COMS W1004 Lecture Notes - Lecture 12: Instruction Register, Program Counter, Von Neumann Architecture

• School: Columbia University
• Department: Computer Science
• Course: COMS W1004
• Professor: Adam Cannon

Document Summary

Java- lecture 12, 2/25/16: computer organization, von neumann architecture. Input/output: memory, alu (arithmetic/logic unit, control unit, ability to have a stored program. A stored program is a sequence of machine language instructions stored as binary values in the memory: the control unit. Fetches from memory the next instruction in the program to be executed: decodes the instruction in order to figure out what is to be done next. Executes it by issuing the appropriate command to the alu memory and i/o controllers. The control unit will read in a program and follow every command until it reads the last command in the sequence: machine language. The instructions that the control unit interprets is represented in machine language, which is typically expressed in binary: an instruction is made of two parts. The operation code is a unique unsigned integer value that is used to represent a machine language operation.