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ELE22MIC - Microprocessors.

Lecturer: Paul Main.

Email: paulm@cs.latrobe.edu.au

Room: BG 441

Tel: 9018 6732

Laboratory Coordinator: Geoff Tobin.

Room: Physical Sciences 2, Room 114

Email: G.Tobin@latrobe.edu.au

Tel: 9479 3736

Course Outline:

Aims:

Develop a working knowledge of digital logic and how those principles

can be applied to implement a microprocessor system.

Learn how to design, build, program and debug a useful basic

microcomputer system.

Familiarise students to basic architecture of modern microprocessors,

micro-controllers and common peripherals.

Learn interfacing techniques for simple transducers (via the Analog to

Digital Converter) and how to apply them to implement electronic

systems.

Develop an ability to write ATMEGA128L (assembly language and C)

code to meet a design goal.

Handbook Course Description

This is a first course in microprocessors and their applications. Topics

include introduction to microprocessors, microprocessor architecture,

microcomputers, assembly language programming, memory, parallel and

serial I/O, computer design, timing, address decoding, interrupts, memory

management, caches, virtual memory, mass storage devices, DMA,

systems programming and other processors.

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Class Requirements:

Two lectures per week (total of 26)

One problem class per fortnight (total of 6 problem classes)

Three hours practical work per fortnight (total of 6 sessions).

Three assignments.

Lectures:

26 One-Hour Lectures.

Tuesday 9:00am HS1 136

Friday 9:00am PW 101

Laboratory Sessions:

One 3-Hour Laboratory Session per fortnight. - Total of 6

Labs commence next week.

Duration: 3Hours

WEDNESDAY: 2:00 pm

THURSDAY: 2:00 pm

Location: Beth Gleeson, Room 310

Problem Classes: - Total of 6

TUESDAY: 12noon, Duration: 1 Hours

WEDNESDAY: 12noon, Duration: 1 Hours

Location: HS1, ROOM 302

Consultation Times: - weekly during semester 2

Tuesday 10:00am - 12 noon PS2 Room 118

Friday 10:00am - 12 Noon PS2 Room 118

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Lecture Topics Include

Introduction to microprocessors -History & perspective

Digital Logic Review

Hexadecimal & Binary Arithmetic Review

The CPU : What's inside ?

CPU operation: Instruction Pointer, Fetch-Execute cycle, jump

Microcomputers, Microprocessor architecture,

The Arithmetic and Logic Unit - ALU

Arithmetic & Logical Instructions : Add, Subtract, Shift Left/Right

Multiply & Divide

Assembly language programming

ATMEGA128 Instruction set : Registers, Load, store, transfer, exchange,

Addressing Modes

The Condition Codes Register, Jumping, Conditional Branching,

Programming techniques and applications Flow charts

Interrupts & interrupt handlers

Memory,

Computer design -

Timing diagrams & meeting timing constraints

Address decoding,

Interrupts,

Computer memories (hardware aspect)

Computer memories (system application)

Memory management,

Virtual memory,

Mass storage devices,

Input/Output: Parallel and serial I/O, Grey codes

Serial Input/Output serial interface devices

UARTS, RS232, RS485

Simple computer networks

Designing a ATMEGA128 based computer:

memory

address space considerations

bus timing considerations

Expanded memory design & caches

The counter/timer subsystem on ATMEGA128

The A to D converter subsystem on ATMEGA128

Mass storage devices

Advanced Aspects

Caches, Direct memory access (DMA) and related issues, DMA,

Features of other micro-controllers RISC vs CISC

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Assessment:

2-hour Examination (70%),

Laboratory work (20%)

Assignments (10%).

Microprocessors Resources:

TextbooksEmbedded C Programming and the Atmel AVR

Barnett, Cox and O’Cull

ISBN 1-4018-1206-6 $96

Designing Embedded Hardware - John Catsoulis

ISBN 0-595-00362-5 $51

Web site URLs:Course Notes: http://www.sea.vg/mic

http://www.atmel.com/products/avr/overview.asp

ELE22MIC Resource CDROM

To be handed out in lecture 3.

