: "); lcd.print(roll); delay(100); switchState = digitalRead(switchPin); if (switchState != prevSwitchState) { if (switchState == LOW) { lcd.clear(); lcd.setCursor(0,0); lcd.print("Max Pitch:"); lcd.print(MaxPitch); lcd.setCursor(0,1); lcd.print("Max Roll:"); lcd.print(MaxRoll); delay(5000); } } prevSwitchState = switchState; }

//=================================================================================================================== //====== Set of useful function to access acceleration. gyroscope, magnetometer, and temperature data

//===================================================================================================================

void myinthandler() { uint8_t subAddress = ACCEL_XOUT_H;

Wire.transfer(MPU9250_ADDRESS, &subAddress, 1, &rawMPU9250Data[0], 14, true, mywirehandler1); }

void mywirehandler1(uint8_t status) { uint8_t subAddress = AK8963_ST1;

Wire.transfer(AK8963_ADDRESS, &subAddress, 1, &rawAK8963Data[0], 8, true, mywirehandler2); }

void mywirehandler2(uint8_t status) { newData = true; }

void getMres() { switch (Mscale) { // Possible magnetometer scales (and their register bit settings) are: // 14 bit resolution (0) and 16 bit resolution (1) case MFS_14BITS: mRes = 10.4912./8190.; // Proper scale to return milliGauss break; case MFS_16BITS: mRes = 10.4912./32760.0; // Proper scale to return milliGauss break; } }

void getGres() { switch (Gscale) { // Possible gyro scales (and their register bit settings) are: // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11). // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: case GFS_250DPS: gRes = 250.0/32768.0; break; case GFS_500DPS: gRes = 500.0/32768.0; break; case GFS_1000DPS: gRes = 1000.0/32768.0; break; case GFS_2000DPS: gRes = 2000.0/32768.0; break; } }

void getAres() { switch (Ascale) { // Possible accelerometer scales (and their register bit settings) are: // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11). // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value: case AFS_2G: aRes = 2.0/32768.0; break; case AFS_4G: aRes = 4.0/32768.0; break; case AFS_8G: aRes = 8.0/32768.0; break; case AFS_16G: aRes = 16.0/32768.0; break; } }

void readMPU9250Data(int16_t * destination) { destination[0] = ((int16_t)rawMPU9250Data[0] << 8) | rawMPU9250Data[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawMPU9250Data[2] << 8) | rawMPU9250Data[3] ; destination[2] = ((int16_t)rawMPU9250Data[4] << 8) | rawMPU9250Data[5] ; destination[3] = ((int16_t)rawMPU9250Data[6] << 8) | rawMPU9250Data[7] ; destination[4] = ((int16_t)rawMPU9250Data[8] << 8) | rawMPU9250Data[9] ; destination[5] = ((int16_t)rawMPU9250Data[10] << 8) | rawMPU9250Data[11] ; destination[6] = ((int16_t)rawMPU9250Data[12] << 8) | rawMPU9250Data[13] ;

}

void readAK8963Data(int16_t * destination) { if(rawAK8963Data[0] & 0x01) { // wait for magnetometer data ready bit to be set uint8_t c = rawAK8963Data[7]; // End data read by reading ST2 register if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data destination[0] = ((int16_t)rawAK8963Data[2] << 8) | rawAK8963Data[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawAK8963Data[4] << 8) | rawAK8963Data[3] ; // Data stored as little Endian destination[2] = ((int16_t)rawAK8963Data[6] << 8) | rawAK8963Data[5] ; } } }

void readAccelData(int16_t * destination) { uint8_t rawData[6]; // x/y/z accel register data stored here readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array destination[0] = ((int16_t)rawData[0] << 8) | rawData[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawData[2] << 8) | rawData[3] ; destination[2] = ((int16_t)rawData[4] << 8) | rawData[5] ; }

void readGyroData(int16_t * destination) { uint8_t rawData[6]; // x/y/z gyro register data stored here readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array destination[0] = ((int16_t)rawData[0] << 8) | rawData[1] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawData[2] << 8) | rawData[3] ; destination[2] = ((int16_t)rawData[4] << 8) | rawData[5] ; }

void readMagData(int16_t * destination) { uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array uint8_t c = rawData[6]; // End data read by reading ST2 register if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data destination[0] = ((int16_t)rawData[1] << 8) | rawData[0] ; // Turn the MSB and LSB into a signed 16-bit value destination[1] = ((int16_t)rawData[3] << 8) | rawData[2] ; // Data stored as little Endian destination[2] = ((int16_t)rawData[5] << 8) | rawData[4] ; } } }

