Parts of the BBC micro:bit#
The micro:bit has several components. Some of these components are programmable and can be directly controlled with MakeCode blocks. Other components are non-programmable, cannot be controlled in MakeCode, and work independently.
The programmable components are as follows:
The 5×5 LED Matrix Display
The General-Purpose Input/Output Pins (GPIO)
The A and B Buttons
The Sound Sensor/Microphone
The Buzzer/Speaker
The Accelerometer/Compass
The Temperature Sensor
The Captive Touch Buttons
The non-programmable components are as follows:
The Processor
The Bluetooth Antenna
The Micro USB Connector
The Power Connector
The Reset Button
These components are explained in greater detail below:
Programmable Components#
As mentioned above, the micro:bit has many programmable components that can be directly controlled using MakeCode blocks. The programmable components are as follows:
The 5×5 LED Matrix Display#
The 5×5 LED Matrix consists of 25 individually controllable light-emmitting diodes (LEDs). There are a series of blocks that allow the user to control the LEDs to display text and images.
The 5×5 LED Matrix is displayed below:
The General-Purpose Input/Output (GPIO) Pins#
The general-purpose input/output (GPIO) pins are special connectors that let you interact with the outside world. Think of them like tiny switches that can send signals (like turning on a light) or receive signals (like reading the state of a button). You can program these pins to control various gadgets like LEDs, sensors, or motors. For example, you could write a program that makes an LED blink or measure temperature with a sensor. GPIO pins are useful for building projects and learning how electronics and sensors work.
The GPIO pins are displayed below:
There are two types of GPIO pins on the micro:bit, alligator GPIO pins, and breakout board GPIO pins. The alligator GPIO pins can be accessed with alligator clips, as displayed below:
TODO: INSERT PHOTO OF MICRO:BIT WITH ALLIGATOR CLIPS
The breakout board GPIO pins are slip pins that cannot be accessed without a breakout board, a special board designed to expand the micro:bit’s capabilities and access to the GPIO pins.
Alligator GPIO Pins#
The most accessible pins are designed with holes with alligator clips to easily attach wires to these pins without needing any special tools. These pins are labeled 0, 1, 2, 3V, and GND. These labels help you know where to connect your wires when using alligator clips on these pins.
Alligator Input/Output Pins#
The alligator clip GPIO pins labeled 0-2 on the micro:bit let you connect the micro:bit to other electronic components, like lights, motors, or sensors. These pins can send signals to control these components or receive signals to get information from them, helping you create projects and experiments.
The alligator GPIO pins are displayed below:
Alligator 3V Pin#
The alligator 3V pin on the micro:bit provides a small amount of power, like a battery. You can use it to power other electronic components, like sensors or small lights, in your projects. This pin helps ensure your connected devices have the energy they need to work. The voltage rating of the micro:bit 3V pin is 3.3 volts often abbreviated 3v3.
The alligator 3V pin is displayed below:
Alligator GND Pin#
The pin labeled GND is the ground pin. A ground pin is like the zero-point in an electrical circuit. It helps complete the circuit by giving the electricity a path to flow back to, ensuring everything works correctly and safely in your project.
The alligator GND pin is displayed below:
Breakout Board GPIO Pins#
The other pins that are not labeled are only easily accessible using breakout boards specifically designed for the micro:bit. Some basic breakout boards available for micro:bit are displayed below:
Some breakout boards are designed to work with components that have special connectors, and some are designed to work with breadboards (the breakout boards on the left).
Breakout Board GPIO Pins#
The breakout board GPIO pins are smaller than the pins designed to be connected with alligator clips. It is possible to make contact with these pins, but they are small and close together, making a breakout board the best option when connecting them.
The breakout board GPIO pins are displayed below:
Breakout Board 3v3 Pins#
The breakout 3v3 pin on the micro:bit provides a small amount of power, as with the alligator 3v3. Breakout boards often have access to 3v3 voltage pin that is always on. This pin is used to power sensors. These pins can also be used to check if LEDs are working correctly.
