pxt-microbit
Version:
micro:bit target for Microsoft MakeCode (PXT)
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Markdown
# Device
### ~ hint
#### Looking to buy a micro:bit?
See the [list of official products](https://microbit.org/buy/).
### ~
All the bits and pieces that make up the BBC micro:bit

### ~ hint
#### The current version of micro:bit is v2
The version of @boardname@ is now currently at **v2**. See the what's new in MakeCode for programming the [@boardname@ v2](/device/v2).
### ~
## LED Screen and Status LED
The red lights are [LEDs](/device/screen) (light emitting diodes) and form a 5 x 5 LED Screen.
They can be set to on/off and the brightness can be controlled.
The yellow light on the back of the micro:bit is the status LED.
It flashes yellow when the system wants to tell the user that something has happened.
See how the @boardname@ shows numbers, text, and displays images by watching this video about LEDs:
https://www.youtube.com/watch?v=qqBmvHD5bCw
## Buttons
Buttons **A** and **B** are a form of input. When you press a button, it completes an electrical circuit.
The micro:bit can detect either of its two buttons being pressed/released and be programmed
to act on these events.
Button **R** on the back of the micro:bit is a system button. It has different uses.
When you have downloaded and run your code onto your micro:bit, press Button **R** to restart and run your program from the beginning.
Find out how buttons provide input to the @boardname@ in this video:
https://www.youtube.com/watch?v=t_Qujjd_38o
## Touch
Pins **0**, **1**, **2**, and the board **logo** can work as touch buttons when they are programmed for input.
## USB connection
When you plug in your micro:bit via [USB](/device/usb), it should appear as a ``MICROBIT`` drive.
If you accidentally hold down the reset button as you’re plugging in your micro:bit,
the micro:bit will appear as a ``MAINTENANCE`` drive instead of ``MICROBIT``. This is known as maintenance mode.
To continue programming your micro:bit YOU MUST unplug your USB and reconnect it. Check that the drive now shows as ``MICROBIT``.
### ~ hint
#### Open the version file
Use with caution!
If you click on the drive while it shows the ``MAINTENANCE`` label,
you can see which version of firmware you have running on your micro:bit.
Firmware on your micro:bit should be up-to-date already.
You can find the version of firmware in the 'version.txt' file on the micro:bit. See the @boardname@ **[firmware](https://microbit.org/guide/firmware/)** page for more about checking your board's firmware version.
### ~
## Compass
The compass can detect magnetic fields such as the Earth’s magnetic field.
As the micro:bit has this compass, it is possible to detect the direction it is moving in.
The micro:bit can detect where it is facing and movement in degrees.
This data can be used by the micro:bit in a program or be sent to another device.
## Accelerometer
There is an accelerometer on your micro:bit which detects changes in the micro:bit’s speed.
It converts analogue information into digital form that can be used in micro:bit programs.
Output is in milli-g. The device will also detect a small number of standard actions e.g. shake, tilt and free-fall.
Watch this video to learn how the accelerometer works:
https://www.youtube.com/watch?v=byngcwjO51U
## Pins
The [pins](/device/pins) can be a form of electrical input or output.
There are labels for the input/output pins **0**, **1**, **2**, which you can attach external sensors to such as thermometers or moisture detectors.
## Microphone
Using the microphone, your programs can detect sounds that are present. You can check for loud or quiet sounds and find out what their sound level is.
## Light level
The screen can also be used a light level sensor (it's a really cool trick).
Learn more about how light level is detected in this light sensor video:
https://www.youtube.com/watch?v=TKhCr-dQMBY
## Temperature
Temperature is measured on the @boardname@ by detecting how hot its physical CPU material is. Since it operates nearly as cool as the air around it, the temperature it measures for itself is a good approximation for the ambient temperature (the temperature near and around it).
See how the @boardname@ can detect hot or cold in this temperature sensing video:
https://www.youtube.com/watch?v=_T4N8O9xsMA
## Runtime
The micro:bit embodies many fundamental concepts in computer science. To learn more, read [the micro:bit - a reactive system](/device/reactive).
Sometimes, your micro:bit may display an error code. For more information, see:
* [the error codes](/device/error-codes)
## How do I connect the micro:bit to my computer?
Your micro:bit can be connected to your computer via a micro USB cable.
Data can be sent and received between the micro:bit and the computer so programs
can be downloaded from Windows, Macs and Chromebooks onto the micro:bit via this USB data connection.
[Click here to read more information on how to run scripts on your micro:bit](/device/usb),
and [click here to read more about the error messages you might get](/device/error-codes).
## Powering your micro:bit
When your micro:bit is connected to your computer with the micro USB, it doesn’t need another power source.
When your micro:bit isn’t connected to your computer, tablet or mobile, you will need 2 x AAA 1.5 V batteries to power it.
The pins labelled **3V** and **GND** are the power supply pins.
You can attach an external device such as a motor to these and power it using the battery or USB.
## Serial Communication
The micro:bit can send and receive data via [serial communication](/device/serial). The serial data can be transferred via [USB](/reference/serial/redirect-to-usb), BLE or [redirected to pins](/reference/serial/redirect) on the edge connector.
## Bluetooth Low Energy (BLE) Antenna
You will see the label BLE ANTENNA on the back of your micro:bit. It is for a messaging service,
so that devices can talk to each other. The micro:bit is a peripheral
device which can talk to a central device like a smart phone or tablet that has Bluetooth Low Energy (BLE).
The micro:bit can send signals and receive signals from a central device so another BLE device can
control the micro:bit or the micro:bit can control another BLE device.
## Technical Information
The micro:bit has been designed to be a bare-board micro controller for use by children aged 11-12.
More information is available at the [Microbit Foundation web site](https://microbit.org/guide/).