GrayBlue

This is M5Stack Gray firmware to notify 9DOF motion sensor(MPU-9250) data by Bluetooth Low Enagy.

Therefore .

Demo

Applied the notified quaternion to the virtual object with Unity.

Description

IMU

MPU-9250 provide these data.

• acceleration (xyz) [mg]
• gyro (xyz) [deg/s]
• magnetic force (xyz) [mG]
• quaternion (wxyz) []

Quaternion is calculated from acc and gyro by DMP of MPU-9250. These 13(3+3+3+4) data are notified by BLE.

Front 3 buttons

Press or release 3 buttons on front is also notified by BLE.

BLE

Above data are notified by BLE Gatt.

9-DOF data profile

• Service UUID: c87ace96-3523-11e9-b210-d663bd873d93
• Characteristics
  • UUID: c87ad148-3523-11e9-b210-d663bd873d93
  • type: 52 byte binary array. (13 float value)
  • format:
    • accX [0:3]
    • accY [4:7]
    • accZ [8:11]
    • gyroX [12:15]
    • gyroY [16:19]
    • gyroZ [20:23]
    • magX [24:27]
    • magY [28:31]
    • magZ [32:35]
    • quatW [36:39]
    • quatX [40:43]
    • quatY [44:47]
    • quatZ [48:51]

Button event profile

• Service UUID: de4c3b20-26ea-11e9-ab14-d663bd873d93
• Characteristics
  • UUID: de4c4016-26ea-11e9-ab14-d663bd873d93
  • type: 4 byte value
  • format:
    • isPressed [0] (pressed=1/release=0)
    • buttonType [1] (left='A'/center='B'/right='C')
    • pressTime [2:3] (milliSeconds. On button press, value=0.)

Install

This project use PlatformIO.

If you try to build and write to your M5Stack Gray, you need to install PlatformIO environment on your PC.

Library

• M5Stack
  • https://github.com/m5stack/M5Stack
  • LICENSE
• SparkFun_MPU-9250-DMP_Arduino_Library
  • https://github.com/sparkfun/SparkFun_MPU-9250-DMP_Arduino_Library
  • LICENSE

Licence

MIT

Author

@naninunenoy