Lesson activities for

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  Processor sets the read line on the control bus
  
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  Contents of the memory location are conveyed along the data bus into the processor
  
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  Processor places the address of the required memory location on the address bus
  

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  Processor places the data to be written to memory on the data bus
  
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  Processor places the address of the required memory location on the address bus
  
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  The data is conveyed along the data bus to the memory location
  
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  Processor sets the write line on the control bus
  

Search online for companies that sell memory (such as http://www.crucial.com/). Find three further facts about memory that you can share with the class.

Sort the following devices according to whether they are input or output devices.

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  Mouse
  
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  Speakers
  
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  Monitor
  
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  Touch screen
  
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  Keyboard
  
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  LED
  
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  Sensor
  
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  Microphone
  
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  Scanner
  
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  Printer
  
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  Web cam
  
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  Digital camera
  

In your group, identify all the input devices found on the digital computer you have been assigned.

Complete the table below to create a reference sheet for yourself.

In your group, identify all the output devices found on the digital computer you have been assigned.

Complete the table below to create a reference sheet for yourself.

Check the system settings of your digital computers or search online for their technical specifications to find out the type of storage you are using.

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  Do the following:
  
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    Save a file onto the magnetic hard disk drive.
    
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    Burn a file on to a CD or DVD.
    
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    Save a file on to a solid state drive or a memory stick.
    

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  Now describe in your own words how the data in the file was stored on each of these types of storage.
  

Use the labels below to complete the diagram.

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  Memory
  
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  Control unit
  
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  Arithmetic and logic unit (ALU)
  
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  Registers
  

Control bus

Address bus

Data bus

The first column of the table contains some assembler instructions for the ARM1176JZ-S processor. Match each assembler instruction with the correct action and underline the part of the action that helped you know which assemble instruction it relates to. One has been done for you.

Use the labels below to complete the diagram on the next page. The diagram shows how high level programs are translated into machine code so that they can be run by the CPU.

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  Python (high level language)
  
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  Machine code
  
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  Compiler
  
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  Assembly language (low level language)
  
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  Assembler
  

Complete this diagram of the fetch-decode execute cycle using the labels below.

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  FETCH
  
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  DECODE
  
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  EXECUTE
  
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  Fetches the next instruction from memory and increments program counter
  
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  Decodes the bit pattern (machine code) into the instruction to be executed
  
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  Executes the instruction and stores the results in memory or registers
  

Guess how many fetch-decode-execute cycles are happening in the classroom at this moment! Write your guess here:

Now you’re going to do a proper estimate!

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  Estimate the number of digital computers (desktops, laptops, tablets, mobile phones, etc.) in the room:
  
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  Assuming a clock speed of 1 GHz for each digital computer and that each fetch-decode-execute cycle takes 10 instructions, calculate the number of fetch-decode-execute cycles taking place per second.
  

Sort these stages of the fetch-decode-execute cycle into the correct order:

Increment the program counter to point to the next instruction

Decode the instruction

Store results in a register

If the instruction uses data from memory, identify the memory addresses and fetch the data from memory

Fetch the next instruction from main memory using the memory address in the program counter register

Execute the instruction

Label or colour code this assembly language instruction to show the opcode, and the destination and input operands.