Digital and Analogue Sensing

Using the lighthouse mimic When it is dark, we want the light on the lighthouse to flash on and off (output 1) When it is light, we want the foghorn to sound on and off (output 2)

Flowchart for the lighthouse

The DECISION box is checking to see if input 1 is either ON or OFF. This is a DIGITAL decision.

Analogue sensing task Open the mimic LIGHTHO2 Open the file lightho1 Edit the decision box so that the light flashes if the light level is LESS THAN 50 Save your file as lightho2

The decision box is now MEASURING the VALUE of the light This is an ANALGOUE decision

Light switches that you use at home are DIGITAL because the light is either ON or OFF If you have a dimmer switch the lights can be just on, half on, three quarters on or full on. This is an ANALOGUE device