Microprocessor

Humidity sensorMisture sensorTemperature sensorpH sensorlight sensor

If not

keypad

Deviceson or off

Microprocessor

Turtlegraghics

preset value

ADC

compare set temperature with current temperature

current temperature

Automaticoven/cooker

start timeend timecooking temperaturetemperature sensor

Devices under computer control

FORWARDBACKWARDLEFTRIGHTPEPEATENDREPEATPENUPPENDOWN

Compares datapreset value

DAC

Boiler

Computer processing

heater switch off

Little turtle draws diagrams

Digital data

sensor

Current pHor=3.5

Chemicalprocesscontrol

Current pH3.5

Temperaturesensors

heating elements switch on

Computer

Centralheatingsystems

Set time=Current time

Key in requireddata

acid is added

Key in instructions

acid is closed

Timesensors

Current timeor=70℃

Temperature sensor

heater switch on

heating elements switch off

compare set time with current time

pH sensor

Temperaturedata

Glasshouseenvironmentcontrol

Current T70℃

Water pump

Temperature sensorspH sensors

End time=Current time

Sensors taking readings from surroundings