Computer Systems

Describe and exemplify the use of binary numbers to represent positive integers.

Convert from binary to denary and vice-versa.

Describe floating point representation of positive real numbers using the terms mantissa and exponent.

Describe extended ASCII code (8-bit) used to represent characters.

Describe the vector graphics method of graphic representation for:

• rectangle

• ellipse

• line

• polygon

with attributes:

• co-ordinates

• fill colour

• line colour

Describe the bit-mapped method of graphics representation.

Describe the purpose of the basic computer architecture components and how they are linked together:

• processor (registers, ALU, control unit)

• memory locations with unique addresses

• buses (data and address)

Explain the need for interpreters and compilers to translate high-level program code to binary (machine code instructions).

Environmental impact

Describe the energy use of computer systems, the implications on the environment and how these could be reduced through:

• settings on monitors

• power down settings

• leaving computers on standby

Describe the role of firewalls

Describe the use made of encryption in electronic communications