History of Computers and Architecture

Flashcards for computer history and architecture

Vacuum Tubes

Digital logic elements and memory in first generation computers.

Stored Program Concept

The fundamental design approach of first generation computers.

John von Neumann

Mathematician attributed with the stored program concept.

EDVAC

First publication of the stored program concept (1945)

EDVAC

Electronic Discrete Variable Automatic Computer

IAS Computer

Prototype of all subsequent general-purpose computers.

Memory Buffer Register (MBR)

Register that contains a word to be stored in memory or sent to the I/O unit, or to receive a word from memory or I/O.

Memory Address Register (MAR)

Register that specifies the address in memory of the word to be written from or read into the MBR.

Instruction Register (IR)

Register that contains the opcode instruction being executed.

Instruction Buffer Register (IBR)

Register employed to temporarily hold the instruction from a word in memory.

Program Counter (PC)

Register that contains the address of the next instruction pair to be fetched from memory.

Accumulator (AC) and Multiplier Quotient (MQ)

Registers employed to temporarily hold operands and results of ALU operations.

Fetch Instruction

CPU fetches instruction from main memory (RAM) and stores in local registers.

Decoding Instruction

CPU needs to understand the instruction to perform it.

Executing Instruction

CPU can perform the action that is needed.

Store Instruction

Processed instruction/data is then stored after the execution cycle.

Transistor

Smaller, cheaper, dissipates less heat, solid state device made from silicon (invented at Bell Labs in 1947).

System Software

Allow the ability to load programs, move data to peripherals and perform common computations.

Discrete Component

Single, self-contained transistor manufactured separately and wired together onto circuit boards (expensive and cumbersome).

Moore's Law

Observed number of transistors on a chip doubling every year.

Gordon Moore

Co-founder of Intel, observed Moore's Law.

IBM System/360 Family Characteristics

Similar or identical instruction set, operating system, increasing speed, number of I/O ports, memory size, and cost.