~ Data Representation: Binary, Binary Arithmetic, Number Systems, ASCII, HEX, Memory and more....

Data Representation

The following presentation presents an interesting starting question - see if you can answer it, and then takes you through a recap on Binary, followed by Addition and Subtraction in Binary. Topics: Recap on Binary, Binary Addition, Binary Subtraction, Overflow Errors


Number Systems, Hexadecimal, ASCII


More on Hex

Converting Decimal into Hex

Character Encoding

Here we answer the question about how we represent TEXT in Binary...

ASCII specifically

Bits, bytes, MB,GB....and what's next?!

More on memory

End of Topic assessment

To EXCEL in this assessment, you will need to know the following:

  • Know the basis three number systems (base2,base10,base16)
  • Know that the Hex system contains digits: 0-9 and A-F
  • Know what the ASCII table does and why it is needed
  • Know the rules of addition and subtraction
  • Understand how to convert binary numbers into decimal and vice vera
  • Understand how to convert denary numbers into hexadecimal
  • Understand what is meant by overflow errors when adding or subtracting binary numbers
  • Be able to convert numbers into from deanery to hex, and binary to hex
  • Be able to write secret messages in binary and decode them using the ASCII table

Success Criteria - ask yourself if you can do the following.

You can convert numbers from binary to Decimal and vice versa

You can convert numbers from denary to HEX and if you're very clever, vice versa too!

You can ADD & SUB binary numbers taking into account overflow errors

You can describe what the ASCII table is used for

You can write secret messages into binary and decode them using the ASCII table


Key words - make sure you know these definitions

Key Word


(Once you know it, write in the meaning of each key word)
















Topic 6