Universal Display Book for PIC Microcontrollers

194 Pages·2008·4.951 MB·English

by  Richard Grodzik

Richard Grodzik
R.Grodzik
UniversalDisplayBook
forPICMicrocontrollers

R. Grodzik
Universal Display Book
for PIC Microcontrollers
ElektorInternationalMediaBV
Postbus11
6114ZGSusteren
TheNetherlands
Acknowledgement
I would like to dedicate this book to my mother – Walentyna, without whose support,
kindnessandobjectivity,thisbookwouldneverhavebeenpossible.
RichardGrodzik,september2007.
Allrightsreserved.Nopartofthisbookmaybereproducedinanymaterialform,includ-
ingphotocopying,orstoringinanymediumbyelectronicmeansandwhetherornottran-
siently or incidentally to some other use of this publication, without the written
permissionofthecopyrightholderexceptinaccordancewiththeprovisionsoftheCopy-
right,DesignsandPatentsAct1988 orunderthetermsofalicenceissuedby theCopy-
right Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1P 9HE.
Applications for the copyright holder’s written permission to reproduce any part of this
publicationshouldbeaddressedtothepublishers.
Thepublishershaveusedtheirbesteffortsinensuringthecorrectnessoftheinformation
containedinthisbook.Theydonotassume,andherebydisclaim,anyliabilitytoanyparty
foranylossordamagecausedbyerrorsoromissionsinthisbook,whethersucherrorsor
omissionsresultfromnegligence,accidentoranyothercause.
BritishLibraryCataloguinginPublicationData
AcataloguerecordforthisbookisavailablefromtheBritishLibrary
ISBN978-0-905705-73-6
NUR980
Prepressproduction:Autronic,Blaricum
Designcover:HelfrichOntwerpbureau,Deventer
FirstpublishedintheUnitedKingdom2008
PrintedintheNetherlandsbyWilco,Amersfoort
©ElektorElectronics2008
089007/UK
Preface
Thisbookisapracticalintroductiontousingandinterfacingmanytypesofelectronicdis-
plays to Arizona Microchip’s range of embedded microcontrollers, commonly know as
‘PIC chips’. From the simple LED to colour graphic displays, the reader is shown the
hardwareinterfacerequirementsandthesoftwareprogrammingbothinAssemblerand/or
MPLABC18Ccompilertoachieveafunctioningdisplay.Inaddition,asmallintroduc-
tory tutorial for using the freely available ‘EAGLE’ PCB/Schematic CAD tool is in-
cluded.
ThePICmicrocontrollerscoveredinthisbookincludethePIC12C508,PIC12F629/675,
PIC16F84,PIC16F876,PIC18F252, PIC18F452andthe PIC18F4550.
Toutilisethevariousdisplays,manycompletecasestudies,fromasimpleeggtimerusing
asingle 7-segmentLEDdisplay toanelectroniccompasswithcolour graphic LCDdis-
playareincludedinthisbook.
I hope that the reader enjoys constructing some of these projects, since complete sche-
maticdrawingsareincluded,includingthesourcecodeandHexdumpforthevariousPIC
microcontrollers.
Inaddition,allthesourcecodeexamplesinthebookmaybedownloadedfromtheelec-
tor.comwebsiteandthePDFdata-sheetfilesfromtherelevantmanufacturer’swebsites
forallthecasestudies.
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TableofContents
Table of Contents
Preface 5
1 Lightemittingdiodes 9
1.1 Historyofthelightemittingdiode 9
1.2 LEDcharacteristicsandparameters 10
1.3 PICinterfaceforLEDcircuits–designandprogramming 14
1.4 CaseStudyRGBVGAmonitortester 32
1.5 CaseStudyChristmaslight 35
1.6 CaseStudy3channelsoundtolight 39
2 Whitelightemittingdiodes 44
2.1 PWMLEDbrightnessandvoltagecontrol 44
2.2 TPS60403chargepumpvoltageinverter 49
2.3 TPS61040lowpowerDC/DCboostconverter 50
2.4 LT1054switched-capacitorvoltageconverter 52
2.5 MAX1848whiteLEDstep-upconverter 53
3 7-segmentDisplays 55
3.1 Fundamentalsof7-segmentLEDdisplays 55
3.2 CaseStudyRS232Datamonitor 57
3.3 CaseStudy00to99minuteprogrammabletimer 65
3.4 CaseStudy4minuteeggtimer 69
4 B/WLiquidCrystalDisplays 77
4.1 IndustrystandardalphanumericalLCDdisplays 78
4.2 CaseStudyASCIIstringgenerator 87
4.3 CaseStudyRS232datamonitor 94
4.4 CaseStudyheartratemonitor-ProgramOXY.ASM 103
4.5 CaseStudyIICrealtimedigitalclock 114
5 GraphicLiquidCrystalDisplays 123
5.1 CaseStudyDensitronLM4068B/W100x64pixeldisplay 123
5.2 CaseStudysimplePDAusingtheNokia3310 129
5.3 Iconimageeditingsoftware 136
5.4 CaseStudyNokia3310GPSdigitalclock 140
5.5 CaseStudyNokia3510iElectroniccompass 155
5.6 CaseStudyNokia6100Epsondisplay8bitcolour 161
5.7 CaseStudyNokia6100Philipsdisplay16bitcolour 165
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TableofContents
6 OEMcolourGraphicDisplays 168
6.1 OLIMEX 168
6.2 TheMPS430-4619LCD(6100) 169
6.3 4DSYSTEMS 169
6.4 The4D-MICRO-LCD-320-PMD2DISPLAY 171
6.5 Display3000 173
6.6 ezLCD 174
6.7 REACHtech 176
7 Appendix 178
7.1 References 188
Index 191
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1Lightemittingdiodes
1 Light emitting diodes
TheLEDisasimpleindicatoravailableinavarietyofdifferentshapes,coloursandlevels
oflightintensity.Itcanbemadetostaypermanentlyon,flashonandoffatdifferentfre-
quencies, and vary its light output. To achieve this, an embedded microcontroller – the
PICchip–isused,wherebyaprogramcaneasilychangethefunctionalityoftheLED:for
useasstatus(ON/OFF)andalarmconditionsand,becauseitisavailableinalargerange
ofcolours,itcandifferentiatebetweenthestatusofmanysignalchannels.Alsoitcanbe
used to indicate an analogue quantity either by varying its brightness or by altering the
rateofflashing.LEDsareusedinmanyportableapplicationsbecauseoftheirlowcurrent
consumptionandsotheexamplesinthischapterconcentrateonlowpowerbatteryusage.
Inthischapter,anoverviewoftheLEDisgiven,togetherwithitshistoryandcharacteris-
tics. To enable the reader to design, construct and program the circuit, a simple
‘walk-through’usingaschematicanddesignpackageisincluded.Inadditionsimplesteps
in using the ‘MPLAB’ programming environment to program the PIC are included. Fi-
nallyseveralprojectsareincludedtodemonstratetheuseofLEDs.
1.1 History of the light emitting diode
Red,GreenandBlueLEDs
A light-emitting diode (LED) is a semiconductor device that emits incoherent nar-
row-spectrumlightwhenelectricallybiasedintheforwarddirectionofthep-njunction.
Thiseffectisaformofelectroluminescence.
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