int16_t readTempData() { uint8_t rawData[2]; // x/y/z gyro register data stored here readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array return ((int16_t)rawData[0] << 8) | rawData[1] ; // Turn the MSB and LSB into a 16-bit value }

void initAK8963(float * destination) { // First extract the factory calibration for each magnetometer axis uint8_t rawData[3]; // x/y/z gyro calibration data stored here writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer delay(10); writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode delay(10); readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values destination[0] = (float)(rawData[0] - 128)/256. + 1.; // Return x-axis sensitivity adjustment values, etc. destination[1] = (float)(rawData[1] - 128)/256. + 1.; destination[2] = (float)(rawData[2] - 128)/256. + 1.; writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer delay(10); // Configure the magnetometer for continuous read and highest resolution // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register, // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR delay(10); }

void initMPU9250() { // wake up device writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors delay(100); // Wait for all registers to reset

// get stable time source writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Auto select clock source to be PLL gyroscope reference if ready else delay(200);

// Configure Gyro and Thermometer // Disable FSYNC and set thermometer and gyro bandwidth to 41 and 42 Hz, respectively; // minimum delay time for this setting is 5.9 ms, which means sensor fusion update rates cannot // be higher than 1 / 0.0059 = 170 Hz // DLPF_CFG = bits 2:0 = 011; this limits the sample rate to 1000 Hz for both // With the MPU9250, it is possible to get gyro sample rates of 32 kHz (!), 8 kHz, or 1 kHz writeByte(MPU9250_ADDRESS, CONFIG, 0x03);

// Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV) writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Use a 1000 Hz rate; a rate consistent with the filter update rate // determined inset in CONFIG above

// Set gyroscope full scale range // Range selects FS_SEL and GFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3 uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG); // get current GYRO_CONFIG register value // c = c & ~0xE0; // Clear self-test bits [7:5] c = c & ~0x03; // Clear Fchoice bits [1:0] c = c & ~0x18; // Clear GS bits [4:3] c = c | Gscale << 3; // Set full scale range for the gyro // c =| 0x00; // Set Fchoice for the gyro to 11 by writing its inverse to bits 1:0 of GYRO_CONFIG writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c ); // Write new GYRO_CONFIG value to register

// Set accelerometer full-scale range configuration c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG); // get current ACCEL_CONFIG register value // c = c & ~0xE0; // Clear self-test bits [7:5] c = c & ~0x18; // Clear AFS bits [4:3] c = c | Ascale << 3; // Set full scale range for the accelerometer writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c); // Write new ACCEL_CONFIG register value

// Set accelerometer sample rate configuration // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2); // get current ACCEL_CONFIG2 register value c = c & ~0x0F; // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0]) c = c | 0x03; // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c); // Write new ACCEL_CONFIG2 register value

// The accelerometer, gyro, and thermometer are set to 1 kHz sample rates

// Configure Interrupts and Bypass Enable // Set interrupt pin active high, push-pull, hold interrupt pin level HIGH until interrupt cleared, // clear on read of INT_STATUS, and enable I2C_BYPASS_EN so additional chips // can join the I2C bus and all can be controlled by the Arduino as master // writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22); writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x12); // INT is 50 microsecond pulse and any read to clear writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt delay(100); }

void magcalMPU9250(float dest1, float dest2) { uint16_t ii = 0, sample_count = 0; int32_t mag_bias[3] = {0, 0, 0}, mag_scale[3] = {0, 0, 0}; int16_t mag_max[3] = {-32767, -32767, -32767}, mag_min[3] = {32767, 32767, 32767}, mag_temp[3] = {0, 0, 0};

//Serial.println("Mag Calibration: Wave device in a figure eight until done!"); //delay(4000); //COMMENTED THE ABOVE 2 LINES OUT BECAUSE NO NEED FOR MAG IF NOT USING YAW

