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Remove unused header files; eliminate warnings

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git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3731 42af7a65-404d-4744-a932-0658087f49c3
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patacongo 2011-06-21 23:53:00 +00:00
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Documentation/NuttX.html
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@ -1627,6 +1627,30 @@
<td><br></td>
<td><hr></td>
</tr>
<tr>
<td><br></td>
<td>
<p><b>AVR-Specific Issues</b>.
The basic AVR port is solid and biggest issue for using AVR is its tiny SRAM memory and its Harvard architecture.
Because of the Harvard architecture, constant data that resides to flash is inaccessible using &quot;normal&quot; memory reads and writes (only SRAM data can be accessed &quot;normally&quot;).
Special AVR instructions are available for accessing data in FLASH, but these have not been integrated into the normal, general purpose OS.
</p>
<p>
Most NuttX test applications are console-oriented with lots of strings used for printf and debug output.
These strings are all stored in SRAM now due to these data accessing issues and even the smallest console-oriented applications can quickly fill a 4-8Kb memory.
So, in order for the AVR port to be useful, one of two things would need to be done:
</p>
<ol>
<li>
Don't use console applications that required lots of strings.
The basic AVR port is solid and your typical deeply embedded application should work fine.
Or,
</li>
<li>
Create a special version of printf that knows how to access strings that reside in FLASH (or EEPROM).
</li>
</ol>
</tr>
<tr>
<td><br></td>
<td>