Exploring input and output
Unit Exploring input and output
Year level: 3-4 Topic: Digital Systems Time: 7 hours
Digital systems store, process and transmit information in digital form. A computer, notebook, tablet and smartphone are all examples of digital systems. Connecting other digital components (peripherals) to a digital system enables different functions; for example, a simple circuit board can be used as an input device, replacing keystrokes on a keyboard. This opens up the possibility of using a range of materials for input, allowing creativity in design.
A programming board enables the use of different inputs; for example, a push button to initiate an action; or a sensor to gather data such as temperature or light levels. Similarly, a snap-together circuit can have components such as a power supply, motor (servos), sensors, lights, buzzers, switches, and Bluetooth connectivity – enabling remote control. The device can often be programmed using a visual programming language, which allows students to integrate understandings of inputs and outputs of digital systems with programming a digital solution.
The circuit board, programming board and snap-together circuits suggested in this sequence are examples generally used by schools. It is envisaged that rather than incorporate all three devices or invention kits that schools focus on one and explore its functionality and then incorporate student design and implementation of a digital solution. There is no requirement to explore all three; rather, the intention is to cater for what resources schools may have or decide to purchase.
Flow of Activities
Input devices
Introduce the Makey Makey circuit board to explore alternative input devices.Connecting a circuit
Explore inputs and outputs using snap-together components connected in a circuit.Exploring a programmable board
Explore inputs and outputs using a programmable board such as BBC Micro:bits or Codebug.Digital system project
Create a digital solution that incorporates user input.Activity Input devices
What alternative input devices can I use?
Australian Curriculum Alignment
- Digital systems (ACTDIK007)
What's this about?
Makey Makey is an invention kit available for purchase that allows you to interact with a computer, using everyday objects as a replacement for inputs such as a keyboard or computer mouse.
The Makey Makey board will plug directly into the computer’s USB peripheral port and essentially behave like an input device. When specific keys are pressed the Makey Makey board can mimic those keystrokes.
Activating a key means creating a closed circuit. For the circuit to work, electrons have to be able to flow from the Makey Makey input key to Makey Makey’s ground. So materials chosen as the input must conduct some level of electrical energy; that includes such things as aluminium foil, a banana and even a circuit drawn in grey lead pencil.
Learning tasks
- Revise input devices and in particular the relationship between input devices the computer and software and an output. List the different types of input devices including keyboard, mouse and joystick.
- Explore the range of Makey Makey projects available on the internet to get students excited about exploring input devices.
- Ask students to connect a simple circuit. Have them choose one item, for example a banana, as the input and make sure it works. This idea can then be extended; for example, joining up more bananas and connecting these to arrow inputs and the space bar on the keyboard to play an online piano.
Supporting Resources



Lesson Ideas
Assessment
Describe how a range of digital systems (hardware and software) and their peripheral devices can be used for different purposes.
Suggested approaches may include
- Have students explain their Makey Makey system and the choice of material for input.
OR
- Students annotate a drawing of their Makey Makey system.
Activity Connecting a circuit
How can I connect components in a circuit to my digital system?
Australian Curriculum Alignment
- Digital systems (ACTDIK007)
What's this about?
Electronic kits that use snap-together components such as LittleBits enable students to explore simple circuitry that can be incorporated into a digital system.
The LittleBits kit, for example, has a number of inputs such as buttons, dimmers and sensors. These send signals to the circuit. The kit also has outputs such as a buzzer, motor and light. The Bluetooth bit enables students to remotely control elements such as sliders. Other similar kits may vary in components and capabilities.
Learning tasks
- Explore the snap-together components to create a simple circuit.
- Start off by setting simple challenges. Examples of challenges are connecting a circuit that:
- provides a light, sound or movement
- provides a light that pulses or that can be dimmed or made brighter
- provides movement that can be made faster or slower.
- More challenging tasks
- Create movement (servo) or light (LED) using the sound sensor (for example, clapping to activate a component).
- As a further challenge you could include Bluetooth control. The LittleBits Bluetooth Low Energy (BLE) bit enables students to control their inventions wirelessly, from a smartphone or tablet. To do this you need the LittleBits Invent app and the BLE bit to move motors on wireless vehicles, or trigger buzzers.
Supporting Resources





Assessment
Describe how a range of digital systems (hardware and software) and their peripheral devices can be used for different purposes.
Suggested approaches may include
- Have students explain their system of snap-together components in a circuit and the choice of input and its corresponding output.
Activity Exploring a programmable board
Why connect a programming board to my digital system?
Australian Curriculum Alignment
- Digital systems (ACTDIK007)
What's this about?
A programming board, such as a Micro:bit or Codebug, can have different inputs. For example, a push button can initiate an action. Different sensors can gather data such as temperature or light levels; or can detect movement of the device using an accelerometer.
The different actions or events can be programmed via easy-to-use software provided on the relevant website.
Learning tasks
- Use the Micro:bit emulator or the Codebug emulator to explore inputs and outputs.
- Coding examples include:
- INPUT on ‘button A pressed’ select an output such as MUSIC play tone Middle C for 1 beat.
- INPUT on ‘shake’ select an output such as BASIC Show LEDs.
- For more challenging tasks, investigate the light levels. Use a variable for light level.
-
INPUT on ‘button A pressed’ select an output such as BASIC Show LEDs.
However, you need to first add a VARIABLE block ‘set item to’ and change item to Light level. Then replace Show number to Light level.
-
- You can follow the same logic to record temperature.
- INPUT on ‘button A pressed’ select an output such as BASIC Show LEDs. However, you need to first add a VARIABLE block ‘set item to’ and change item to temperature. Then replace Show number to Temperature.
- The code can be downloaded to a physical Micro:bit if the school has purchased these devices.
Supporting Resources






Assessment
Describe how a range of digital systems (hardware and software) and their peripheral devices can be used for different purposes.
Suggested approaches may include
- Have students explain their programming board system, the choice of input and the corresponding output.
Activity Digital system project
Can I design and control a digital solution using my digital system?
Australian Curriculum Alignment
- Digital systems (ACTDIK007)
- Investigating and defining (ACTDIP010)
- Generating and designing (ACTDIP011)
What's this about?
Makey Makey, together with a visual programming language such as Scratch, Snap or similar, is a useful combination of tools that can be used to create digital solutions, as well as teach the basics of circuity, conductive materials and algorithms.
The Makey Makey board will plug directly into the computer’s USB peripheral port and essentially behave like an input device.
You can program Makey Makey in Scratch to respond in certain ways when specific keys are pressed; Makey Makey will then mimic those keystrokes.
The Micro:bit, Codebug or LittleBits electronics kit provide students with the opportunity to design a digital solution for their own project.
Learning tasks
- Offer students an opportunity to explore the Makey Makey, Micro:bit, Codebug or LittleBits electronics kit.
- Tell students that they will be creating a digital solution for their own project.
- Give students some time to explore possible projects and to design their solution on paper before implementation.
- The following are examples of projects that students could undertake.
- Makey Makey
- Create a sound machine.
- Create a game controller.
- Micro:bit or Codebug
- Create a compass that helps you find north.
- Create dice to use in a board game.
- LittleBits or similar electronics kit
- Create an animal that moves in response to the sound of your voice.
- Create your own alarm for a treasure box.
- Control a light remotely.
- Ask students to present their project and explain the input and corresponding output.
Supporting Resources


Lesson Ideas



Assessment
Describe how a range of digital systems (hardware and software) and their peripheral devices can be used for different purposes.
Suggested approaches may include
- Have students present their project and use a peer review to provide feedback.