Containing notes & device datasheets.

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Laboratory sessions cover:Familiarisation with ATMEGA128 hardware

Find out about the Bootloader monitor program,Use AVR Studio commands to view the contents of memory and processor registers.

Examine the directly addressable memory space of ATMEGA128 microprocessor andfind out how it is partitioned,

Explore various instructions and addressing modes of the ATMEGA128.

“Hello World” program.

Study the ATMEGA128's - addressing modes, - registers, - Reset vector and interrupt vectors.

This lab involves designing and writing an application program in assembler. The aimof the program is to non-destructively test an area of memory for corruption. Theproblem is to be broken up into smaller parts which are much easier to manage...

The Stepper Motor Control Lab. The timer counter subsystem.

System software development - The analog to digital (AD) converter. Applications of the AD ConverterDecoding Gray codes.

Designing, building and prototyping a useful microprocessor system.

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HISTORIC PERSPECTIVE - TIMELINE OF COMPUTING

The Abacus “Computing Tray” The first mechanical calculating machine. 28?

The Computing Tray - was used by Babylonian priests to keep track of their

vast storehouses of grain. Still in use today. Circa 3000BC.

In Roman times the board was given grooves to facilitate moving the counters

in the proper files.

Circa 1300BC Wire & Bead Abacus replaced the Chinese calculating rods.

A modern equivalent is an Accumulator it is used to accumulate intermediate

results of arithmetic calculations. Modern accumulator uses binary numbers.

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Analog Calculators:

In 1612 John Napier uses the printed decimal point, devised logarithms and

used numbered sticks (or Napiers Bones) for calculating.

This principle lead to the invention of the slide rule.

Mechanical Calculators

In 1642: Blaise Pascal Invented the first mechanical calculator constructed of

10-toothed gears, wheels & teeth. It was

called “Pascalene”.

The same principle is still in use in

automobile’s (mechanical) odometer

mechanism. The same principle was the

basis for all mechanical calculators.

Punched Cards

In 1801 Joseph Marie Jacquard invented a

machine to use a linked sequence of

punched cards programmed to control a

weaving machine and produce intricate

weaving patterns in cloth.

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1823: The royal Astronomical Society of Great

Britain commissioned Charles Babbage to

produce a programmable calculating machine. He

was aided by Augusta Ada Byron, the countess

of Lovelace - the first programmer. The machine

was to produce navigational tables for the Royal

Navy.

1834 Babbage shifted his focus to work on The

Analytical Engine. The mechanical computer

stored 1000 20-digit decimal numbers and a

variable program that could modify the function

of the machine to perform various tasks.

Input to his engine was through punched cards. It is assumed that he obtained

the idea from Frenchman, Joseph Jaquard.

After many years of work, Babage’s dream faded when he realised that the

machinists of the day were unable to create the parts needed to complete his

work. The analytical engine required 50 000 precision machined parts to allow

his engine to function reliably.

Michael Faraday

Was the son of a blacksmith. He had limited formal education but

attended public lectures and became an avid reader. In 1813 Started

working life at the London Royal Institution as a laboratory assistant. In

1821 demonstrated the electric motor effect. In 1831 demonstrated

EMF(current) induced by motion of magnet by a nearby conductor.

Electric Motors became available.

Motor driven adding machines based on mechanical calculators

developed by Blaise Pascal became popular. Electrically driven

mechanical calculators were common office equipment until 1970s.

Telecommunication by Morse Code

1844 - Samuel Morse sent a telegraph from Washington to Baltimore.

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George BoolePublishes “Laws of Thought”, describing a system for symbolic & logical

reasoning which becomes the basis for computer design.

1858 A telegraph cable spans the Atlantic Ocean & provides service for a few

days.

Alexander Graham Bellin 1876, invents and patents the telephone.

Herman Hollerith’s Tabulator

In 1889, Herman Hollerith developed punched cards for storing data.

