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+<!-- $Id$ -->
+
+<chapter>
+<chapterinfo>
+	<title>JTAG Tools Internals</title>
+</chapterinfo>
+
+<para>
+This chapter is primarily intented for JTAG Tools hackers.
+</para>
+
+<sect1>
+<sect1info>
+	<title>JTAG Declarations Files</title>
+</sect1info>
+
+<para>
+JTAG declarations files are located in directory <filename>data</filename>. The files contains
+common part specific JTAG informaions in parseble form, e.g. list of the JTAG commands, boundary
+scan register, list of JTAG registers, etc.
+</para>
+
+<para>
+Syntax of the JTAG declaration file is defined in following subsections.
+</para>
+
+<sect2>
+<sect2info>
+	<title>General rules</title>
+</sect2info>
+
+<para>
+JTAG declaration file is text file which consist of lines. Empty lines are ignored. Text after
+first <constant>#</constant> on the line to the end of line is ignored. This is useful for comments.
+All other lines are significant.
+</para>
+
+<para>
+Each significant line consists of tokens separated by whitespace. Whitespace could be spaces and/or tabs.
+</para>
+
+</sect2>
+
+<sect2>
+<sect2info>
+	<title>Signal Definition</title>
+</sect2info>
+
+<para>
+Signal definition line consist of word <constant>pin</constant> followed by whitespace and signal name
+(without spaces in the name). Rest of the line should contain whitespace separated list of pins
+of the part. This list is is currently not used for any purpose in JTAG Tools.
+</para>
+
+</sect2>
+
+</sect1>
+
+</chapter>