// shoot for ~fifteen seconds of mag data if(Mmode == 0x02) sample_count = 128; // at 8 Hz ODR, new mag data is available every 125 ms if(Mmode == 0x06) sample_count = 1500; // at 100 Hz ODR, new mag data is available every 10 ms for(ii = 0; ii < sample_count; ii++) { readMagData(mag_temp); // Read the mag data for (int jj = 0; jj < 3; jj++) { if(mag_temp[jj] > mag_max[jj]) mag_max[jj] = mag_temp[jj]; if(mag_temp[jj] < mag_min[jj]) mag_min[jj] = mag_temp[jj]; } if(Mmode == 0x02) delay(135); // at 8 Hz ODR, new mag data is available every 125 ms if(Mmode == 0x06) delay(12); // at 100 Hz ODR, new mag data is available every 10 ms }

// Serial.println("mag x min/max:"); Serial.println(mag_max[0]); Serial.println(mag_min[0]); // Serial.println("mag y min/max:"); Serial.println(mag_max[1]); Serial.println(mag_min[1]); // Serial.println("mag z min/max:"); Serial.println(mag_max[2]); Serial.println(mag_min[2]);

// Get hard iron correction mag_bias[0] = (mag_max[0] + mag_min[0])/2; // get average x mag bias in counts mag_bias[1] = (mag_max[1] + mag_min[1])/2; // get average y mag bias in counts mag_bias[2] = (mag_max[2] + mag_min[2])/2; // get average z mag bias in counts

dest1[0] = (float) mag_bias[0]mResmagCalibration[0]; // save mag biases in G for main program dest1[1] = (float) mag_bias[1]mResmagCalibration[1]; dest1[2] = (float) mag_bias[2]mResmagCalibration[2];

// Get soft iron correction estimate mag_scale[0] = (mag_max[0] - mag_min[0])/2; // get average x axis max chord length in counts mag_scale[1] = (mag_max[1] - mag_min[1])/2; // get average y axis max chord length in counts mag_scale[2] = (mag_max[2] - mag_min[2])/2; // get average z axis max chord length in counts

float avg_rad = mag_scale[0] + mag_scale[1] + mag_scale[2]; avg_rad /= 3.0;

dest2[0] = avg_rad/((float)mag_scale[0]); dest2[1] = avg_rad/((float)mag_scale[1]); dest2[2] = avg_rad/((float)mag_scale[2]);

//Serial.println("Mag Calibration done!"); }

// Function which accumulates gyro and accelerometer data after device initialization. It calculates the average // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers. void calibrateMPU9250(float dest1, float dest2) { uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data uint16_t ii, packet_count, fifo_count; int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0};

// reset device writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device delay(100);

// get stable time source; Auto select clock source to be PLL gyroscope reference if ready // else use the internal oscillator, bits 2:0 = 001 writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00); delay(200);

// Configure device for bias calculation writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP delay(15);

// Configure MPU6050 gyro and accelerometer for bias calculation writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity

uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec uint16_t accelsensitivity = 16384; // = 16384 LSB/g

// Configure FIFO to capture accelerometer and gyro data for bias calculation

writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9150) delay(40); // accumulate 40 samples in 40 milliseconds = 480 bytes

// At end of sample accumulation, turn off FIFO sensor read writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO readBytes(MPU9250_ADDRESS, FIFO_COUNTH, 2, &data[0]); // read FIFO sample count fifo_count = ((uint16_t)data[0] << 8) | data[1]; packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging

for (ii = 0; ii < packet_count; ii++) { int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0}; readBytes(MPU9250_ADDRESS, FIFO_R_W, 12, &data[0]); // read data for averaging accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ; accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ; gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ; gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ; gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ;

accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases accel_bias[1] += (int32_t) accel_temp[1]; accel_bias[2] += (int32_t) accel_temp[2]; gyro_bias[0] += (int32_t) gyro_temp[0]; gyro_bias[1] += (int32_t) gyro_temp[1]; gyro_bias[2] += (int32_t) gyro_temp[2];

} accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases accel_bias[1] /= (int32_t) packet_count; accel_bias[2] /= (int32_t) packet_count; gyro_bias[0] /= (int32_t) packet_count; gyro_bias[1] /= (int32_t) packet_count; gyro_bias[2] /= (int32_t) packet_count;

if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation else {accel_bias[2] += (int32_t) accelsensitivity;}

// Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup data[0] = (-gyro_bias[0]/4 >> 8) & 0xFF; // Divide by 4 to get 32.9 LSB per deg/s to conform to expected bias input format data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF; data[3] = (-gyro_bias[1]/4) & 0xFF; data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF; data[5] = (-gyro_bias[2]/4) & 0xFF;