Like babbage he also borrowed the idea of a punched card from Joseph

Jaquard. Hollerith developed a machine that counted, sorted and collated

information stored on punched cards. He founded the Tabulating Machine

Company. After a number of mergers, the Tabulating Machine Company

was formed into the International Business Machines Corporation - IBM.

The punched cards used in computer systems are often

called Hollerith cards.

The 12-Bit code used on a punched card is called the

Hollerith Code. Mechanical machines continued to

dominate the Information Processing world until

1941.

Guglielmo MarconiIn 1895, transmitted the first radio signal.

Claude Shannon in 1937 publishes the principles for an electric adder using base two.

Conrad ZuseGerman Inventor, created the first

electro-mechanical calculating computer in 1941.

It was used for aircraft & missile design during

World War II for the German war effort.

The Z3 used a 5.33Hertz clocking frequency and

was based on electro-mechanical relays.

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World War II (WWII) commenced.

Great Britain’s survival depended on imports of fuel, food, weapons &

industrial raw materials. Germany’s Gossadmiral Doenitz’s planned to

sink the merchant ships that were bringing supplies to Brittain by using a

powerful submarine fleet. Doenitz calculated that sinking 800 000 tons of

merchant ships per month would bring Britain to starvation, surrender

and a request for peace would result.

Enigma:

1941 German Commands to the submarine fleet were initially encrypted

with a three rotor Enigma before being transmitted by radio to submarine

commanders.

Enigma is Greek for ‘puzzle’. An example of how it works:For example the letters ‘e’ input might be connected to the first rotor’s ‘q’ output. Soan arriving ‘e’ pulse in the first rotor goes as ‘q’ to the second rotor where it mightdepart as ‘g’ to the third rotor. When a key is pressed, the right hand motor advancesone notch, changing the encryption sequence.

After 26 advances, the next rotor is advanced, etc. Also Enigma had a plug board with26 sockets, each with up to 10 holes interlinked by the operator’s choice ofconnections. Enigma also had many extra rotors with different internal connections.The configuration of rotors and plug-board was changed daily.

Enigma Code Breaking:

Capturing a 1940 Kurzchussel cipher from the weather ship, Muenchen,

enabled British code breakers at Bletchey Park to decrypt the messages

with the aid of a crude “Bombe” computer - A computer to decipher the

Enigma encryption machine settings for that day.

Four Rotor Enigma

In Feb 1 1942 Germans began encrypted communication with a four rotor

Enigma. British crypt-analysts were unable to decrypt these new

messages.

The cost of failure to decrypt Enigma messages:

1942 Jan-July 460 ships, 203000tons, sunk.

Jan 1943 29 ships per month

March 1943 the rate had increased to 95 ships per month totalling

627000tons - twice the rate of new-ship construction.

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Capturing Enigma:

Oct 30, 1942: a 25-pound four-rotor Enigma machine, with short signal

code-book, was recovered from a sinking German submarine, U559, by

two sailors who swam into the submarine from the destroyer Petard. The

two sailors lost their lives as the submarine plunged to the bottom of the

sea.

The First Electronic Computer

June 1943: Alan Turing, Tommy Flowers & MHA Newman made

operational the first electronic computer, Colossus. Colossus was utilised

to break the cipher codes generated by the mechanical Enigma Machine;

German military communication security was compromised.

RadarBritish centimeter wavelength radar assisted to provide British military

superiority.German submarine attacks ceased being a threat for the

remainder of WWII.

ENIAC1945: The University of Pennsylvania created ENIAC, the Electronic

Numerical Integrator And Calculator.

Weight: 30 ton

Used 17 000 vacuum tubes

500 miles of wires.

ENIAC was re-programmed by rewiring, a process that took many

workers several days.ENIAC was programmed by electrical connections

on plug-boards that looked like early telephone switchboards.

ENIAC processed 100 000 Instructions Per Second.ENIAC suffered reliability problems due to limited vacuum tube life.

William Shockley1939 William Shockley observed P- and N- type regions in Silicon.

