1.1.1 structure and function of the processor Flashcards
also includes piplining
ALU
Airtimetic and logic unit
completes all the mathematical and logical operations.
Arithmetical operations = + -
Logical operations include boolean logic operations such as AND, OR, NOT, and XOR.
The Control Unit
directs the operations of the CPU
* Controlling and coordinating the activities of the CPU
* Managing the flow of data between the CPU and other devices
* Accepting the next instruction
* Decoding instructions
* Storing the resulting data back in memory
Program Counter (PC)
Holds the address of the next instruction to be executed
Accumulator (ACC)
Stores the results from calculations
Data Bus
This is used for transporting data and instructions between components
This is a bi-directional bus (meaning bits can be carried in both directions).
Address Bus
Holds addresses being sent to/from the CPU and RAM
The width of the address bus is proportional to the number of addressable memory locations.
Control Bus
a bi directional bus which Sends Signals to determine whether the other buses are in read or write mode
Pipelining
the process of completing the FDE cycles of three separate instructions simultaneously, holding appropriate data in a buffer in close proximity to the CPU until it’s required.
While one instruction is being executed, another can be decoded and another fetched.
This allows more instruction to be executed per second
aims of pipelining
Pipelining is aimed to reduce the amount of time CPU is kept idle. It is separated into instruction pipelining and arithmetic pipelining.
instruction pipelining
Instruction pipelining is separating out the instruction into fetching, decoding, and executing
arithmetic piplelining
Arithmetic pipelining is breaking down the arithmetic operations and overlapping them as they are performed.