Building iPhone OS Accessories: Use the iPhone Accessories API to Control and Monitor Devices (Books for Professionals by Professionals)

329 Pages·2010·5.42 MB·English

by  Ken Maskrey

CYAN YELLOW SPOT MATTE
MAGENTA BLACK
PANTONE 123 C
BOOKS FOR PROFESSIONALS BY PROFESSIONALS® Companion
eBook
Available
iPhone Accessory Development: The Next Frontier.
Building iPhone OS Accessories provides a hands-on look at Apple’s External
B
Accessory Framework and the iPhone Accessories API, which has now An in-depth examination of Apple’s External Accessory
u
been extended to the iPad, as well. You’ll learn how to create new, integrated
i
solutions that combine iPhone apps with dedicated hardware. ld Framework and the iPhone Accessory API.
i
The iPhone OS Accessories API expands the opportunities for innovative n
iPhone developers, allowing you to control and monitor external devices, g
whether you’ve built them yourself or obtained them from a third party.
i
•
Develop accessories and apps for the iPhone and iPod touch P
•
Use Apple’s External Accessory Framework to create hardware
h
and software interaction
• Control and monitor external devices using the iPhone o
Accessories API
n
•
Use the specific controller classes within the iPhone OS SDK
• e
Build and control your own accessory
• Learn about all the costs associated with becoming an accessory
O
developer before committing
This book is for iPhone, iPod touch, and iPad developers who want to write S
apps to control external accessories and hardware developers who want to
create accessories for iPhone OS devices. This includes embedded systems
A
programmers who have been left out of the iPhone gold rush until now.
The iPhone OS Accessories EAAccessory expands the market of developers c
Building
yet again, and this book is for all those developers wanting to use these
c
new APIs to control and monitor external devices—whether self-built or ac-
quired from other sources. e
iPhone OS
s
s
o
r Accessories
i
e
s

Use the iPhone Accessories API to Control and Monitor Devices
M
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s
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COMPANION eBOOK SEE LAST PAGE FOR DETAILS ON $10 eBOOK VERSION ISBN 978-1-4302-2931-5 ey Ken Maskrey
55999
US $59.99
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this print for content only—size & color not accurate Trim: 7.5 x 9.25 spine = 0.75" 328 page count

Building iPhone OS
Accessories
Use the iPhone Accessories API to
Control and Monitor Devices

■ ■ ■
Ken Maskrey

i
Building iPhone OS Accessories. Use the iPhone Accessories API to Control and Monitor
Devices
Copyright © 2010 by Ken Maskrey
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ISBN-13 (pbk): 978-1-4302-2931-5
ISBN-13 (electronic): 978-1-4302-2932-2
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ii
To JB, for helping me make it through this endeavor.

iii
Contents at a Glance
■Contents at a Glance.......................................................................................iv
■Contents..........................................................................................................v
■About the Author............................................................................................ix
■About the Technical Reviewer.........................................................................x
■Preface...........................................................................................................xi
Part I: What is an Accessory?.............................................................................1(cid:1)
■Chapter 1: Accessory Overview.......................................................................3(cid:1)
■Chapter 2: EAAccessory Framework.............................................................21(cid:1)
■Chapter 3: EA Framework Design Patterns...................................................47(cid:1)
Part II: Project Walkthrough.............................................................................77(cid:1)
■Chapter 4: The Game Controller....................................................................79(cid:1)
■Chapter 5: Specifying a Pong Game............................................................103(cid:1)
■Chapter 6: Coding a Pong Game..................................................................119(cid:1)
■Chapter 7: Adding the Game Controller.......................................................141(cid:1)
■Chapter 8: Improving the Design.................................................................165(cid:1)
■Chapter 9: Apple Developer Programs........................................................179(cid:1)
Part III: Designing an Accessory ....................................................................191(cid:1)
■Chapter 10: Hardware Design......................................................................193(cid:1)
■Chapter 11: Firmware..................................................................................221(cid:1)
■Chapter 12: Everything Else........................................................................241(cid:1)
■Appendix......................................................................................................259
■Index............................................................................................................305
iv
Contents
■Contents at a Glance.......................................................................................iv(cid:1)
■Contents..........................................................................................................v(cid:1)
■About the Author............................................................................................ix(cid:1)
■About the Technical Reviewer.........................................................................x(cid:1)
■Preface...........................................................................................................xi(cid:1)

