0

A physical model for playing the ages old Indian game CHIDIYA UDD

EC-316 MICROPROCESSORS LAB ELECTRONICS AND COMMUNICATION DEPARTMENT

NETAJI SUBHAS INSTITUTE OF TECHNOLOGY DELHI UNIVERSITY

MAHIMA SINGH 93/ec/13 &

MANISHA GAHLOT 97/EC/13 3 JUNE 2016

1 | P a g e

ACKNOWLEDGEMENT With profound respect and gratitude we take the opportunity to

convey our sincere thanks to Prof. D.V. Gadre for introducing us to

such practicality of the subject and providing valuable guidance and

resourses leading to the accomplishment of the project titled as “8085

CHIDIYA UDD” based on 8085 Microproccessor.

Special thanks to our seniors and peers in CEDT for their constant

support and guidance.We would also like to thank the various lab

assisstants who patiently helped us during the course of the project

work.

We would also like to thank www.pcbpower.com for precise

manufacture and timely delievery of the project board.

2 | P a g e

TABLE OF CONTENTS

1. INTRODUCTION

2. ACKNOWLEDGEMENT

3. JUSTIFICATION & MOTIVATION

4. MATERIALS REQUIRED

5. PROJECT DESCRIPTION

6. A LOOK INTO THE SCHEMATIC

7. A LOOK INTO THE BOARD LAYOUT

8. MAIN BLOCK DIAGRAM

9. THE 8085

10. THE 8255

11. THE 8085

12. RAM AND ROM

13. DECODING CIRCUIT

14. THE CODE

15. TESTING THE BOARD

16. PROBLEMS FACED

17. GANTT CHART REVISITED

18. CONCLUSION

19. BIBLIOGRAPHY

3 | P a g e

INTRODUCTION 8085 CHIDIA UDD is a physical structure to play the ages old chidiya

udd game using 8085 which otherwise has no physical structure

available for it.The game basically consists of a LCD onto which the

names of objects would be displayed randomly and 2 switches

corresponding to 2 players who after seeing the displayed objects

name would make a quick decision whether the object flies or not .if

the object flies players release the switches and keep them pressed if it

doesn’t fly.the system would analayze the right and wrong moves and

accordingly display the score.The player with more score would be the

winner in the end.

MOTIVATION AND JUSTIFICATION As already known, ‘Chidiya Udd’ has been one of the most famous

games amongst kids. However there is currently no physical structure

available in the market which makes it possible to play this game. We

aim to create such a structure using the 8085 microprocessor. It shall

cater to entertainment and recreational needs as well as provides a

perfect example of simulating Indian traditions using technology.This is

what motivated dus to go about making this 8085 based challenging

project.

4 | P a g e

MATERIAL REQUIRED

S NO.

NAME OF COMPONENT

1. RESISTORS

2. CAPACITORS

3. 8085

4. 8255

5. LATCHES- 74573N

6. DECODER-74138N

7. PUSH BUTTONS

8. 32K EEPROM

9. 32K RAM

10. RED LEDS

11. 16 * 2 LIQUID CRYSTAL DISPLAY

12. EEPROM PROGRAMMER

13. 10K POT

14. NOR GATE 7402

15. BERG STRIP

16. LC CRYSTAL 6MHZ

17. POWER CONNECTOR

5 | P a g e

A LOOK INTO THE SCHEMATIC

A LOOK INTO THE BOARD LAYOUT

This was the board obtained after making the schematic. The

board was routed after this keeping in view all the standard

measurement and sizes. The gebers were sent to pcb power

for final manufacture of our chidiya udd board

1 | P a g e

The project heart lies in the microprocessor 8085 which controls the logic , the peripherals and the memory. As the project doesn’t involve any interrupt logic the interrupt pins have been pulled down . A switch is connected to the SID pin which was used to test the microprocessor using SID SOD test. The address lines latched are connected to various points such as chip select of RAM, ROM, and 8255. A 32K RAM and 32K ROM has been used for the memory. 8255 has been used to interface the input switches on PORT A and LCD data lines on PORT B. 8255 is therefore used in MODE 0 I/O. PORT C lower pins are used for control pins of LCD.A micro USB connector has been used to power the board. A crystal of 6MHZ has been used as a clock. On powering the board the LCD shows chidiya udd.The game can be