// Push gyro biases to hardware registers writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]); writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]); writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]); writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]); writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]); writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, data[5]);

// Output scaled gyro biases for display in the main program dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity; dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity;

// Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that // the accelerometer biases calculated above must be divided by 8.

int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases readBytes(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values accel_bias_reg[0] = (int32_t) (((int16_t)data[0] << 8) | data[1]); readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]); accel_bias_reg[1] = (int32_t) (((int16_t)data[0] << 8) | data[1]); readBytes(MPU9250_ADDRESS, ZA_OFFSET_H, 2, &data[0]); accel_bias_reg[2] = (int32_t) (((int16_t)data[0] << 8) | data[1]);

uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis

for(ii = 0; ii < 3; ii++) { if((accel_bias_reg[ii] & mask)) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit }

// Construct total accelerometer bias, including calculated average accelerometer bias from above accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale) accel_bias_reg[1] -= (accel_bias[1]/8); accel_bias_reg[2] -= (accel_bias[2]/8);

data[0] = (accel_bias_reg[0] >> 8) & 0xFF; data[1] = (accel_bias_reg[0]) & 0xFF; data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[2] = (accel_bias_reg[1] >> 8) & 0xFF; data[3] = (accel_bias_reg[1]) & 0xFF; data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[4] = (accel_bias_reg[2] >> 8) & 0xFF; data[5] = (accel_bias_reg[2]) & 0xFF; data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers

// Apparently this is not working for the acceleration biases in the MPU-9250 // Are we handling the temperature correction bit properly? // Push accelerometer biases to hardware registers // writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]); // writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]); // writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]); // writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]); // writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]); // writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, data[5]);

// Output scaled accelerometer biases for display in the main program dest2[0] = (float)accel_bias[0]/(float)accelsensitivity; dest2[1] = (float)accel_bias[1]/(float)accelsensitivity; dest2[2] = (float)accel_bias[2]/(float)accelsensitivity; }

// Accelerometer and gyroscope self test; check calibration wrt factory settings void MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass { uint8_t rawData[6] = {0, 0, 0, 0, 0, 0}; uint8_t selfTest[6]; int32_t gAvg[3] = {0}, aAvg[3] = {0}, aSTAvg[3] = {0}, gSTAvg[3] = {0}; float factoryTrim[6]; uint8_t FS = 0;

writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz writeByte(MPU9250_ADDRESS, GYRO_CONFIG, FS<<3); // Set full scale range for the gyro to 250 dps writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, FS<<3); // Set full scale range for the accelerometer to 2 g

for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer

readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;

readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array

gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; }

for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings aAvg[ii] /= 200; gAvg[ii] /= 200; }

// Configure the accelerometer for self-test writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s delay(25); // Delay a while to let the device stabilize

for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer

readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;

readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array

gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ; gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ; }

for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings aSTAvg[ii] /= 200; gSTAvg[ii] /= 200; }

// Configure the gyro and accelerometer for normal operation writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00); writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); delay(25); // Delay a while to let the device stabilize

// Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results

// Retrieve factory self-test value from self-test code reads factoryTrim[0] = (float)(2620/1<<FS) (pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation factoryTrim[1] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation factoryTrim[2] = (float)(2620/1<<FS) (pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation factoryTrim[3] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation factoryTrim[4] = (float)(2620/1<<FS) (pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation factoryTrim[5] = (float)(2620/1<<FS)(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation

// Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response // To get percent, must multiply by 100 for (int i = 0; i < 3; i++) { destination[i] = 100.0((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i] - 100.; // Report percent differences destination[i+3] = 100.0((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3] - 100.; // Report percent differences }

}

// I2C read/write functions for the MPU9250 sensors

void writeByte(uint8_t address, uint8_t subAddress, uint8_t data) {
uint8_t temp[2];
temp[0] = subAddress;
temp[1] = data;
Wire.transfer(address, &temp[0], 2, NULL, 0);
}

uint8_t readByte(uint8_t address, uint8_t subAddress) {
uint8_t temp[1];
Wire.transfer(address, &subAddress, 1, &temp[0], 1);
return temp[0];
}

void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) {
Wire.transfer(address, &subAddress, 1, dest, count);
}

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[beaumr2]

I get that it's a rats nest but trust me that's not the problem

Using this board, same wiring, it works fine. Only problem is one axis of the accelerometer is junk as we talked about a few days ago https://smile.amazon.com/gp/product/B01I1J0Z7Y/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

And using this board I get the error that it can't connect https://www.tindie.com/products/onehorse/ultimate-sensor-fusion-solution-mpu9250/ I know the wires are making good connections. Tested them with voltmeter and have run the code over and over doing my best to make sure there's contact (don't want to solder until I confirm it works)

[beaumr2]

I shouldn't need to change any code switching from one board to the other right?

