Hardware

BBC micro:bit Hardware Specification

16 MHz 32-bit ARM Cortex-M0 microcontroller, 256 KB flash memory, 16 KB static ram, 2.4 GHz Bluetooth low energy wireless networking. The ARM core has the capability to switch between 16 MHz or 32.768 kHz.

USB

Bluetooth

2 buttons A and B + a Reset button underneath

micro:bit pins

3-axis accelerometer sensor via I²C-bus NXP MMA8652

3-axis magnetometer sensor via I²C-bus (to act as a compass and metal detector) NXP MAG3110

Edge connector

Power

power supplied from the battery connector and USB connector are both protected by diodes.

The USB input voltage is regulated down to 3.3Volts

Minimum supply voltage via the pins is 1.71Volts but MUST NOT exceed 3.6Volts.

NOTE the pin voltage input is not protected in any way

Input Output (I/O) Pins

pins have alternate assigned functions for use by the micro:bit, many of these can be disabled in software to gain more general purpose IO pins.

10 Mohm Pull-up resistors are included on pins P0 P1 and P2 for use in touch sensing mode, where they provide a weak pull-up to the supply providing a default high input and the user touching the GND pad pulls the pin down towards 0V, providing a low input.

Communication Interfaces

Radio

I2C