Tom Lenihan

Architecture Of A Single Board Computer

Defining The Components of a Computer

• What Elements Are Required?

– Electronic Integrated Circuits which are configure together to form the Hardware Architecture of the computer

– Software called the Operating System programme and makes the computer function and interact with the outside world

• Electronic Integrated Circuits– These electronic circuits (collection of transistors)

come in varying sizes, densities and functionally.– Small Scale Integration (SSI), Medium Scale

Integration (MSI), Large Scale Integration (LSI) and Very Large Scale Integration (VLSI)

– VLSI would tend to be the domain for the central core processor called a Micro Processor and typically use 250 million to 1.5 billion transistors.

The semiconductor is etched up to an resolution of 25nM ie. 0.000’000’025 of a meter

• Software

– Software is any code or programme that can run on a Computer (Micro Processor) and result in a function for that processor.

– e.g. An Operating System such as Windows 7, Unix, Sun OS, MacOS 10 etc.

– Computer Games, MicroSoft Office, iTunes etc., etc.

Computer Applications • Computer Applications where older

mechanical mechanisms have been replaced.

– Domestic Appliances: such as Microwaves, Cookers, Fridges, TV’s,…the list goes on….

– Transport: Cars, Aeroplanes, Trains etc.– Industry: Robots, Automated Production Lines,…– Communications: Mobile Phones, Satellites,… – Commercial: Cash registers, ATM, Type Writers…

In Fact every facet of modern life has been influenced by the computer.

Types of Computers• There are basically 2 types of computer

General Purpose Computer such as the standard Desktop PC, Laptop, Mainframe Computer which can run general purpose application software which is loaded up and run when required by an operator.

Micro Controller which runs dedicated software for a specific purpose such as controlling the engine of a car, the flight of an aeroplane, the cycle of a washing machine, etc….

The TomAL Target Development System

PCB (Printed Circuit Board) Overlay

Component Level Circuit Diagram

Intel 8085 Internal Diagram