[kriswiner]

Then at least use dupont jumpers with j-hooks for the connections. I sometimes just use Dupont jumpers too to test function but then I dont seem to have these kinds of problems either.

My recommendation is to solder machine pin headers onto the sensor board and Dragonfly, use 24 - 26 gauge wire to connect on a breadboard and then test. Guaranteed to work.

On Sun, Aug 30, 2020 at 6:35 PM beaumr2 notifications@github.com wrote:

I get that it's a rats nest but trust me that's not the problem

Using this board, same wiring, it works fine. Only problem is one axis of the accelerometer is junk as we talked about a few days ago

https://smile.amazon.com/gp/product/B01I1J0Z7Y/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

And using this board I get the error that it can't connect

https://www.tindie.com/products/onehorse/ultimate-sensor-fusion-solution-mpu9250/ I know the wires are making good connections. Tested them with voltmeter and have run the code over and over doing my best to make sure there's contact (don't want to solder until I confirm it works)

— You are receiving this because you commented. Reply to this email directly, view it on GitHub https://github.com/kriswiner/MPU9250/issues/421#issuecomment-683507232, or unsubscribe https://github.com/notifications/unsubscribe-auth/ABTDLKQBWDW2KJGKTHECEVDSDL45HANCNFSM4N4V4CIQ .

[kriswiner]

Why should you?

I suspect that your connections are not good enough.

On Sun, Aug 30, 2020 at 6:38 PM beaumr2 notifications@github.com wrote:

I shouldn't need to change any code switching from one board to the other right?

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[beaumr2]

These pictures enough to convince you? Black = SDA/Pin 20, Yellow = SCL/Pin 21, Green = 3V3/3V3, Red = GND/GND

I was mistaken about Pin 29->SCL and 28-> SDA. They're actually pins 21 and 20, respectively. I said 29/28 because they're right under the pin labeled 30

It's definitely not the wiring. I've rewired the old MPU9250 twice and it immediately works. With the new MPU9250 no matter how much i try to ensure the wires are making contact it never works

[beaumr2]

Also my bad, didn't connect the INT pin there to pin 9. Same result with it connected

[kriswiner]

Don't know what to tell you. I test each of the MPU9250 boards before I send them out. It is guaranteed to work unless it is not connected correctly (which I suspect) or you are foo-barring the sketch.

If you can't read the WHOAMI from the MPU9250 then it is not connected properly.

On Mon, Aug 31, 2020 at 2:36 PM beaumr2 notifications@github.com wrote:

Also my bad, didn't connect the INT pin there to pin 9. Same result with it connected

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[beaumr2]

Here's the new MPU9250. I know it's a pain to look between the wires but I promise they're all wired correctly and making contact. About to post the other pictures showing the same wiring for the old MPU9250

[beaumr2]

![Uploading IMG_9634.JPG…]() ![Uploading IMG_0450.JPG…]()

[beaumr2]

[kriswiner]

Now that I can see your board I see that it is not an MPU9250 breakout board but an EM7180 coprocessor managing an MPU9250 and BMP280, right?

You should see the EM7180 at 0x28.

Maybe you should try the appropriate https://github.com/gregtomasch/EM7180_SENtral_Calibration sketch?

On Tue, Sep 1, 2020 at 1:44 PM beaumr2 notifications@github.com wrote:

[image: IMG_0450] https://user-images.githubusercontent.com/29678274/91904020-d35c8a80-ec69-11ea-85b8-a460d7963c0e.JPG [image: IMG_9634] https://user-images.githubusercontent.com/29678274/91904026-d6577b00-ec69-11ea-9a25-3c1a8dd6c90f.JPG

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[beaumr2]

Yep that was the issue. Working now, just need to tackle the calibration part of it

[beaumr2]

Thanks so much for all your help!!! Got my project complete, only 3 months later :)

Here's a video if you're curious. Anyway, thanks so much again. You've been great at dealing with my stupidity