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<H3><a name="comments"></a>Comments</H3>
<P>Comments are useful for documenting the source program. The assembler recognizes
the semicolon (<CODE>;</CODE>) as a comment delimiter character. Any character
or sequence of characters preceded by a semicolon is considered a comment. Comments
can occupy an entire line, or can be placed at the end of a source statement.</P>
<P><I>Examples:</I></P>
<CODE>
<BLOCKQUOTE>; This comment occupies an entire line</BLOCKQUOTE>
<BLOCKQUOTE>LDAC 1000 ; This is a trailing comment</BLOCKQUOTE>
</CODE>
<p> </p>
<H3><a name="numconst"></a>Numeric Constants</H3>
<P>Numeric constants can be used in source statements. If there is no postfix,
the assembler assumes the number is decimal.</P>
<TABLE CELLSPACING=0 BORDER=0 CELLPADDING=7>
<TR>
<TD VALIGN="TOP"> <P><I>number</I></P></TD>
<TD VALIGN="TOP"> <P>can be one of the following:</P>
<UL>
<LI><I>bin_num</I><CODE>B</CODE></LI>
<LI><I>dec_num</I> (or <I>dec_num</I><CODE>D</CODE>)</LI>
<LI><I>oct_num</I><CODE>O</CODE> (or <I>oct_num</I><CODE>Q</CODE>)</LI>
<LI><I>hex_num</I><CODE>H</CODE></LI>
</UL>
<P>Lowercase equivalences are allowed: <CODE>b</CODE>, <CODE>d</CODE>, <CODE>o</CODE>,
<CODE>q</CODE>, <CODE>h</CODE></P></TD>
</TR>
<TR>
<TD VALIGN="TOP"> <P><I>bin_num</I></P></TD>
<TD VALIGN="TOP"> <P>is a binary number consisting of the digits '<CODE>0</CODE>'-'<CODE>1</CODE>'
and ending with a '<CODE>B</CODE>' or '<CODE>b</CODE>'.</P>
<P><I>Examples:</I></P>
<BLOCKQUOTE><CODE>11000101B</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>1011B</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>1110110b</CODE></BLOCKQUOTE></TD>
</TR>
<TR>
<TD VALIGN="TOP"> <P><I>dec_num</I></P></TD>
<TD VALIGN="TOP"> <P>is a decimal number consisting of the digits '<CODE>0</CODE>'-'<CODE>9</CODE>',
optionally followed by '<CODE>D</CODE>' or '<CODE>d</CODE>'.</P>
<P><I>Examples:</I></P>
<BLOCKQUOTE><CODE>364</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>7534D</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>435d</CODE></BLOCKQUOTE></TD>
</TR>
<TR>
<TD VALIGN="TOP"> <P><I>oct_num</I></P></TD>
<TD VALIGN="TOP"> <P>is an octal number consisting of the digits '<CODE>0</CODE>'-'<CODE>7</CODE>'
and ending with an '<CODE>O</CODE>', '<CODE>o</CODE>', '<CODE>Q</CODE>'
or '<CODE>q</CODE>'.</P>
<P><I>Examples:</I></P>
<BLOCKQUOTE><CODE>77O</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>542o</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>2324q</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>34241Q</CODE></BLOCKQUOTE></TD>
</TR>
<TR>
<TD VALIGN="TOP"> <P><I>hex_num</I></P></TD>
<TD VALIGN="TOP"> <P>is a hexadecimal number consisting of '<CODE>0</CODE>'-'<CODE>9</CODE>'
and '<CODE>a</CODE>'-'<CODE>f</CODE>' or '<CODE>A</CODE>'-'<CODE>F</CODE>'
ending with a '<CODE>H</CODE>', or '<CODE>h</CODE>'.</P>
<P><I>Examples:</I></P>
<BLOCKQUOTE><CODE>84H</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>ABDEh</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>f12aH</CODE></BLOCKQUOTE></TD>
</TR>
</TABLE>
<H3><a name="asmdir" id="asmdir"></a>Assembler Directives</H3>
<P>The assembly process can be controlled by assembler directives. The assembler
interprets the assembler directives instead of translating them into machine
instructions. The assembler supports the following directives:</P>
<TABLE BORDER CELLSPACING=1 CELLPADDING=7>
<TR>
<TD VALIGN="MIDDLE" BGCOLOR="#c0c0c0"> <P><B>Directive</B></P></TD>
<TD VALIGN="MIDDLE" BGCOLOR="#c0c0c0"> <P><B>Description</B></P></TD>
</TR>
<TR>
<TD VALIGN="TOP"> <P><CODE>ORG <address></CODE></P></TD>
<TD VALIGN="TOP"> <P>Assemble the subsequent source statements starting at
the specified address, <CODE><address></CODE>.</P>
<P><I>Examples:</I></P>
<BLOCKQUOTE><CODE>ORG 1123H ; Start assembling at address 4387</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>ORG 567o ; Start assembling at address 375</CODE></BLOCKQUOTE></TD>
</TR>
<TR>
<TD VALIGN="TOP"> <P><CODE>DB <number></CODE></P></TD>
<TD VALIGN="TOP"> <P>Store the specified 1-byte constant <CODE><number></CODE>
in memory.</P>
<P><I>Examples:</I></P>
<BLOCKQUOTE><CODE>DB 11 ; Store the 8-bit constant 11 in memory</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>DB 333o ; Store the 8-bit constant 219 in memory</CODE></BLOCKQUOTE></TD>
</TR>
<TR>
<TD VALIGN="TOP"> <P><CODE>DW <number></CODE> </TD>
<TD VALIGN="TOP"> <P>Store the specified 2-byte constant <CODE><number></CODE>
in memory. The assembler initializes the memory with the least significant
byte first.</P>
<P><I>Examples:</I></P>
<BLOCKQUOTE><CODE>DW 23785 ; Store the 16-bit constant 23785 in memory</CODE></BLOCKQUOTE>
<BLOCKQUOTE><CODE>DW af43h ; Store the 16-bit constant 44867 in memory</CODE></BLOCKQUOTE></TD>
</TR>
</TABLE>
<h3><a name="labels"></a>Assembler Labels</h3>
<p>The assembler also supports jump to lables of the form label_name: (notice
the : after the label name). The labels are not case censetive.</p>
<p>Example:</p>
<p>JMP MyLabel</p>
<p>....</p>
<p>MyLabel: ....</p>
<H3><A NAME="asmprog">Assembling a Program</A></H3>
<OL>
<LI>At the main window, enter the assembly program in the text box.</LI>
<LI>Enter the starting memory location where the program will be stored in the
<B>Memory Location</B> text field.</LI>
<LI>Click the <B>Assemble</B> button. A dialog box will open displaying the
results of the assembly process.</LI>
</OL>
<HR WIDTH="75%">
<H3><A NAME="viewres">Viewing the Last Assembly Results</A></H3>
<P>At the main window, click on the <B>View Results</B> button. A dialog box will
open displaying the last assembly results.</P>
<p> </p>
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