1.1.1 Structure & function of the processor - Filip Flashcards
what’s the purpose of the data bus ?
bi-directional bus used for transferring data between the ram and the CPU
what’s the purpose of the MDR ?
Stores the data of the instruction currently being executed
what’s the purpose of the MAR ?
To hold the address of the instruction currently being executed so that the data bus can retrieve the data
what’s the purpose of the CIR ?
holds the current instruction being executed divided into opcode and operand
what’s the purpose of the ALU ?
To solve mathematic problems presented to it
what’s the purpose of the Accumulator ?
holds the results of the ALU
what’s the purpose of Address bus ?
used to transmit the memory addresses of data between the MAR and Ram
what’s the purpose of the Control bus ?
bi-directional bus used to transmit control signals
what’s the purpose of the Program counter ?
holds he address of the next instruction to be executed
what’s the purpose of the FDE cycle ?
FDE cycle is used to process and execute instructions
describe the key term “holds he address of the next instruction to be executed”
program counter
describe the key term “bi-directional bus used to transmit control signals”
control bus
describe the key term “used to transmit the memory addresses of data between the MAR and Ram”
address bus
describe the key term “holds the results of the ALU”
accumulator
describe the key term “To solve mathematic problems presented to it”
ALU
describe the key term “holds the current instruction being executed divided into opcode and operand”
CIR
describe the key term “To hold the address of the instruction currently being executed so that the data bus can retrieve the data”
MAR
describe the key term “Stores the data of the instruction currently being executed”
MDR
describe the key term “bi-directional bus used for transferring data between the ram and the CPU”
Data bus
purpose of a register
temporary storage/memory location inside the CPU
used for a single specific purpose
factors affecting cpu performance
Cache
Number of cores
clock speed
purpose of multi core systems
can execute multiple instructions simultaneously.
More cores generally mean better performance, especially for software that can use multiple cores to execute tasks concurrently.
disadvantage of multi core systems
However, not all software can leverage multiple cores effectively, and therefore gains in performance may not be linear with increased cores.
purpose of cache
accessing cache is faster than RAM
properties of von Neuman architecture
all data and instructions are stored in a single memory space
shared data and address bus cause bottleneck issues
properties of Harvard architecture
parallel instructions and data access
more efficient memory usage
suitable for embedded systems
purpose of accumulator in FDE cycle
Holds all inputrs/outputs
stores the result from the ALU
checks for conditional branching e.g brz
stores data which has came from the MDR/RAM
Opcode
Opcode (short for operation code) is a portion of a machine language instruction that specifies the operation to be performed. It is a collection of bits that represents basic operations such as addition, subtraction, multiplication, complement, and shift
Operand
Operand is the part of the instruction that specifies the data to be operated on or the address of the data. Operands can be immediate values, register addresses, or memory addresses.
additional purpose of the program counter
pc is incremented by 1 every clock cycle
change by branch/jump instructions