played at a time by 2 players. The project comprises of a LCD screen

and 2 push buttons. One push button would be made available to 1

player.The LCD screens would show the name of the creature/object

under test and would simultaneously display the score.So now in the

beginning CHIDIYA UDD would be displayed on the screen, thereafter

we begin with our game .pressing of the push button indicates a not

flying action whereas release of the push button indicates a flying

action. So what basically needs to be done by the player is that when

a player sees the name of the creature/object on the screen , he

decides whether that object flies or not . if according to him it flies

he releases the button nd if it doesn’t fly he keeps the button

pressed. Now this display of names occurs randomly and every name

is displayed after 2 seconds. So the player effectively gets 2 sec to

judge that he should fly or not. The input given by the player on the

push buttons is analysed by the microprocessor and accordingly his

2 | P a g e

score is incremented by one if he makes a correct move . The person with the higher cumulative score in the end would win. A block diagram has been included for further reference.

3 | P a g e

BASIC BLOCK DIAGRAM

.

MIC

RO

PR

OC

ESSO

R

MEMORY

INP

UT

FRO

M P

USH

BU

TTO

NS

OU

TPU

T TO

LC

D D

ISP

LAY

THE 8085

8085 is an 8 bit microprocessor introduced by intel in 1976. This 40

pin IC is an update over the microprocessor 8080 and requires less

support circuitry, allowing simpler and less expensive microcomputer

systems to be built. It uses a multiplexed addess/data bus which

reduced the number of PCB tracks to memory segments.

While it has the conventional von Neumann design based . on 8080,

it still extends to incorporate 3 maskable vectored interrupts (RST 7.5

, 6.5 , 5.5) , a non vectored interrupt INTR. All the interrupts are

enabled using the instruction EI and disabled using DI. INTA is used

to send an acknowledgement to the device which requested an

interrupt.

It can accommodate slower peripherals using the READY pin

through externally generated wait states. It can drive itself using

the crystal

1 | P a g e

externally connected to X1 and X2, while a internal clock generation

uses a divide by two circuitry.

Although it does not require demultiplexing of address line to

generate the lower byte of the address, which can be done using a

latch whose enable pin is connected to ALE pin of the 8085. ALE pin

goes high at the start of every machine cycle, which enables the

addresss latch.

Read control signal which is active low indicates that the selected I/O

or memory device is to be read and data are available on the data

bus. Write control signal which is active low indicates that the data

on the data bus are to be written into a selected memory or i/o port.

IO/M* is a status signal used to differenciate between I/O and

memory operations. When it is low it indicates a memory operation

and when high it indicates a I/O operation. The signal is combined

with RD* and WR* to generate input output and memory signals. S1

& S0 are status signals.

HLDA signal acknowledges a hold request. HOLD signal indicates that

a external peripheral such as a DMA controller is requesting the use

of address and data bus.READY is used to delay the microprocessor

read or write cycles to synchronise a slow peripheral with the 8085.

RESET IN * when the signal on this pin goes low, the program

counter is set to zero and the buses are tristated and the MPU is

reset. RESET OUT signal indicates that the MPU is being reset. The

signal can be used to reset other devices.

PCB LAYOUT

1 | P a g e

SOLDERED PCB BOARD

2 | P a g e

SOLDERED BOARD

3 | P a g e

FINAL WORKING BOARD

THE 8255 The 8255 has 24 input/output pins in all.[5] These are divided into three 8-bit ports (Port A, Port B, Port C).[6] Port A and port B can be used as 8-bit input/output ports. Port C can be used as an 8-bit input/output port or as two 4-bit input/output ports or to produce handshake signals for ports A and B.

The three ports are further grouped as follows:

1. Group A consisting of port A and upper part of port C.

2. Group B consisting of port B and lower part of port C.

Eight data lines (D0 - D7) are available (with an 8-bit data buffer) to read/write data into the ports or control register under the status of the RD (pin 5) and WR (pin 36), which are active low signals for read and write operations respectively. The address lines A1 and A0allow to successively access any one of the ports or the control register as listed below:

A1 A0 Port selected

0 0 port A

0 1 port B

1 0 port C

1 1 control register

The control signal chip select CS (pin 6) is used to enable the 8255 chip. It is an active low signal, i.e., when CS = '0', the 8255 is enabled. The RESET input (pin 35) is connected to the RESET line of system like

1 | P a g e

8085, 8086, etc., so that when the system is reset, all the ports are initialized as input lines. This is done to prevent 8255 and/or any peripheral connected to it, from being destroyed due to mismatch of ports. As an example, consider an input device connected to 8255 at port A. If from the previous operation, port A is initialized as an output port and if 8255 is not reset before using the current configuration, then there is a possibility of damage of either the input device connected or 8255 or both since both 8255 and the device connected will be sending out data.

