MPU 6050

Description

The MPU-6050 is a sensor that combines a 3-axis gyroscope and 3-axis accelerometer. Here it is used as the GY-521 module that can be directly connected to the ESP32/ES8266. The module is connected via the I2C bus.

more details for advanced users:

• https://invensense.tdk.com/wp-content/uploads/2015/02/MPU-6000-Datasheet1.pdf (Datasheet)

How to connect it electrically

The MPU 6050 is connected to the I2C bus. This is the same as where the display is connected.

• Pin15 is SCL (OLED_SCL)
• Pin4 is SDA (OLED_SDA)

Required Module and Files

• We use two modules:
  • imu.py
  • vector3d.py
• this is downloaded from https://github.com/micropython-IMU/micropython-mpu9x50
• the original files are at
  • https://github.com/micropython-IMU/micropython-mpu9x50/blob/master/imu.py
  • https://github.com/micropython-IMU/micropython-mpu9x50/blob/master/vector3d.py

There are other libraries available, e.g. https://github.com/adamjezek98/MPU6050-ESP8266-MicroPython

How to control it in MicroPython

from machine import I2C, Pin 
from imu import MPU6050

# Pins according the schematic https://heltec.org/project/wifi-kit-32/
i2c = I2C(-1, scl=Pin(15), sda=Pin(4))

imu = MPU6050(i2c)

# print all values
print(imu.accel.xyz)
print(imu.gyro.xyz)
print(imu.temperature)

#print a single value, e.g. x value of acceleration
print(imu.accel.x)

Program: Showing all Values on the Display

This shows all values of the MPU6050 on the OLED Display

from machine import I2C, Pin 
import ssd1306
from imu import MPU6050
from time import sleep

# ESP32 reset pin for display must be 1 - this is pin16 
# should be done in ssd1306.py - if not uncommend the next 2 lines
#pin16 = Pin(16, Pin.OUT)
#pin16.value(1)


# Pins according the schematic https://heltec.org/project/wifi-kit-32/
i2c = I2C(-1, scl=Pin(15), sda=Pin(4))

#display size
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)

#link IMU to the i2C bus
imu = MPU6050(i2c)

while True:
  # read in analog value in v
  x = imu.accel.x
  y = imu.accel.y
  z = imu.accel.z
  xg = imu.gyro.x
  yg = imu.gyro.y
  zg = imu.gyro.z
  t = imu.temperature
  
  # print to serial line
  print("x:", x, "y: ", y, "z:", z)
  # empty display
  oled.fill(0)
  oled.show()
  # write v converted to a string onto the display at (0,0)
  oled.text("x:"+str(x), 0, 0)
  oled.text("y:"+str(y), 0, 9)
  oled.text("z:"+str(z), 0, 18)
  oled.text("xg:"+str(xg), 0, 27)
  oled.text("yg:"+str(yg), 0, 36)
  oled.text("zg:"+str(zg), 0, 45)
  oled.text("t:"+str(t), 0, 54)
  oled.show()
  sleep(0.3)