Programmable Components and Flowcharts
How a programmable component uses a flowchart to switch outputs on and off in response to inputs and decisions, including analogue inputs and simple routines.
Revise this, the fun way
Play it interactively, earn XP and build a streak, free.
Start revising freeWhat you'll cover
Machines that follow instructions 🤖
A **programmable component**, such as a microcontroller, is a tiny computer built into a product. It runs a **program** that reads **inputs** and switches **outputs** on and off automatically. Designers plan that program as a **flowchart**: a diagram of the steps and decisions the component follows. In this module you will read, complete and design simple flowcharts.
The flowchart symbols 🔑
A flowchart is built from a few standard shapes:
Match each symbol 🔗
- Terminal (rounded box)
- Parallelogram
- Rectangle
- Diamond
- Marks the start or stop of the program
- Reads an input or switches an output
- An action the component carries out
- Asks a yes/no question and branches the flow
Read the flowchart 🪜
An interactive activity.
Which symbol? 🎯
Which flowchart symbol is used for a decision that asks a yes/no question?
- A diamond
- A rectangle
- A parallelogram
- A rounded box
Digital and analogue inputs ⚖️
A programmable component can read two kinds of input.
Spot the analogue inputs ✅
Select the TWO inputs that are analogue.
- An LDR light sensor
- A thermistor temperature sensor
- A push-to-make switch
- An on or off toggle button
Responding to analogue inputs 💡
Because an analogue input gives a **range** of values, the program compares the reading to a set **threshold**. For example: IF the light level is below the threshold, THEN switch the LED on. Programs also use simple **routines** to control timing and repetition: a **delay** waits for a set time, a **loop** repeats steps, and a **count** keeps track of how many times something happens.
Programmable logic in words 🧱
A flowchart begins and ends with a _____ symbol. A _____ symbol, shaped like a diamond, asks a yes/no question. A programmable component reads an _____, such as a switch or a sensor, then switches an _____, such as an LED, on or off. A sensor that gives a range of values, like an LDR, is an _____ input.
Inputs or outputs? 🖍️
An interactive activity.
Work the flowchart 🧭
An interactive activity.
Describe the system ✍️
An interactive activity.