Part I: What is an Accessory?.............................................................................1(cid:1)
■Chapter 1: Accessory Overview.......................................................................3(cid:1)
Being Different........................................................................................................................................................3(cid:1)
Accessories.............................................................................................................................................................4(cid:1)
Uses of Accessories................................................................................................................................................4(cid:1)
Accessories: A View From Above............................................................................................................................6(cid:1)
Credit Card Reader................................................................................................................................................11(cid:1)
But I’m a Programmer...........................................................................................................................................14(cid:1)
The Software Approach........................................................................................................................................15(cid:1)
The Pong Game.....................................................................................................................................................16(cid:1)
Embedded Systems..............................................................................................................................................17(cid:1)
Building an Accessory...........................................................................................................................................19(cid:1)
Summary..............................................................................................................................................................19(cid:1)
■Chapter 2: EAAccessory Framework.............................................................21(cid:1)
Frameworks..........................................................................................................................................................21(cid:1)
Streams................................................................................................................................................................22(cid:1)
Protocols...............................................................................................................................................................23(cid:1)
More on Protocols.................................................................................................................................................26(cid:1)
The EA Framework................................................................................................................................................32(cid:1)
EAAccessory Class Properties.........................................................................................................................32(cid:1)
EAAccessory Class Constants..........................................................................................................................38(cid:1)
EAAccessoryManager Class.............................................................................................................................38(cid:1)
EASession........................................................................................................................................................41(cid:1)
Summary..............................................................................................................................................................45