Shockley forecast that a semiconductor amplifier was possible, but WWII

interrupted further work.

John von Neumann1945: John von Neumann described the principles for a general-purpose,

stored program computer.

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William Shockley, John Bardeen & Walter Brittain

1948: The invention of the Germanium bipolar junction transistor at Bell Labs,

by William Shockley, John Bardeen & Walter Brittain

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Texas Instruments (TI) commercialised the Transistor.

The First IC.

At Texas Instruments, Jack Kilby, In 1958

realised that

1. Resistors could be formed by cutting small bars of silicon,

2. Capacitors formed by wafers metalised on both sides, and

3. Silicon transistors could all be made on the same material.

In september 1958 he created a phase-shift oscillator - the first IC on one wafer.

1964: The first mass produced mini-computer was produced by Digital

Equipment Corporation - The Digital Equipment Corporation (DEC) PDP8

mini-computer

Robert Noyce & Gordon Moore - founders of Fairchild Semiconductor -

became disgruntled and left Fairchild Semiconductor to start N M Electronics.

Bob Noyce wrote a single page business plan on his typewriter one night.

Noyce went to see Fairchild’s Venture Capitalist Art Rock. He requested

$2.5Million Dollars as venture capital...which he received 2 Days Later and

Intel was founded on 18 July 1968 by Robert Noyce, Andy Grove & Gordon

Moore. Intel’s first product was the ‘3101’, a 64 Bit Schottky Barrier static

RAM.

Busicom, was Japanese calculator manufacturer, and wanted Intel to develop 12

custom chips for their calculators.

Ted Hoff, an engineer at Intel, recommended one chip to function as 12.

Busicom agreed & contracted Intel. Intel went ahead with a general purpose

logic chip capable of being programmed for instructions. First use of

‘Intelligence’ programmed by software. Intel bought the design (Intellectual

Porperty) back from Busicom.

The Intel 4004. After 9 months development Intel’s first microprocessor is born, the

4004.

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The Intel 4004.

First MicroProcessor.

November 1971

10 Micron technology

2300 Transistors

108 KKz Clock

60 000 Instructions/second

Bus width 4 bits

640 bytes addressable

12 Volt. Weighed < 1 Oz.

P-channel MOSFET

Applications: Busicom Calculator

The Intel 8008

April 1972

10 Micron technology

3500 Transistors

200 KKz Clock

0.06 Million Instructions Per Second (MIPS)

Bus width 8 bits

12 Volt

Address: 16 Kbytes

Apps: Terminals, Calculators, Bottling

Machines

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The Intel 8080

April 1974

6 Micron Technology

4 500 transistors

2 MHz Clock

0.64 Million Instructions Per Second

Data Bus width: 8 bits

12 Volt

Addressable memory: 64 KbytesApps: Traffic light controller,

Used in the Altair computer

(first PC)

Performance = 10 x 8008

Over six times the performance of ENIAC

Intel 8086/8088

June 1978/1979

3 Micron Technology

5, 8 &10 MHz clock

0.33, 0.66 & 0.75 MIPS

29 000 Transistors

16/8 bit data bus

20 bit address bus (1MB)

5 Volt

apps: IBM PCs & Clones

performance =10 x 8080

Segmented architecture,

Complex Instruction Set Computer.

(CISC. )

8087 external Maths Coprocessor

available.Select instructions compatible with 8080 & 8085.

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1981 The open-architecture IBM PC is launched based on the Intel 8088

1980 PCDOS sold to IBM

1980 Ada emerged

1980 dBaseII popular

1982 First Clone PC

1982 AutoCAD

1983 TCP/IP invented

1982 Original NMOS 80186

Intel 80286

February 1982

6 MHz -12 MHz clock

0.9 - 2.66 MIPS

1.5 micron technology

134 000 Transistors

16 bit data bus

16MB Physical, 1GB Virtual

Performance =3 to 6 x 8086Software Backward Compatible with

8086

Competitors parts: NecV.20, AMD 286 &

Cyrix 286

Intel 80386

October 17, 1985

16 MHz - 33MHz

5 to 11 MIPS

1 Micron technology

275 000 Transistors

Data Bus width: 32 bits

Addressable memory: 4 GigaBytes (GB)

Virtual memory: 64 TeraBytes (TB)Software Compatible with 8086 & 80286

New 32 bit “Flat Mode” available.

