Using the Micro:bit onboard accelerometer a Micropython example

by shedboy71 25th January 2019

The micro:bit has an accelerometer on board, you can see this in the picture below of the layout of the board

microbit

For those that are interested it is actually a MMA8653FC . Here is some basic info from the NXP website

The NXP^® MMA8653FC 10-bit accelerometer has industry leading performance in a small DFN package. Packed with embedded functions that include:

Flexible user-programmable options and two configurable interrupt pins
Overall power savings through inertial wake-up interrupt signals that monitor events and remain in a low-power mode during periods of inactivity

Features

Low-profile 2 x 2 x 1.0 mm DFN package
High sensitivity: 1 mg per LSB
Low noise: 150 micro g per root Hertz (independent of resolution)
Low-power mode: 7 micro amps
Interrupt and IIC interface supply: 1.62 to 3.6 V
Supply voltage : 1.95 to 3.6 V
Output data rate: 1.5 to 800 Hz

The datasheet is available from https://www.nxp.com/docs/en/data-sheet/MMA8653FC.pdf

Of course you do not really need to worry about the technical details unless like me you like looking at datasheets

When you flash the program, you should see a reading of the accelerometer x axis being printed at the bottom of the Mu application. You can move the Micro:bit around and the values should change

Code

[codesyntax lang=”python”]

from microbit import *

while True:
    x = accelerometer.get_x()
    print(x)
    sleep(1000)

[/codesyntax]

You can also use the get_y and get_z() methods to find out the readings on the other axes. here is an example showing this

[codesyntax lang=”python”]

from microbit import *
while True:
x = accelerometer.get_x()
y = accelerometer.get_y()
z = accelerometer.get_z()
print ("x: " + str(x) + " y: " + str(y) + " z: "+ str(z))
sleep(1000)

[/codesyntax]