v
■ CONTENTS
■Chapter 3: EA Framework Design Patterns...................................................47(cid:1)
Object-Oriented Programming..............................................................................................................................47(cid:1)
The Basics of OOP............................................................................................................................................49(cid:1)
The UIApplication Class...................................................................................................................................54(cid:1)
Delegation.............................................................................................................................................................57(cid:1)
OOP and Delegation..............................................................................................................................................61(cid:1)
Model-View-Controller..........................................................................................................................................64(cid:1)
Notification............................................................................................................................................................66(cid:1)
EA Pattern.............................................................................................................................................................72(cid:1)
Summary..............................................................................................................................................................73(cid:1)
Part II: Project Walkthrough.............................................................................77(cid:1)
■Chapter 4: The Game Controller....................................................................79(cid:1)
The Griffin iTrip.....................................................................................................................................................79(cid:1)
iTrip Dissected.................................................................................................................................................82(cid:1)
Game Controller Design........................................................................................................................................84(cid:1)
The Game Controller’s Functions.....................................................................................................................85(cid:1)
Electrical and Physical Design..............................................................................................................................88(cid:1)
Test Software........................................................................................................................................................90(cid:1)
Summary............................................................................................................................................................101(cid:1)
■Chapter 5: Specifying a Pong Game............................................................103(cid:1)
Keeping It Simple................................................................................................................................................103(cid:1)
Specification.......................................................................................................................................................103(cid:1)
Page One—Drawings....................................................................................................................................104(cid:1)
Developing Your Requirements......................................................................................................................112(cid:1)
Summary............................................................................................................................................................116(cid:1)
■Chapter 6: Coding a Pong Game..................................................................119(cid:1)
Architecture........................................................................................................................................................119(cid:1)
The Application Life Cycle..............................................................................................................................119(cid:1)
Pong Game Architecture................................................................................................................................126(cid:1)
The Application Delegate...............................................................................................................................128(cid:1)
The View Controller........................................................................................................................................128(cid:1)
The Nib...........................................................................................................................................................130(cid:1)
Summary............................................................................................................................................................138(cid:1)
■Chapter 7: Adding the Game Controller.......................................................141(cid:1)
The Game Controller Test Program.....................................................................................................................141(cid:1)
The Game Controller Object................................................................................................................................145(cid:1)
The Game Controller Interface.......................................................................................................................145(cid:1)
The Game Controller Implementation............................................................................................................146(cid:1)
View Controller Modifications........................................................................................................................156(cid:1)
Summary............................................................................................................................................................163(cid:1)
■Chapter 8: Improving the Design.................................................................165(cid:1)
Performance Concerns.......................................................................................................................................165(cid:1)
Security Concerns...............................................................................................................................................168(cid:1)
The Payment Card Industry............................................................................................................................169(cid:1)
Code Changes................................................................................................................................................174(cid:1)
Summary............................................................................................................................................................177(cid:1)
vi
■ CONTENTS
■Chapter 9: Apple Developer Programs........................................................179(cid:1)
Mac Developer....................................................................................................................................................179(cid:1)
iPhone Developer................................................................................................................................................180(cid:1)
Apple Developer Connection...............................................................................................................................182(cid:1)
Made For iPod/Works With iPhone......................................................................................................................183(cid:1)
Running a Business............................................................................................................................................183(cid:1)
Summary............................................................................................................................................................190(cid:1)
Part III: Designing an Accessory ....................................................................191(cid:1)
■Chapter 10: Hardware Design......................................................................193(cid:1)
Getting Started....................................................................................................................................................193(cid:1)
Design Process...................................................................................................................................................196(cid:1)
Parts (Processor) Selection............................................................................................................................197(cid:1)
Prototyping.....................................................................................................................................................203(cid:1)
Circuit Design.................................................................................................................................................205(cid:1)
PCB Design....................................................................................................................................................210(cid:1)
Fabrication.....................................................................................................................................................213(cid:1)
Integration and Testing..................................................................................................................................215(cid:1)
Summary............................................................................................................................................................219(cid:1)
■Chapter 11: Firmware..................................................................................221(cid:1)
I’m a PC...............................................................................................................................................................221(cid:1)
Compilers............................................................................................................................................................222(cid:1)
Programming......................................................................................................................................................223(cid:1)
Debugging...........................................................................................................................................................227(cid:1)
Your PCB.............................................................................................................................................................231(cid:1)
Structure.............................................................................................................................................................234(cid:1)
Chip Configuration..............................................................................................................................................238(cid:1)
Summary............................................................................................................................................................239(cid:1)
■Chapter 12: Everything Else........................................................................241(cid:1)
Tools and Test Equipment..................................................................................................................................241(cid:1)
Tools..............................................................................................................................................................242(cid:1)
Test Equipment..............................................................................................................................................247(cid:1)
Mechanical Design..............................................................................................................................................249(cid:1)
The Alternative to Custom Mechanical Design..............................................................................................252(cid:1)
Packaging...........................................................................................................................................................253(cid:1)
Business Processes............................................................................................................................................255(cid:1)
Summary............................................................................................................................................................257(cid:1)
Appendix.........................................................................................................259(cid:1)
PongViewController.h interface listing................................................................................................................259(cid:1)
PongViewController.m implementation listing....................................................................................................261(cid:1)
GameController.h................................................................................................................................................268(cid:1)
GameController.m...............................................................................................................................................269(cid:1)
pongViewController.h..........................................................................................................................................273(cid:1)
pongViewController.m.........................................................................................................................................275(cid:1)
pongAppDelegate.h.............................................................................................................................................285(cid:1)
pongAppDelegate.m............................................................................................................................................286(cid:1)
GameController.h................................................................................................................................................286(cid:1)
vii
■ CONTENTS
GameController.m...............................................................................................................................................287(cid:1)
pongViewController.h..........................................................................................................................................291(cid:1)
■Index............................................................................................................305
viii