1.1.1 Structure And Function Of A Processor Flashcards
What does the Arithmetic and Logic unit do?
The ALU completes all the arithmetic and logical operations
What is the Control Unit?
A part of the processor which directs operations inside the CPU
What are registers?
Small memory cells that operate at high speeds
Where do all the arithmetic, logic, or shift operations occur?
They occur in registers
What does the Program Counter (PC) do?
The PC holds the address of the next instruction to executed
In which part of the CPU do all the calculations take place?
Arithmetic and Logic Unit (ALU)
Where are the intermediate arithmetic and logic results stored
In the Accumulator (ACC)
What does the Memory Address Register (MAR) do?
Holds the address of a location that is to be read from or written to
What does the Memory Data Register (MDR) do?
Temporarily stores the data that has just been read from or the data that needs to be written to memory
What does the Current Instruction Register (CIR) do?
Holds the current instruction, the instruction is divided up into opcode and operand
What is a bus?
A set of parallel wires connecting two or more components together
What is a system bus?
The collection of the data bus, address bus, and control bus is called the system bus
What is the width of a bus?
The number of parallel wires it has
What is the data bus?
A bi-directional bus used to transport data and instructions between components
What is the control bus?
The bi-directional bus used to transmit control signals between internal and external components
What is the address bus?
Used to transmit the memory address specifying where data is to be sent from or retrieved from
What does adding a wire to the address bus do to
the number of addressable locations?
It doubles the number of addressable
locations
What does Bus Request indicate?
It indicates a device is requesting access
to the data bus.
What does Bus Grant indicate?
What does Bus Grant indicate?
Indicates the CPU has granted access to
the data bus
What does memory write do?
Causes the data on the data bus to be
written into the addressed location
What does memory read do?
Causes the data from the addressed
location to be placed onto the data bus.
What does the interrupt request control signal
indicate?
Indicates that a device is requesting
access to the CPU.
What is the clock control signal used for?
It is used to synchronise instructions.
What is Assembly Language?
Assembly Language is a programming
language where mnemonics are used to
represent instructions.
What is opcode?
Opcode is used to determine the type of
instruction and what hardware to use to
execute it.
What is the operand?
The operand is the address of where the
operation is performed.
What occurs during the fetch phase?
- The address from the PC is copied to the MAR,
- Instruction held at that address is copied to the
MDR by the data bus, simultaneously the
contents of the PC is increased by 1, - The value of the MDR is copied to the CIR
What occurs during the decode phase?
The contents of the CIR is split into
operand and opcode.
What occurs during the execute phase?
The opcode is executed on the data.
What is the clock speed?
The number of clock cycles completed
per second.
What is cache memory?
Cache memory is the CPU’s onboard
memory which can be accessed a lot
faster than main memory
What is pipelining?
The process of completing the fetch,
decode and execute of three separate
files simultaneously.
What is Von Neumann architecture?
Architecture in which there is a single
shared memory and shared data bus for
both data and instructions.
What is Harvard architecture?
Architecture in which there is two
separate memory and data buses for
data and instructions.
What is contemporary processing?
Processing in which Von Neumann
architecture is used for main memory.
Cache uses Harvard architecture, divided
into instruction cache and data cache