The control register or the control logic or the command word register is an 8-bit register used to select the modes of operation and input/output designation of the ports.

We use 8255 in mode 0.

Mode 0 - simple I/O

In this mode, the ports can be used for simple I/O operations without handshaking signals. Port A, port B provide simple I/O operation. The two halves of port C can be either used together as an additional 8-bit port, or they can be used as individual 4-bit ports. Since the two halves of port C are independent, they may be used such that one-half is initialized as an input port while the other half is initialized as an output port.

The input/output features in mode 0 are as follows:

1. Output ports are latched.

2. Input ports are buffered, not latched.

3. Ports do not have handshake or interrupt capability.

4. With 4 ports, 16 different combinations of I/O are possible.

THE RAM AND ROM

RAM or Random Access Memory is used basically to store data

while running the program. We can both read and write data into

it. This memory is volatile. When the power is turned off, all its

contents are destroyed.

ROM or Read Only Memory is the main memory of the brain

8085. 8085 fetches instructions saved sequentially in the ROM.

Saved on the ROM is the entire program that the 8085 has to

execute. We can only read from the ROM once it is connected to

the board.We have used EEPROM which is Electrically Erasable

Programmable Read Only Memory, since the information stored

in this memory can be altered using electrical signals. Unlike RAM

its contents do not get destroyed when power is turned off and to

write data into it we need an EEPROM programmer.

RAM and ROM come in various sizes. We have chosen 32K ROM

and 32K RAM. Our work could have been easily accomplished by

8K ROM and 8K RAM but to be on the safe side we took a larger

memory. A larger memory leads to slight variations only in the

interfacing circuitry rest of the connections remain the same.

THE DECODING CIRCUIT

The decoding circuit is basically used to enable the RAM,ROMand

the I/O devices at the right time.

A decoder identifies each combination at its input and decoded it

into its binary equivalent. It commonly used in interfacing I/O

peripherals and memory. Decoders are also in built in memory

chip to select specific registers in it.

In our project we have used 3x8 decoder(in-order to

accommodate any future change as wells).

Address lines A15, A14 and,A13 have been used as input to

decoder 74138

A1

5

A1

4

A1

3

LOGIC

0 0 0 ROM ENABLE

0 1 0 RAM ENABLE

1 0 0 LED ROW ENABLE

1 0 1 LED COLUMN ENABLE

The decoder circuit can be replaced by use of logic gates.

THE CODE

.ORG 0000H

LXI SP,0000H ;STACK POINTER INITIALISATION

MVI A, 00H

LXI H, 8000H

MOV M, A ;initial score for P1

INX H

MOV M, A ;initial score for P2

MVI A,090H ;8255 INITIALISATION

OUT 003H

INIT: MVI A,030H

MOV B,A

CALL OUTPUT

CALL CMDOUT

CALL CMDOUT

MVI A,038H ;8 BIT, 2 LINES, 5X8 DISP

CALL CMDOUT

MVI A,008H ;DISPLAY OFF

CALL CMDOUT

MVI A,001H ;CLEAR DISPLAY

CALL CMDOUT

MVI A,006H ;ENTRY MODE SET, SHIFT AND INCREMENT

CURSOR

CALL CMDOUT

MVI A,00CH ;DISPLAY ON CURSOR, BLINKING OFF

CALL CMDOUT

DISPW1: MVI A, 01H; CLEARING DISPLAY

CALL CMDOUT

MVI A, 84H

1 | P a g e

CALL CMDOUT

LXI H, WD1 ; POINTER TO WD1 STRING

A1: MOV A, M

CPI 00H

JZ DISP1 ;ZERO MEANS WE HAVE REACHED END OF

WORD

CALL DTAOUT

INX H ;GO TO THE NEXT BIT IN THE WORD

JMP A1

LXI H, Birds; POINTER TO birdstart BIRDSTART WILL BE

THE LABEL FOR STORING THE STACK OF BIRDS. USE FORMAT AS

GIVYEN. NEED NOT DEFINE MEMORY LOCATIONS.

