\hypertarget{group__avr__signature}{}\doxysubsection{$<$avr/signature.h$>$\+: Signature Support}
\label{group__avr__signature}\index{$<$avr/signature.h$>$: Signature Support@{$<$avr/signature.h$>$: Signature Support}}
\begin{DoxyParagraph}{Introduction}

\end{DoxyParagraph}
The $<$\mbox{\hyperlink{signature_8h}{avr/signature.\+h}}$>$ header file allows the user to automatically and easily include the device\textquotesingle{}s signature data in a special section of the final linked E\+LF file.

This value can then be used by programming software to compare the on-\/device signature with the signature recorded in the E\+LF file to look for a match before programming the device.

\begin{DoxyParagraph}{A\+PI Usage Example}

\end{DoxyParagraph}
Usage is very simple; just include the header file\+:


\begin{DoxyCode}{0}
\DoxyCodeLine{\textcolor{preprocessor}{\#include <\mbox{\hyperlink{signature_8h}{avr/signature.h}}>}}
\end{DoxyCode}


This will declare a constant unsigned char array and it is initialized with the three signature bytes, M\+SB first, that are defined in the device I/O header file. This array is then placed in the .signature section in the resulting linked E\+LF file.

The three signature bytes that are used to initialize the array are these defined macros in the device I/O header file, from M\+SB to L\+SB\+: S\+I\+G\+N\+A\+T\+U\+R\+E\+\_\+2, S\+I\+G\+N\+A\+T\+U\+R\+E\+\_\+1, S\+I\+G\+N\+A\+T\+U\+R\+E\+\_\+0.

This header file should only be included once in an application. 