Breakout Board GND Pins#
The breakout board functions just as the alligator ground pins. These pins are used to complete the circuit.
The A and B Buttons#
The A and B buttons on the micro:bit are like simple controls you can press to interact with your programs. You can program the micro:bit to do different things when you press these buttons, such as showing a message on the LED screen, playing a sound, or starting a game.
The Sound Sensor/Microphone#
The sound sensor/microphone on the micro:bit can sense sounds around it. It allows the micro:bit to detect noises, like clapping or talking, and then respond to them in your programs. For example, you could make the micro:bit light up when it hears a loud sound.
The Buzzer/Speaker#
The buzzer/speaker on the micro:bit can play sounds and music. You can program the micro:bit to make noises, play melodies, or create sound effects, which can be useful for games, alarms, or fun projects.
Accelerometer/Compass#
The accelerometer on the micro:bit senses movement and can tell how fast and in which direction the micro:bit is moving. The compass, also called a magnetometer, detects the Earth’s magnetic field and helps the micro:bit know which way is north. Together, these sensors can be used for activities like making a step counter or a digital compass.
Temperature Sensor#
The micro:bit’s temperature sensor measures how hot or cold it is around the device. It’s built into the processor (the micro:bit’s brain), so it can quickly read temperature information, which can then use this data to display the temperature on the LED screen or respond to changes in temperature in your programs. This temperature sensor is accurate between ±4°C.
The Captive Touch Inputs#
The BBC micro:bit has special pins that can sense touch, called captive touch pins. When you touch these pins, they can detect the tiny electrical charge from your body and respond, allowing you to control things like lights or sounds just by touching the micro:bit.
The Captive Touch Logo#
The captive touch logo on the micro:bit works like a touch-sensitive button. When you touch the logo, it can detect your touch and send a signal to the micro:bit’s processor, allowing you to interact with your programs in a fun and easy way, like turning on lights or starting a game.
The Captive Touch Pins#
The captive touch pins on the micro:bit are touch-sensitive spots, similar to the logo. When you touch these pins, they can detect your touch and send a signal to the micro:bit’s processor. This lets you interact with your programs in different ways, like controlling lights or sounds by simply touching the pins.
The Captive Touch GND#
To use the captive touch logo and pins on the BBC micro:bit, you need to connect the GND pin to something that you are touching, like holding a wire connected to it. This helps the micro:bit detect your touch more accurately because it completes the electrical circuit needed for the touch sensors to work properly.
The Bluetooth Antenna#
The BLE antenna on the micro:bit allows it to communicate wirelessly with other devices using Bluetooth. This means the micro:bit can send and receive information, like messages or sensor data, to and from phones, tablets, and other micro:bits without using any cables.
Non-Programmable Components#
There are several components that cannot be controlled using MakeCode blocks. The components are necessary for the micro:bit to function properly. The non-programmable components are as follows:
The Processor#
The processor on the micro:bit is like the brain of the device. It reads the instructions from your program and tells the micro:bit what to do, such as lighting up LEDs, reading sensors, or playing sounds. Without the processor, the micro:bit wouldn’t be able to follow any commands.
The Micro USB Connector#
The USB connector on the micro:bit lets you connect it to a computer using a USB cable. This connection allows you to transfer programs from your computer to the micro:bit and also powers the micro:bit so it can run those programs.
The Power Connector#
The power connector on the micro:bit is where you plug in a power source, like a battery pack or a USB cable. This power source gives the micro:bit the energy it needs to run your programs when it is not connected to the computer with a USB cord. Without power, the micro:bit can’t do anything.
The Reset Button#
The reset button on the micro:bit is like a restart button on a computer. When you press it, the micro:bit stops whatever it’s doing and starts over from the beginning, running the program you loaded onto it from the start. This is useful if your program gets stuck or if you want to quickly restart it without turning the whole device off and on.
