University:
Mt. San Antonio College
Course:
ELEC 74 | Microprocessor Systems
Academic year:

2024
Views:

272

Pages:

2
Author:

Dipin K.

8086 Architecture: The 8086 microprocessor, introduced by Intel in 1978, represented a significant leap forward in the realm of personal computing. Boasting a 16-bit architecture and a comprehensive set of instructions, it quickly gained favor for early PCs and embedded systems. This document provides a comprehensive overview of the 8086's architecture and instruction set. 8086 Architecture: The 8086 is a 16-bit microprocessor capable of processing 16 bits of data at a time. It comprises four primary components: 1. Arithmetic Logic Unit (ALU): Responsible for executing arithmetic and logical operations on data. 2. Control Unit (CU): Manages instruction execution. 3. Registers: Small, high-speed memory locations within the processor for temporary data storage. 4. Bus Interface Unit (BIU): Handles communication with external devices. Registers: The 8086 features a range of registers, including: - General-purpose registers: AX, BX, CX, DX, SI, DI, SP, BP - Segment registers: CS, DS, SS, ES - Instruction pointer (IP): Indicates the next instruction to be executed - Flag register: Stores the processor's status, including carry, zero, sign, parity, and overflow flags. Memory Addressing: The 8086 employs a segmented memory architecture, dividing memory into 64 KB segments, each identified by a segment register. The physical address of a memory location is calculated by adding the content of a segment register to the offset address. Instruction Set: The 8086 boasts a diverse instruction set that enables it to perform a wide range of tasks, categorized into several groups: - Data Transfer Instructions - Arithmetic Instructions - Logical Instructions - Control Transfer Instructions - String Instructions - I/O Instructions Addressing Modes: The 8086 supports various addressing modes, allowing it to access data in different ways, including direct addressing, register addressing, indirect addressing, indexed addressing, based addressing, and based-indexed addressing. Interrupts: The 8086 is capable of handling interrupts, which are hardware or software events that can cause the processor to pause its current execution and move to a predefined address, enabling the processor to manage external events. The 8086 microprocessor was a groundbreaking chip that significantly influenced the evolution of personal computers. Its 16-bit design, powerful instruction set, and versatile addressing modes made it a popular choice across various applications. Although newer processors have surpassed the 8086 in terms of performance and features, its impact on the computing world endures.