CH04

Objectives / Learning Goals

• Know parts of a modern computer system.

• Understand how components work together to run programs.

• Learn basic computer structure and its relation to programs.

Week 4 Overview

Class Introduction and Focus

• Transition from introduction phase to core content of the course.

• Focus on "Marie" as a foundational example of computer architecture.

Upcoming Topics

• Instruction Set Architecture (ISA) in Chapter 5.

• Emphasis on Intel instruction set; be sure to review material ahead of time for better comprehension.

Homework Review Ch03

Key Concepts:

• Boolean Operations:

  • Product (AND): True only when all operands are true.

  • Sum (OR): True if at least one operand is true.

• Ripple Carry Adder:

  • A series of full adders configured in sequence with carry-outs feeding into the next.

Circuits:

• Combinational Circuits:

  • Outputs depend solely on current inputs.

• Sequential Circuits:

  • Outputs are influenced by both current inputs and previous states.

Edge-Triggered vs. Level-Triggered:

• Edge-Triggered: Changes occur at distinct moments during clock signal transitions.

• Level-Triggered: Changes can happen whenever the clock is in a specific state.

Flip-Flops:

• D Flip-Flop: Represents memory for a single bit of information.

Truth Tables and Logic Expressions:

• Example: Truth table illustrating AND operation being true when all inputs are true.

D. Morgan's Law:

• Explains the relationship between conjunction and disjunction in Boolean algebra.

Project Discussion

• Major project: Create a basic integer calculator using "Marie" architecture.

  • Features: Supports number/operator input, looping on invalid inputs, and handling negative multipliers.

  • Optional extra credit involves including division functionality.

Introduction to Marie Computer

Architecture Basics:

• Uses binary two's complement for integer representation.

• Memory size: 16 bits, 4K words available.

Registers:

• Accumulator (AC): Holds intermediate arithmetic and logic results.

• Memory Address Register (MAR): Contains addresses for memory operations.

• Memory Buffer Register (MBR): Temporarily stores data transfers.

• Program Counter (PC): Monitors the address of the currently executing instruction.

• Input/Output Register: Facilitates data exchange with peripheral devices.

Instruction Set Architecture (ISA) in Marie:

• Contains 13 distinct instructions: Load, Store, Add, Subtract, Input, Output, Halt, Skip, Conditional, Jump.

Fetch-Decode-Execute Cycle:

1. Fetch: Read an instruction from memory into the instruction register.

2. Decode: Interpret the instruction to prepare necessary components for execution.

3. Execute: Perform the instruction, potentially updating memory and registers.

Indirect Addressing in Marie:

• New instructions introduced for enhanced data manipulation.

Introduction to C Programming

• Call by Value: Changes do not alter the original variable.

• Call by Reference: Directly modifies the original variable.

Breakout Groups

• Discussions focused on enhancing project development and fostering collaboration strategies.

Important Concepts Covered

• General overview of computer systems.

• Major components of digital circuits.

• CPU basics: Functions, components, and bus structure.

Upcoming Topics

• Introduction to new CPU architectures (e.g., Intel vs. MIPS).

• Preparation for the midterm exam covering Chapters 1-5.