The CPUThe CPU is the Central Processing UnitThe CPU is the brain of the computer system.
It processes all of the data and instructions that make the system work.The processing power of a CPU depends on different characteristics, like its clock speed, number of cores and cache size.The CPU architecture describes the main components of the CPU, how they interact with each other, and with other parts of the computer system. Von Neumann and Harvard are the two main types of architectureThe CPU has Three Main PartsThe Control UnitThe control unit is in overall control of the CPU. Its main job is to execute program instructions by following the fetch decode execute cycle. It controls the flow of data inside the CPU and outside the CPU.The Arithmetic Logic UnitThe ALU basically does all the calculations.
It completes simple addition and subtraction, compares the size of numbers and can do multiplications and divisions using repeated addition and subtraction. It performs logic operations as AND, OR and NOT and binary shifts. It contains the accumulator register.The CacheThe cache is very fast memory in the CPU. It’s slower than the registers but faster than RAM. It stores regularly used data so that the CPU can access it quickly the next time it’s needed.
When the CPU requests data, it checks the cache first to see if the data is there. If not, it will fetch it from RAM. Caches have a very low capacity and are expensive compared to RAM and secondary storage. There are different levels of cache memory – L1, L2 and L3. L1 is quickest but has the lowest capacity.
L2 is Slower than L1 but can hold more. L3 is slower than L2 but can hold more.The CPU contains various registers which temporarily hold tiny bits of data needed by the CPU. They are super quick to read/write to, way quicker than any other form of memory. You need to know about the program counter, memory address register, memory data register and the accumulator