Performance =100 x Intel 4004

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1987 80C186 converted to CMOS - uses 1/4 power at twice clock rate

Many popular peripherals included on-chip:

Oscillator, Timers, UARTs, DMA, DRAM controller etcUsed in Controllers, Security Systems, Terminals

Segmented architecture

Software Backward Compatible with 8086

Still popular

The Intel 80486

April 1989 - Intel 80486

25 MHz, 20 MIPS

June 1991 50 MHz, 41 MIPS

1.2 Million Transistors

1-0.8 Micron Technology

Bus width: 32 bitsAddressable memory: 4 GB

Virtual memory: 64 TB

50X performance of the 8086.Software Compatible with 8086

486DX first CPU to include floating

point maths co-processor on-chip.

Intel Pentium

March 1993

60 MHz 100 MIPS

66 MHz 112 MIPS

3.1 million transistors

0.8 Micron technology

64-bit external data bus

32-bitmicroprocessor

32 bit address bus4 GB physical64 TeraBytes ( TB) virtual

Software Compatible with8086/286/386/486.

BiCMOS

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Intel Pentium Pro

November 1995

150-200 MHz

5.5 million transistors

0.35 micron technology

64 bits front side bus64 bits to L2 cache

Addressable memory: 64 GBVirtual memory: 64 TB

256K - 1MB L2 CacheSoftware Compatible with 8086

Intel® Xeon™

Designed for dual- and multi-processor computers.

These dual processor workstations are expected toachieve between 30 to

90 percent performance increase over systems using Intel® Pentium® III

processors.

The Intel Itanium™

Revolutionary design 64-bit products

Explicitly Parallel Instruction Computing (EPIC) design technology.

2002: Itanium™ 2

The Intel® Pentium® M - 2003.

The Intel® Pentium® M (Mobile) processor, the Intel® 855 chipset

family, and the Intel® PRO/Wireless 2100 network connection are the

three components of Intel® Centrino™ mobile technology.

It enables extended battery life and thinner, lighter mobile computers

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Figure 18 - Athlon XP interface diagram

The main competition for Intel is AMD.

AMD compete on price and performance.

AMD chips typically have higher performance per dollar.

However, Intel has been the clear leader in the dual/multi-cpu market with

experience dating back to the early 1980s with their 8086/8088.

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Low Power Embedded Processors:

1991: 80186EC

Includes 22 peripherals on one chip including: Power-save clock divider,

PowerDown Idle, 80C187 interface, 8259 compatible Programmable

Interrupt Controller, Timer-counter unit, enhanced chip select unit, 4

channel DMA unit, Serial Communications unit, DRAM Refresh Control

Unit, Watchdog Timer Unit.

Motorola 68HC11 Microcontroller

Primarily used in applications performing a single task or single group of tasks,

controlling:

Microwave Ovens

Fridges

Toasters

Automobiles

In 1991, > 750 million 8-bit microcontrollers were delivered by chip

manufacturers

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Figure 19 - Motorola 68HC11A8 Microcontroller Block Diagram

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Figure 20 - ATMEGA128 - Block Diagram - From the AVR manual Page 3.

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DIGITAL LOGIC REVISION

5V Standard Logic Levels:

Logic High, 1, or True

TTL family level > 2 Volts (greater than 2V)

CMOS , > 2/3 VCC (> 3.33V for VCC=5V)

Logic Low, 0, or False

TTL level < 0.8 Volts (less than 0.8V)

CMOS, < 1/3 VCC (< 1.66V for VCC=5V)

TTL logic level compatible families include: 74xx (plain ttl),

F (fast), S (Schottky), LS (Low Power Schottky), HCT (High speed CMOS Ttl

compatible), ABT (Advanced Bipolar Ttl compatible)

CMOS Compatible: 4000 series, 74C (CMOS) 74HC (High Speed CMOS),

74 Series logic is designed for 5 Volt Power Supply.

The 4000 series logic is designed for 3-15 Volt power supply.

