ITE-10 System Unit & Processor no q.pptx
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THE SYSTEM UNIT & THE PROCESSOR Elly Jay Amba Cennen Jay D. Col Nimrod P. Pala Johnmer J. Rabaya THE SYSTEM UNIT & PROCESSOR THE SYSTEM UNIT & PROCESSOR THE COMPONENTS OF THE PROCESSOR THE PROCESSOR: CONTROL UNIT The Control Unit or Program Control Unit, organizes...
THE SYSTEM UNIT & THE PROCESSOR Elly Jay Amba Cennen Jay D. Col Nimrod P. Pala Johnmer J. Rabaya THE SYSTEM UNIT & PROCESSOR THE SYSTEM UNIT & PROCESSOR THE COMPONENTS OF THE PROCESSOR THE PROCESSOR: CONTROL UNIT The Control Unit or Program Control Unit, organizes the sequence of micro-operations that need to be performed in order to carry out an instruction, including managing the other components in the processor. The following are the responsibilities of the control unit: decodes each and every instruction to ascertain the necessary action (such as loading data from main memory, performing a logic operation, or performing an arithmetic calculation) THE PROCESSOR: CONTROL UNIT The following are the responsibilities of the control unit: Transmits and receives control signals to and from other parts, allowing things like data loading and reading into and out of the main memory. Verifies the successful delivery of signals ensures that information is sent at the appropriate time and location. guarantees that instructions are carried out in the right order. THE PROCESSOR: ARITHMETIC AND LOGIC UNIT The Arithmetic and Logic Unit (ALU) is in charge of carrying out the following logical operations and arithmetic calculations: Addition, subtraction, multiplication, division Logical bitwise operations, such as AND, OR, NOT, and XOR Comparisons between values, such as greater than, less than, equal to Shifting binary patterns to the left or right THE PROCESSOR: REGISTER Registers are locations of very high speed computer memory within the processor. General-purpose registers are used to store the results of the intermediate calculations that are part of larger computations. Dedicated or special-purpose registers have a specific purpose within the fetch-decode-execute cycle. Their roles are specified below: THE PROCESSOR: REGISTER REGISTER PURPOSE Program Counter (PC) Holds the address of the next instruction to be executed by the processor. Current Instruction Register Holds the instruction that the (CIR) processor is currently executing. Memory Address Register (MAR) Holds the address of the memory location (in main memory) that the processor needs to access, either to read from (i.e. load data) or write (i.e. store data) to. THE PROCESSOR: REGISTER REGISTER PURPOSE Memory data register (MDR) Holds the data (data values or instructions) that are read from or written to the main memory. Accumulator Stores the result of any calculation processed by the ALU. Status register (SR) Stores information about the result of the last instruction that the ALU executed. Each bit within the status register acts as a flag to indicate if an error or exception has occurred within the process. The SR can also be 4 STEPS IN A MACHINE CYCLE 1. Fetch The fetch step involves several sub-steps: Program Counter (PC) Update: The CPU uses the program counter to determine the address of the next instruction to be executed. The Program Counter (PC) is a special register in the CPU that keeps track of the address of the next instruction to be executed in a program. Memory Access: The CPU sends a read request to memory, specifying the address stored in the PC. 1. Fetch The fetch step involves several sub-steps: Instruction Register (IR): The fetched instruction is loaded into the instruction register, where it will be held for decoding. 2. Decode Decoding is crucial for understanding what the fetched instruction entails: Instruction Breakdown: The instruction is parsed to identify its components, including the opcode and any operands. Control Signals Generation: The control unit generates specific signals based on the decoded instruction. These signals direct the CPU's operation by enabling or disabling specific components, such as the arithmetic logic unit (ALU), registers, or memory. 3. Execute During the execution phase, the actual operation specified by the instruction takes place: Operation Performance: If the instruction involves arithmetic or logical operations, the ALU performs the necessary calculations Data Movement: If the instruction requires data to be moved, the CPU will transfer data between registers or to/from memory. I/O Operations: If the instruction involves input/output operations, the CPU may communicate with peripheral 4. Store The store step is essential for maintaining the state of the CPU and memory: Result Storage: After execution, any results generated by the instruction are written back to the appropriate register or memory location. Update Flags: The CPU may also update status flags based on the results of the operation, which can affect the flow of subsequent instructions. Status flags are indicators in a CPU that reflect the results of operations. They monitor conditions guide control flow decisions, and help detect errors. Essentially, they assist the CPU in making decisions during program execution. 4. Store The store step is essential for maintaining the state of the CPU and memory: Preparation for Next Cycle: Finally, the system is prepared to begin the next machine cycle, starting back at the fetch step with the updated program counter. THANKS Elly Jay Amba Cennen Jay D. Col Nimrod P. Pala Johnmer J. Rabaya CREDITS: This presentation template was created by Slidesgo, including icons by Flaticon, infographics & images by Freepik https://adacomputerscience.org/concepts/arch_processor? examBoard=ada&stage=all
