Control : Software

The software used in a control system will regularly take readings from the sensors. Using this information the software must decide which devices to turn on or off.

When the control system is designed the user must input into the system the information it needs to take these decisions. This information will be in the form of an algorithm which describes when to take readings and under what conditions the different devices should be turned on and off.

The user would normally plan the algorithm using a flowchart, then input it into the computer using a programming language such as Logo.

This example shows the algorithm used to operate a very simple control system for a doorbell. When the button is pressed the bell sounds until the button is released.

The algorithm would be converted into a program and entered into the computer that will run the control system.

You can view the algorithm used to control three other systems later in the notes.

Example Control Systems
Traffic Lights
Simple Greenhouse
Advanced Greenhouse

GCSE ICT Companion 04 - (C) P Meakin 2004