COMPUTER SCIENCE AND ENGINEERING
COMPUTER ARCHITECTURE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
The CPU makes sense of the instructions.
|
|
|
The CPU fetches the information from RAM.
|
|
|
The instructions are executed.
|
|
|
None of the above
|
Detailed explanation-1: -Now, the instruction needs to be decoded. It is sent via the data bus to the control unit, where it is split into two parts. The first part is the operation code or opcode, which in this example CPU is the first four bits.
Detailed explanation-2: -In the decode part of the cycle, the control unit works out what the instruction is and sends signals to coordinate the other components. Lastly, during the execute part of the cycle, the instruction is executed, using the ALU if necessary.
Detailed explanation-3: -The CPU works by following a process known as ‘fetch, decode and execute’. The CPU fetches an instruction from memory, decodes this instruction and then executes it. The CPU carries out this cycle continuously, millions of times per second.
Detailed explanation-4: -Decode stage The decoding process allows the CPU to determine what instruction is to be performed so that the CPU can tell how many operands it needs to fetch in order to perform the instruction. The opcode fetched from the memory is decoded for the next steps and moved to the appropriate registers.
Detailed explanation-5: -The basic operation of the Central Processor Unit utilises what is called the ‘fetch-decode-execute’ cycle. The CPU is designed to load, read and execute a set of instructions – the CPU instruction set. It fetches the instructions from the main memory, decodes them, and executes them.