DISP1: CALL DELAY

A2: MVI A,001H

CALL CMDOUT

MVI A, 0C3H

CALL CMDOUT

A3: MOV A, M

CPI 00H

JZ notfly

CPI 01H

JZ fly

CALL DTAOUT

INX H

JMP A3 ;display bird name

notfly: MVI B, 00H

INX H

JMP POLL

fly: MVI B, 01H

2 | P a g e

INX H

JMP POLL

POLL: MVI A, 10010000B ;8255 INITIALISATION ;IT IS

KEEPING TRACK OF RECEIVING INPUTS AND WORKING ON C. AS

LONG AS C IS LESS THAN

OUT 03H

MVI C, 03H

L1: MVI D, 0FFH

MVI E, 0FFH

READ1: IN 00H

ANI 03H

CPI 02H; ; comparision being made for the

switch of player 1

JZ CALC2

CPI 01H; ;player2 PRESSED

JZ CALC1

DCX D

MOV A,E

ORA D

JNZ READ1

DCR C

MOV A, C

CPI 00H

JNZ L1

JZ CALC3

CALC2: PUSH H

LXI H, 8000H

MOV D, M

INX H

3 | P a g e

MOV E, M ; get scores in D, E

registers

MOV A, B; get value for bird ; PROCESSING OF

INPUT GIVEN BY PLAYER1

CPI 01H

JNZ NEGP1

INR D

LXI H, 8000H

MOV M, D

CALL DISPS

POP H

JMP DISP1; go to display for next animal

NEGP1: MOV A, D

CPI 00H

JZ NOP1

DCR D

LXI H, 8000H

MOV M, D

NOP1: CALL DISPS

POP H

JMP DISP1;

CALC1: PUSH H ; WHEN P2 HAS PRESSED

LXI H, 8000H ; RETRIEVES ORIGINAL SCORES OF P1 AND P2

MOV D, M

INX H

MOV E, M ; get scores in D, E

registers

MOV A, B; get value for bird PROCESSING IF

INPUT COMES FROM PLAYER1. WE CHECK IF INPUT IS

RIGHT/WRONG IN ACCORDANCE WITH THE CURRENT BIRD AND

HENCE INCREMENT/DECREMENT THE SCORE

4 | P a g e

CPI 01H ;BITS FROM ORIGINAL BIRD WORD THAT WERE

STORED IN B ARE NOW BEING COMPARED WITH 01 WHICH IS

FLYING KE LIYE

JNZ NEGP2 ; BIRD IS NOT FLYING. BUT P2 HAS SAID THAT

THE BIRD FLIES

INR E ; SCORE OF P2

LXI H, 8001H

MOV M, E

CALL DISPS

POP H

JMP DISP1 ;go to display for next animal:: THIS

WAS ERROR PREVIOUSLYYYYYYYYYYYYYYYYYYYYYY . EARLIER

WAS A1

NEGP2: MOV A, E

CPI 00H

JZ NOP2

DCR E

LXI H, 8001H

MOV M, E

NOP2: CALL DISPS

POP H

JMP DISP1;

CALC3: PUSH H

LXI H, 8000H

MOV D, M

INX H

MOV E, M ; get scores in D, E

registers

MOV A, B ;PROCESSING OF FINAL SCORES INCASE

NO PLAYER GIVES AN INPUT

5 | P a g e

CPI 00H ;B IS THE REGISTER THAT IS STORING

VALUES OO/O1. B=00 MEANS BIRD CANT FLY. ALSO NO SWITCH

BEING PRESSED MEANS SAME, THAT'S WHY WE ARE HERE IN

THIS LOOP. HENCE BOTH ARE CORRECT.

;NOW MOVE TO LABEL OF BOTH CORRECT WHERE BOTH WILL

BE REWARDED.

