Microprocessor and applications

Revisiting Block diagram of computer system

Microprocessor

• Process data from sensors
• Produce output through actuators
• Data can also be stored (with storage devices) and send through network
• Microprocessor works with digital data only

Sensors

• One type of input devices
• Automatically collects data from physical environment
• Data collected from environment is in analog form
• Require ADC (Analog to digital converter) to convert data from analog to digital

Actuators

• One type of output devices
• Output to physical environment in the form of e.g.:
  • Light
  • Movement
  • Heat
  • etc.
• Accepts data in analog form. So DAC (Digital to Analog Converter) is required

Activity

• Research online, find about Micro:bit's
  • Input devices / Sensors
  • Output devices / Actuators
  • Processor unit
  • Storage capacity
• Put in your notebook

Digital and analog data

Digital

• Discrete values
• Microprocessor can only process digital data

Analog

• Continuous values
• Physical data from the environment are analog
• (Usually) Sensor and actuators are analog

Analog example

Monitoring and measurement applications

• Applications to continuously monitoring the (physical) variables in the environment
• Data will be recorded (Data Logger)
  • ​To analyse the data
• Some application will report on abnormal activity
  • By actuators
  • Through network

Activity (Weather data)

1. In the notebook, write down as many physical variables (something you can measure) that are monitored by weather station (3 minutes)
2. Stand up and exchange the findings with classmates (3 minutes)
3. Share in class

Weather stations

• Automatically gather data from the environment
• The data are gathered 24/7 and...
  • ___________ in the computer (data-logging)
  • send to the centralize database through ________
• The data gathered can then used as...
   

Measuring Pollution in river

1. To monitor pollution, what kind of physical variables need to be monitored?
2. How do the we / computer know if the river is polluted?
3. Suggest why do we need more than one set of same sensors.
4. What will the system do after those data is collected?

1. Monitoring pollution can be done by collecting sample and perform test manually. Try to list two advantages and disadvantages of using computer system to do this. 

Why and why not computer?

Group presentation - topic 1

A large jewelry shop is looking for a system to prevent intruders to enter the premises during night time. Your team is a security system provider and try to persuade the shop to use your system. 

In the presentation, you should include:

1. What kind of sensors, and where are you going to place them
2. How is the system activated
3. What will happen if there's intruders, how can it minimize loss of the shop

Group presentation - topic 2

A hospital is looking for a system to monitor in-patient's vital sign, and alert the nurse/doctor if anything happens. This might include (but not limited to) heart rate, body temperature.  

In the presentation, you should include:

1. What kind of sensors and input devices needed
2. How and when will the alert triggered (on what conditions e.g.)
3. How to alert the nurse/doctor

Group presentation

• Presentation on 22/6
• Group of 4 students

Grading criteria:

• 40% on clearly describing your system and fulfilling all the required content
• 20% on reasonable technology (sensors/actuators etc) used
• 20% on block diagram / product brochure (prepare 7 hard copies before class) 
• 20% creative and professional presentation (remember you are a company bidding for the job)

Control applications

• Similar to monitoring applications, the sensors and processor will continuously monitoring the environment
• Base on the sensor readings, the processor may take different actions through actuators
• Actuators outputs to the environment, which will "affect" what the sensor is monitoring, thus forms the "feedback" or a "loop"

Electric water kettle

• Consider an electric water kettle with the functions displayed in the picture
• List the sensors and actuators used
• Draw the block diagram of it. 

Central heating system - radiator