CMOS is considered to be the Ideal Logic Family because it has near zero static

power dissipation. The input equivalent circuit of a CMOS transistor is a 1012

Ohm (1 Tera Ohm) resistor shunted by a 5pF or less capacitor.

Most CMOS inputs also contain diodes connected to power supply rails to

protect from overvoltage and undervoltage whilst in circuit (but out of circuit the

supply rails wont clamp over/under voltages).

Most modern microprocessors are fabricated using CMOS technology.

CMOS Power dissipation

Power Dissipation in CMOS chips arises from mainly from the following

sources:

1. Current pulses that occur when both FETs are switched on - typically during

the transition period of a logic level change (I.e. High -> Low or Low -> High

transition).

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Figure 22 - Charging parasitic capacitance Figure 23 Discharging parasitic capacitance

2. Resistive power dissipation in the FET’s Source-Drain path due to charging

the capacitance on outputs. So lowering capacitance has a direct effect on

lowering power dissipation. Power dissipation is proportional to CV2f, where C

is total Capacitance switching, V is supply Voltage, f is switching frequency.

3. Resistive power dissipation in the load and the FET’s Source-Drain path due

to resistive loads placed on outputs - V2/R power dissipation.

4. Supply voltage variation. The greater supply voltage, the greater the CV2f and

V2/R power dissipation.

When CMOS chips are not switching (static operation), the main power

dissipation will be from items 3 and 4 above.

At high frequencies we can see that power dissipation rises proportionately with

switching frequency - refer item 1 and 2 above.

Both these sources of power dissipation necessitate the use of power supply

decoupling capacitors located adjacent (within 1 cm) to each chip. The

decoupling Capacitor supplies power for

1. Charge pumping into the bus and

2. the current pulse through the Complementary FET switches

(Sometimes power supply decoupling capacitors are referred to as power supply

bypass capacitors, )

To minimise power consumption in a system, the circuit should be run at

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the lowest acceptable speed to get the job done. This is also good practice from

the perspective of achieving C-Tick approval as the lower the clock rate, the

lower the frequency of radiation, and the simpler the noise suppression

techniques required to gain C-Tick approval. At higher frequencies RF noise

radiates readily from short Printed Circuit Board (PCB) tracks.

Floating Inputs

Due to the exceptionally high input impedance any CMOS input left

disconnected, the input will drift back and forth between logic 1 and logic 0 -

floating. The floating inputs will cause unpredictable and unreliable outputs and

possibly result in some intriguing, insidious or unexplainable system bugs. The

parasitic capacitance of a clock signal wire passing near a floating input could

make the device dissipate more power at best, and cause the chip to self-destruct

at worst.

Not only will the logic functions be unreliable, but a floating input is more

susceptible to problems known as Zap and Latch-Up. ****

Unused inputs should always be connected to a valid logic level,

preferably by a 10k ohm resistor. In the event that you decide to use that input, a

jumper-wire connection can replace the resistor connection.References:

1. IEEE Timeline of computing History -

by Bob Carlson, Angela Burgess, and Christine Miller.

2. http://www.intel.com/intel/intelis/museum/online/hist_micro/hof/index.htm

3. MC68HC11A8 - “The Motorola HCMOS Single-Chip Microcontroller” TECHNICAL DATA,

11a8td.pdf

4. ATMEL AVR ATMEGA128L Datasheet:http://www.atmel.com/dyn/resources/prod_documents/doc2467.pdf

5. “Microelectronic Circuits”, Fourth Edition Sedra/Smith.

Schematic Drawings created by Paul Main using Protel Altium6, DXP or Protel.