JNZ SCRN

INR D

INR E

LXI H, 8000H

MOV M, D

INX H

MOV M, E

SCRN: CALL DISPS

POP H

JMP DISP1 ;disp GO TO DISPLAY FOR NEXT ANIMAL

DELAY: PUSH PSW

PUSH B

PUSH D

LXI D, 0008H

M1: LXI B, 0FFFFH

T1: DCX B

MOV A,C

ORA B

JNZ T1

DCX D

MOV A,E

ORA D

JNZ M1

POP D

POP B

6 | P a g e

POP PSW

RET

DISPS: MVI A, 82H

CALL CMDOUT

MOV A, D

CALL HTD

MOV A, B

CALL DTAOUT

MOV A, C

CALL DTAOUT

MVI A, 86H

CALL CMDOUT

MOV A, E

CALL HTD

MOV A, B

CALL DTAOUT

MOV A, C

CALL DTAOUT

MVI A,20H ; SPACE

CALL DTAOUT

MVI A,20H ; SPACE

CALL DTAOUT

MVI A,20H ; SPACE

CALL DTAOUT

MVI A,20H ; SPACE

CALL DTAOUT

MVI A,20H

CALL DTAOUT

MVI A,20H

CALL DTAOUT

MVI A,20H

CALL DTAOUT

7 | P a g e

MVI A,20H

CALL DTAOUT

RET

HTD: MVI B, 00H

MVI C, 00H

REPD: CPI 09H

JC IND

JZ IND

INR B

SUI 0AH

JMP REPD

IND: ADI 30H

MOV C, A

MOV A, B

ADI 30H

MOV B, A

RET

WD1: .DB "CHIDIYA UDD",00

Birds: .DB "CROW",01

.DB "EAGLE",01

.DB "BILLI",00

.DB "NSIT",00

.DB "TITLI",01

.DB "OSTRITCH",00

.DB "PANCHHI",01

.DB "SPACE SHIP",01

.DB "PEACOCK",01

.DB "SPIDER MAN",01

.DB "KUTTA",00

.DB "HANUMAN",01

8 | P a g e

.DB "WHISKEY",00

.DB "BED",00

.DB "MOSQUITO",01

.DB "KITE",01

.DB "UNDERWEAR",00

.DB "PIGEON",01

.DB "VULTURE",01

.DB "ALBATROSS",01

.DB "COWBIRD",01

.DB "CHEETAH",00

.DB "COW",00

.DB "CROCODILE",00

.DB "HAWK",01

.DB "CANNABIS",00

.DB "PELICAN",01

.DB "HELLICOPTER",01

.DB "VIREO",01

.DB "WOODPECKER",01

.DB "BALLS",00

.DB "BAT",01

.DB "SQUIRREL",00

.DB "BULBUL",00

.DB "HONEYBEE",01

.DB "OWL",01

.DB "KUKUR",00

.DB "DOVE",01

.DB "BOOTS",01

.DB "BUSHTIT",01

.DB "LIZZARD",00

.DB "COCKROACH",00

.DB "MURGI",01

.DB "HERON",01

.DB "MAGPIE",01

9 | P a g e

.DB "MAGGI",00

.DB "5 STAR",00

.DB "BAGPIPER",00

.DB "SANDPIPER",01

.DB "YOU",00

;Standard lcd functions: read them through

CMDOUT: MOV B,A ;SAVE

CALL CHK

OUTPUT: MVI A,081H;RS=0,RW=0,EN=1

OUT 002H

RET

DTAOUT: MOV B,A;SAVE DATA BYTE

CALL CHK

MVI A,005H;RW=0,RS=1,EN=1

OUT 002H

MOV A,B;RESTORE

OUT 001H

RET

CHK: MVI A,092H;SET B AS INPUT PORT

OUT 003H

READ: MVI A,083H;RW=1,RS=0,EN=1;ENABLE HIGH

OUT 002H

IN 001H; CHECK D7

RLC;CARRY

MVI A,082H;RW=1,RS=0,EN=0

OUT 002H

JC READ ;LOOP TILL BUSY

MVI A,081H;RS=0,RW=0,EN=HIGH

10 | P a g e

MVI A,090H ;SET B AS OUTPUT

OUT 003H

MOV A,B

OUT 001H

RET

END

11 | P a g e

CODE DESCRIPTION

Here is a brief summary of the code and the functions performed by

the various labels:

The rule of the game is that if a creature flies, the player has to press

a switch. A value of 01 corresponds to a flying creature and a value of

00 corresponds to a non-flying creature. Hence if at any stage a player

is pressing the switch, he is saying that the creature flies and is thus

giving an input of 01. Hence if at any stage a player is not pressing the

switch, he is saying that the creature can not flies and is thus giving an

input of 00.

