CS316 – Architecture and Organization: Digital Logic

Vocabulary flashcards covering Computer Architecture history, generations of computing, combinational circuits (half and full adders), and various types of flip-flops.

Computer Architecture

The field of study of selecting and interconnecting hardware components to create computers that satisfy functional performance and cost goals

Computer architecture

it refers to attributes visible to a programmer that have a direct effect on program execution.

Computer Architecture

concerns Machine Organization,
interfaces, application, technology, measurement & simulation

instruction set, data format, principle of operations, features

the four characreristics of computer architecture

ENIAC

Designed by Mauchly & Echert and built by the US Army in 1945 during world war II to calculate trajectories for ballistic shells using around $18000$ vacuum tubes and $1500$ relays.

ENIAC

programmed to manually setting switches

UNIVAC

The first commercial computer invented in 1950

John Von Neumann Architecture

An architecture developed from the idea of ENIAC that stores programs in memory; features include a single read-write memory, addressable locations, and sequential execution.

Goldstein and Von neumann

developed an architecture using the idea of ENIAC to developed concept of storing a program in the memory

First Generation (1940-1950)

The era of computer history characterized by the use of Vacuum Tubes and machines like ENIAC and UNIVAC.

Second Generation (1950-1964)

The era of computer history characterized by the invention of the transistor, the first operating system, high-level languages, and floating point arithmetic.

Third Generation (1964-1974)

The era characterized by the use of Integrated Circuits (IC), microprocessor chips, semiconductor memory, and a drastic reduction in computer size.

Fourth Generation (1974-Present)

The era defined by Very Large-Scale Integration (VLSI) and Ultra Large Scale Integration (ULSI), combining millions of transistors on a single-chip processor.

Combinational Circuit

A circuit comprising logic gates whose outputs at any time are determined directly from the present combination of inputs without regard to previous inputs.

Half-Adder

A combinational circuit that performs the addition of two bits using two binary inputs ($x$ and $y$) and producing two outputs: Sum ($S$) and Carry ($C$).

Full-Adder

A combinational circuit that performs the addition of three bits: two significant bits ($x$ and $y$) and a previous carry ($z$).

Half-Adder Sum of Products (SOP) Expressions

The logical relationship expressed as $S = x'y + xy'$ and $C = xy$.

Flip-Flop

An application of logic gates that can remain in a binary state indefinitely (as long as power is delivered) until directed by an input signal to switch states.

S-R Flip-Flop

A SET-RESET flip-flop consisting of two NOR gates and two NAND gates.

Clocked S-R Flip-Flop

A flip-flop modified with an additional control input (clock pulse) that determines when the state of the circuit is to be changed.

D Flip-Flop

A modification of the clocked S-R flip-flop where a CP value of $1$ (HIGH) moves the flip-flop to the SET state and a value of $0$ (LOW) moves it to the CLEAR state.

J-K Flip-Flop

A modification of the S-R flip-flop where the intermediate state is more refined and precise.

T Flip-Flop

A much simpler version of the J-K flip-flop.