The Cpu and embedded systems

• What are the 3 main parts of the CPU:

  Control unit

  Arithmetic Logic Unit

  Cache
• Control Unit:

  Main job is to do fetch , decode , execute instructions

  Controls the Flow of data inside the CPU and outside the CPU
• Arithmetic logic Unit:

  Dose logical and arithmetic operations
• Cache:

  Very fast memory

  Stores regularly used data
• Von Neumann's architecture:

  Programs and data are stored into 1 memory
• CU stores the Program Counter

  ALU stores the accumulator

  The registers hold MAR and MDR
• Embedded systems are computers built into other devices

  e.g. TVs and Microwaves
• Accumulator:

  Stores intermediate results of calculations in the ALU
• Benefits or embedded systems:

  Cheaper to make

  Easier to design

  More efficient when doing their task
• Memory data register:

  Holds the instruction that may have to be fetched or waiting to be written to memory
• Memory Address Register:

  Holds any memory address that is about to be used by the CPU
• Program counter:

  holds the memory address of the instruction