Embedded Systems Building and Programming Embedded Devices
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PDF generated at: Mon, 28 Oct 2013 18:37:03 UTC Contents Articles Wikibooks:Collections Preface 1 Embedded Systems/Embedded Systems Introduction 3 Embedded Systems/Terminology 7 Microprocessor Basics 10 Embedded Systems/Microprocessor Introduction 10 Embedded Systems/Embedded System Basics 11 Embedded Systems/Microprocessor Architectures 13 Embedded Systems/Programmable Controllers 16 Embedded Systems/Floating Point Unit 18 Embedded Systems/Parity 20 Embedded Systems/Memory 21 Embedded Systems/Memory Units 24 Programming Embedded Systems 25 Embedded Systems/C Programming 25 Embedded Systems/Assembly Language 31 Embedded Systems/Mixed C and Assembly Programming 34 Embedded Systems/IO Programming 42 Embedded Systems/Serial and Parallel IO 43 Embedded Systems/Super Loop Architecture 44 Embedded Systems/Protected Mode and Real Mode 46 Embedded Systems/Bootloaders and Bootsectors 47 Embedded Systems/Terminate and Stay Resident 48 Real Time Operating Systems 49 Embedded Systems/Real-Time Operating Systems 49 Embedded Systems/Threading and Synchronization 51 Embedded Systems/Interrupts 57 Embedded Systems/RTOS Implementation 59 Embedded Systems/Locks and Critical Sections 62 Embedded Systems/Common RTOS 65 Embedded Systems/Common RTOS/Palm OS 67 Embedded Systems/Common RTOS/Windows CE 68 Embedded Systems/Common RTOS/DOS 69 Embedded Systems/Linux 70 Interfacing 73 Embedded Systems/Interfacing Basics 73 Embedded Systems/External ICs 74 Embedded Systems/Low-Voltage Circuits 74 Embedded Systems/High-Voltage Circuits 76 Particular Microprocessor Families 78 Embedded Systems/Particular Microprocessors 78 Embedded Systems/Intel Microprocessors 81 Embedded Systems/PIC Microcontroller 82 Embedded Systems/8051 Microcontroller 88 Embedded Systems/Freescale Microcontrollers 92 Embedded Systems/Atmel AVR 93 Embedded Systems/ARM Microprocessors 111 Embedded Systems/AT91SAM7S64 114 Embedded Systems/Cypress PSoC Microcontroller 115 Appendices 121 Embedded Systems/Common Protocols 121 Embedded Systems/Where To Buy 123 Resources and Licensing 124 Embedded Systems/Resources 124 Embedded Systems/Licensing 126 References Article Sources and Contributors 127 Image Sources, Licenses and Contributors 129 Article Licenses License 130 Wikibooks:Collections Preface 1 Wikibooks:Collections Preface This book was created by volunteers at Wikibooks (http:/ / en. wikibooks. org). 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There are no comprehensive resources available over the internet which deal with the various design and implementation issues of this technology. Intellectual property regulations of many corporations are partly to blame for this and also the tendency to keep technical know-how within a restricted group of researchers. Before embarking on the rest of this book, it is important first to cover exactly what embedded systems are, and how they are used. This wikibook will attempt to cover a large number of topics, some of which apply only to embedded systems, but some of which will apply to nearly all computers (embedded or otherwise). As such, there is a chance that some of the material from this book will overlap with material from other wikibooks that are focused on topics such as low-level computing, assembly language, computer architecture, etc. But we will first start with the basics, and attempt to answer some questions before the book actually begins. What is an Embedded Computer? The first question that needs to be asked, is "What exactly is an embedded computer?" To be fair, however, it is much easier to answer the question of what an embedded computer is not, than to try and describe all the many things that an embedded computer can be. An embedded computer is frequently a computer that is implemented for a particular purpose. In contrast, an average PC computer usually serves a number of purposes: checking email, surfing the internet, listening to music, word processing, etc... However, embedded systems usually only have a single task, or a very small number of related tasks that they are programmed to perform. Every home has several examples of embedded computers. Any appliance that has a digital clock, for instance, has a small embedded microcontroller that performs no other task than to display the clock.