1.1, The Purpose of the CPU
Computer systems - answer Electronic device that takes a set of digital inputs,
processes them and creates a set of outputs
CPU (Central Processing Unit) - answer Main purpose is to process data
Fetch - answer• Fetch the next instruction from main memory (RAM) through address
bus
• RAM sends instructions through data bus and brings it back to CPU
Decode - CU - answerWithin CPU the instructions are decoded in the Control Unit -
works out why needs to be done
Execute - ALU - answerCarries out the instruction, like performing a calculation
Arithmetic Logic Unit (ALU) - answerDoes basic decisions and instructions
Control Unit (CU) - answerDecodes instructions and controls how data moves around
the CPU to execute instructions
Cache - answerTo overcome delays in locatings and sending data to the CPU, the
instructions are copied to this memory
Registers - answerMemory locations in the CPU, can be accessed quickly
Von Neumann Architecture - answerA processor where data and instructions are stored
in the same memory and accessed via buses
Computer systems - answer Electronic device that takes a set of digital inputs,
processes them and creates a set of outputs
CPU (Central Processing Unit) - answer Main purpose is to process data
Fetch - answer• Fetch the next instruction from main memory (RAM) through address
bus
• RAM sends instructions through data bus and brings it back to CPU
Decode - CU - answerWithin CPU the instructions are decoded in the Control Unit -
works out why needs to be done
Execute - ALU - answerCarries out the instruction, like performing a calculation
Arithmetic Logic Unit (ALU) - answerDoes basic decisions and instructions
Control Unit (CU) - answerDecodes instructions and controls how data moves around
the CPU to execute instructions
Cache - answerTo overcome delays in locatings and sending data to the CPU, the
instructions are copied to this memory
Registers - answerMemory locations in the CPU, can be accessed quickly
Von Neumann Architecture - answerA processor where data and instructions are stored
in the same memory and accessed via buses
