Processor Components And Storage Devices Flashcards
CPU
Central Processing Unit (Processor) - made up of components and has pins made of gold
MAR
Memory Address Register - Holds the address in memory where processor is required to fetch/store data from/to
MDR
Memory Data Register - Temporarily holds data moving between processor and main memory
CIR
Current Instruction Register - Holds current instruction which is made of opcode and operand
Opcode
The part of the instruction that tells the processor what should be done
Operand
The part of the instruction that contains the data to be acted on, or the memory location of the data in a register
PC
Program counter - holds memory address of next instruction to be executed
Accumulator
Stores results from ALU
Several locations of super-fast memory called registers
Processor is able to access and reuse results in subsequent calculators
Memory Read
Causes data from addressed location in RAM to be placed on the data bus
Memory Write
Causes data on data bus to be written into addressed location on RAM
Bus Request
Indicates device is requesting use of data bus
Bus Grant
Indicates CPU has granted access to data bus
ALU
Arithmetic-Logic Unit
The problem-solving part of the processor
Arithmetic
Add, subtract, multiply, divide
Logical
and, or, not, xor
Shift
move bits to left/right within a register
Fetch execute cycle
Fetch -> Decode -> Execute -> Repeat