1. 01/05/2015 Input-Output-Process Demo Automatic Streetlight System

2. 01/05/2015 Preset Value: Dark light level programmed in. Processor Input

3. 01/05/2015 Processor Light Sensor Input Measurement Light readings The monitoring of physical variables without the microprocessor taking action.

4. 01/05/2015 Processor Compares current light level with preset value Processing

5. 01/05/2015 Processor If current light level < preset value Light On Signal Night time Processing Control When a microprocessor takes action depending on sensor readings.

6. 01/05/2015 Light On Night time Output

7. 01/05/2015 Processor If current light level > preset value Light Off Signal Daytime Processing Control When a microprocessor takes action depending on sensor readings.

8. 01/05/2015 Light Off Output The process is continuous and so repeats.

9. Notes: Input: User sets the desired preset value. User sets the desired preset value. Sensors sending readings. Sensors sending readings.Processing: Microprocessor comparing the preset value with the current sensor readings. Microprocessor comparing the preset value with the current sensor readings. If higher / lower then microprocessor decides to switch a device on / off. If higher / lower then microprocessor decides to switch a device on / off.Output: Devices actually being switched on or off. Devices actually being switched on or off. Sensors do not compare or decide to switch anything on or off, they only send current readings. 01/05/2015