INIT : used for initialisation of the LCD.

DISPW1: used for displaying the word Chidiya Udd.

DISP1: used for displaying the names of the creatures using the

lookup table stored later.

Every creature name in the lookup tabke ends with 00/01.

A value of 00 indicates that the creature can not fly.

A value of 01 indicates that the creature can fly.

The register B is used for storing these values.

Fly: This label is used for storing the value 00 in the register B

corresponding to a non-flying animal.

Notfly: This label is used for storing the value 01 in the register B

corresponding to flying animal.

Poll: It is used to implement a time delay during which the name of a

creature continues to display. As long as the name of the creature is

being displayed, inputs can be accepted from either of the two

players.

12 | P a g e

READ1: It is used to accept and read the values of the inputs given by

players 1 and 2. If player 1 has pressed the switch first, the execution

moves to Calc2. If player 2 has pressed the switch first, the execution

moves to Calc1.

Calc2: The score of player1 is loaded from the memory. The input

given by player 1 is compared with the value corresponding to the

creature scored in register B. If the 2 values match, the score is

incremented, otherwise decremented. If the score is 00, no change in

implementation in case, player 1 has given the wrong input i.e. no

decrementing takes place.

Calc1: The score of player2 is loaded from the memory. The input

given by player 2 is compared with the value corresponding to the

creature scored in register B. If the 2 values match, the score is

incremented, otherwise decremented. If the score is 00, no change in

implementation in case, player 1 has given the wrong input i.e. no

decrementing takes place.

Calc3: The game will continue to receive inputs corresponding to a

particular animal as long as the delay implemented by the Poll label is

in process. Once the time of the delay has passed, and if in this while

no switch has been pressed by any player, that implies both the

players are saying that the creature can not fly i.e. they are giving an

input of 00. If this value matches with the value corresponding to the

creature stored in register B, scores of both players are incremented.

DISPS: This is the function that is used for displaying the score.

HTD, REPD , IND: These are used for conversion of hexadecimal score

to binary values.

Birds: This indicates the lookup table i.e. the stack of birds which is

stored in the memory.

13 | P a g e

TESTING THE BOARD

Testing is an integral part of the final project completeion. We hence

took the following measures:

Checked all connections using a multimeter

Checked all control signals on the oscilloscope.

Checked the functioning of LCD multiple times as this was the

part which gave us most of the trouble.

Checked the functioning of 8255 on the oscilloscope.

Tested the SID-SOD program.

Tested the inputs and output of 8085 for any discrepancies.

PROBLEMS FACED DELAY TO PCB MANUFACTURER: The PCB manufacturers delay in

delivering our board led to a quite some lag in getting started

with the work.

DELAY DUE TO LCD: Firstly our 3 LCD’s turned out to be defective .

Secondly problem arose due to some soldering issue in LCD which

made the display on the LCD flicker continuously . so we had to

adjust the lcd everytime we displayed something on it. Thirdly we

got our lcd finally working after multiple attempts. Everytime we

passed some data into the lcd instead of the data being displayed

only boxes were displayed. The mistake which we

1 | P a g e

PROJECT PROGRESS USING GANTT

CHART A Gantt chart is an excellent war to illustrate the start and finish dates of the

terminal elements and summary elements of a project. It also shows the

dependency of one task on another.

The following was originally proposed chart of events.

2 | P a g e

But as the time followed we had to change the analysis. The final

gantt chart is as follows.

3 | P a g e

It is clear from the charts that ,we did fell behind schedule, but we

worked harder and completed the project before the final

deadline.

Gantt Chart is a wonderfull tool which highly elaborately helps the

members to work according to the schedule. We have grown to

appreciate its usefulness .

CONCLUSION

We succeeded in finishing our project though with some delay but

with amazing results.

This experience has been wonderful and it taught us how to be

patient and how to work together without getting on each others

nerves. It also taught us how to manage time and most importantly

taught us a lot of things which we otherwise would have remained

unaware of.

BIBLIOGRAPHY

Ramesh S. Gaonkar: “Microprocessor Architecture, Programming,

and applications with the 8085”

Dhananjay V. Gadre and Nehul Malhotra:“Tiny AVR

microcontroller projects for the Evil Genius”

www.alldatasheet.com

www.sparkfun.com

www.google.com

4 | P a g e