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/* Copyright (c) 2004-2006 Joerg Wunsch
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE. */
/* $Id: all-demos.dox 1124 2006-08-29 19:45:06Z joerg_wunsch $ */
/** \defgroup demos Demo projects
Various small demo projects are provided to illustrate several
aspects of using the opensource utilities for the AVR controller
series. It should be kept in mind that these demos serve mainly
educational purposes, and are normally not directly suitable for use
in any production environment. Usually, they have been kept as
simple as sufficient to demonstrate one particular feature.
The \ref demo_project "simple project" is somewhat like the "Hello
world!" application for a microcontroller, about the most simple
project that can be done. It is explained in good detail, to allow
the reader to understand the basic concepts behind using the tools
on an AVR microcontroller.
The \ref largedemo "more sophisticated demo project" builds on top
of that simple project, and adds some controls to it. It touches
a number of avr-libc's basic concepts on its way.
A \ref stdiodemo "comprehensive example on using the standard IO facilities"
intends to explain that complex topic, using a
practical microcontroller peripheral setup with one RS-232
connection, and an HD44780-compatible industry-standard LCD
display.
The \ref twi_demo project explains the use of the two-wire hardware
interface (also known as "I2C") that is present on many AVR
controllers.
Finally, the \ref asmdemo demo shows how C and assembly language
source files can collaborate within one project. While the overall
project is managed by a C program part for easy maintenance,
time-critical parts are written directly in manually optimized
assembly language for shortest execution times possible. Naturally,
this kind of project is very closely tied to the hardware design,
thus it is custom-tailored to a particular controller type and
peripheral setup. As an alternative to the assembly-language
solution, this project also offers a C-only implementation
(deploying the exact same peripheral setup) based on a more
sophisticated (and thus more expensive) but pin-compatible
controller.
While the simple demo is meant to run on about any AVR setup
possible where a LED could be connected to the OCR1[A] output,
the \ref largedemo "large" and \ref stdiodemo "stdio" demos are
mainly targeted to the Atmel STK500 starter kit, and the
\ref twi_demo "TWI" example requires a controller where some
24Cxx two-wire EEPPROM can be connected to. For the STK500
demos, the default CPU (either an AT90S8515 or an ATmega8515)
should be removed from its socket, and the ATmega16 that ships
with the kit should be inserted into socket SCKT3100A3. The
ATmega16 offers an on-board ADC that is used in the
\ref largedemo "large" demo, and all AVRs with an ADC feature
a different pinout than the industry-standard compatible
devices.
In order to fully utilize the \ref largedemo "large" demo, a
female 10-pin header with cable, connecting to a 10 kOhm
potentiometer will be useful.
For the \ref stdiodemo "stdio" demo, an industry-standard
HD44780-compatible LCD display of at least 16x1 characters
will be needed. Among other things, the
<a href="http://ssl.bulix.org/projects/lcd4linux/">LCD4Linux</a>
project page describes many things around these displays,
including common pinouts.
*/