Microprocessor - Yousef's Notes
Microprocessor

Microprocessor

#Types

#8086 (First x86)

  1. Instruction Register and Decoder: These components fetch, decode, and execute instructions. The instruction register holds the current instruction, while the decoder interprets it.

  2. Control Logic: Manages control signals for executing instructions, coordinating the microprocessor’s operations.

  3. General Purpose Registers:

▪ AH, AL, BH, BL, CH, CL, DH, DL: These are 8-bit registers that can be combined into 16-bit registers (AX, BX, CX, DX) for various operations.

▪ SP (Stack Pointer): Points to the top of the stack in memory, used for subroutine and interrupt handling.

▪ BP (Base Pointer): Primarily used for accessing parameters in stack frames.

▪ SI (Source Index) and DI (Destination Index): Used for indexed addressing and string operations.

  1. Arithmetic Logic Unit (ALU): Performs arithmetic and logic operations, interacting with the registers and temporary registers.

  2. Temporary Registers (TEMP): Hold intermediate data during operations, assisting the ALU.

  3. Internal Data Bus: A 16-bit bus for data transfer within the microprocessor.

  4. Address Bus: A 16-bit bus used to address memory locations.

  5. Buffers: Facilitate data transfer between internal components and external peripherals or memory.

#RISC-V

  1. Instruction Register and Pre-Decoder: The instruction register holds the current instruction. The pre-decoder prepares instructions for decoding by breaking them down into simpler parts.

  2. Decode and Optimize: This stage interprets the instruction and optimizes it for efficient execution. The branch predictor helps determine the flow of control, improving pipeline efficiency.

  3. Control Logic: Manages control signals for executing instructions, coordinating the processor’s operations.

  4. Registers:

▪ 32 Integer Registers: General-purpose registers used for arithmetic, logic, and data manipulation.

▪ 32 Floating Point Registers: Used for floating-point operations, enhancing computational capabilities.

  1. Arithmetic Logic Unit (ALU): Performs arithmetic and logic operations, interacting with the integer and floating-point registers.

  2. Floating Point Unit (FP Unit): Dedicated to handling floating-point calculations, improving performance for complex mathematical operations.

  3. Load/Store Unit: Manages data transfer between memory and registers, adhering to the load/store architecture principle.

  4. Data Registers: Temporary storage for data being processed or transferred.

  5. Internal Data Bus: A 32-bit bus for data transfer within the processor.

  6. Address Bus: A 32-bit bus used to address memory locations.

  7. Buffers: Facilitate data transfer between internal components and external peripherals or memory.

#Z80

Used in calculators.

The Z80 architecture is a microprocessor architecture with several key components illustrated in the diagram:

  1. Instruction Register and Decoder: These components fetch, decode, and execute instructions. The instruction register holds the current instruction, while the decoder interprets it.

  2. Control Logic: Manages control signals for executing instructions, coordinating the processor’s operations.

  3. Registers:

▪ General Purpose Registers: B, C, D, E, H, L and their alternate pairs B’, C’, D’, E’, H’, L’. These are used for various data operations and can be paired for 16-bit operations.

▪ IX and IY: Index registers used for advanced addressing modes.

▪ A and A’ (Accumulator): Used for arithmetic and logic operations.

▪ F and F’ (Flags): Store the status of operations (zero, carry, etc.).

  1. Program Counter (PC): A 16-bit register that holds the address of the next instruction to be executed.

  2. Stack Pointer (SP): Points to the current top of the stack in memory, used for subroutine and interrupt handling.

  3. Multiplexers (MUX): Allow selection between different data sources for processing.

  4. Arithmetic Logic Unit (ALU): Performs arithmetic and logic operations, interacting with the accumulator and other registers.

  5. Temporary Register (TEMP): Holds intermediate data during operations, assisting the ALU.

  6. Internal Data Bus: An 8-bit bus for data transfer within the microprocessor.

  7. Address Bus: A 16-bit bus used to address memory locations.

  8. Buffers: Facilitate data transfer between internal components and external peripherals or memory.

#AVR

Arduino

  1. Instruction Register and Decoder: These components fetch, decode, and execute instructions. The instruction register holds the current instruction, and the decoder interprets it.

  2. Control Logic: Manages control signals for executing instructions, coordinating the microcontroller’s operations.

  3. 32 General Purpose Registers: These registers are used for data manipulation and storage. They allow for efficient data handling and quick access during operations.

  4. Program Counter (PC): A 16-bit register that holds the address of the next instruction to be executed, enabling sequential instruction fetching.

  5. Stack Pointer (SP): Points to the current top of the stack in memory, used for subroutine and interrupt handling.

  6. Index Registers (IX, IY): Used for addressing and accessing data within memory, aiding in complex data operations.

  7. Arithmetic Logic Unit (ALU): Performs arithmetic and logic operations, interacting with the general-purpose registers and accumulators.

  8. Accumulator (ACU): Used in conjunction with the ALU for arithmetic and logic operations, holding intermediate results.

  9. Multiplexer (MUX): Allows selection between different data sources for processing.

  10. Internal Data Bus: An 8-bit bus for data transfer within the microcontroller.

  11. Address Bus: A 16-bit bus used to address memory locations.

  12. Buffers: Facilitate data transfer between internal components and external peripherals or memory.

#8051

The 8051 architecture is a microcontroller architecture that includes several key components, as illustrated in the diagram:

  1. Instruction Register and Decoder: These components are responsible for fetching, decoding, and executing instructions. The instruction register holds the current instruction, while the decoder interprets it.

  2. Control Logic: Manages the control signals for the execution of instructions, coordinating the operation of the processor.

  3. Program Counter (PC): A 16-bit register that holds the address of the next instruction to be executed, enabling sequential instruction fetching.

  4. Data Pointer (DPRTR, DPH, DPL): A 16-bit register used to store memory addresses, often for indirect addressing in data transfer operations.

  5. Accumulator (ACU) and Register A: The accumulator is an 8-bit register used for arithmetic and logic operations. It is a key part of the Arithmetic Logic Unit (ALU).

  6. Arithmetic Logic Unit (ALU): Performs arithmetic and logic operations. It interacts with the accumulator and other registers to process data.

  7. Temporary Register (TEMP): Holds intermediate data during operations, assisting the ALU in calculations.

  8. Internal Data Bus: An 8-bit bus used for data transfer within the microcontroller.

  9. Address Bus: A 16-bit bus used to address memory locations.

  10. Buffers: Facilitate data transfer between the internal components and external peripherals or memory.

#IA64 (Itanium)