131 Week 1 - Computer Architecture Flashcards
Computer
An electronic device for storing and processing data, typically in binary form, according to instructions given to it in a variable program.
Analytical Engine
First computer. It was a fully programmable mechanical computer
Built by Charles Babbage 19th Cent.
Made up of the mill (calculating unit), the store, the reader, and the printer.
Data inputted through punch cards.
ENIAC (Electronic Numerical Integrator And Computer)
First programmable, electronic, general-purpose digital computer.
Programmed via switches and cables.
Able to solve a large class of numerical problems through reprogramming.
Manchester SSEM (Small-Scale Experimental Machine)
First electronic stored program.
Successfully ran its first program on the 21st June 1948.
Cambridge EDSAC (Electronic Delay Storage Automatic Calculator)
First practical stored-program computer in regular use.
Used punch cards to load programs.
Ran its first programs in 1949.
IBM Personal Computer
First personal computer
Led to an era of cheap commodity based computation
Computer Architecture
Set of rules and methods that describe the functionality, organization, and implementation of computer systems.
Von Neumann Architecture
A type of architecture that includes:
Memory that stores data and instructions.
A control unit that contains an instruction register and program counter.
A processing unit that contains an arithmetic logic unit (ALU) and processor registers.
Input and output mechanisms
CPU
Central Processing Unit
Contains Arithmetic Logic Unit (ALU), Control Unit (CU), Cache
Harvard Architecture
Instruction and data memories stored separately - cannot modify instruction memory at run time
Parallel access to instructions and data - can be faster
Not suited to self-modifying code
Modified Harvard Architecture
Separates instruction and data cache internally
Single unified main memory still visible to users/programmers
Looks like Von Neumann from users/programs view
What factors measure computer speed
Clock rate, Millions of instructions per second (MIPS), floating point operations per second (FLOPS)
How does density limitations limit speed?
Transistor density affects how computer speed, the more transistors per square inch, the higher the speed.
More recently it has been getting harder to make components smaller than they already are.
Moore’s Law
The speed and capability of computers can be expected to double every two years, as a result of increases in the number of transistors a microchip can contain.
How does heat limit speed?
Heat build-up from transistors can cause reductions in performance. Cooling needs to be able to match the amount of heat produced to stop overheating.
