Error Codes

micro:bit error codes and what they mean

A micro:bit with an error.

Your micro:bit may encounter a situation that prevents it from running your code. When this happens, a frowny face will appear on your micro:bit screen followed by an error number.

Whenever this happens, you should:

  • Press the reset button on the back of the device to restart your program.
  • Flash the script to your micro:bit again.

If the problem persists please report the issue to us.

Submit a support ticket

Error Numbers

Here is a list of error numbers and what they mean:

Error number     What this means   
10 The micro:bit's I2C bus is not working. The device might be physically damaged.
20 There is no free memory on the micro:bit. Your program might be too complex or contain a lot of large variables. Try reducing your code by making functions out of large sections.
30 Corruption detected in the micro:bit heap space (memory allocated usually for the storage of variables). Try flashing a different .hex file to your device
40 Your micro:bit can't execute your script properly.Flash a different .hex file to it, then try flashing and running your previous script again.
42 Your micro:bit can't execute your script properly.Flash a different .hex file to it, then try flashing and running your previous script again.
43 An error occurred with the micro:bit's radio component.
50 An error occurred with the micro:bit's accelerometer component.
51 An error occurred with the micro:bit's magnetometer component.
98 A MakeCode editor error that occurs when there is a problem with the Control blocks.

Check out our Knowledgebase article for additional information about micro:bit errors.

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