STD-editor

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0 height="100%"><tr> <td valign="top" width=155 BGCOLOR="#FFFFFF" TEXT="#080000" bgproperties="fixed" background="1f364643.gif"> <div> <A HREF="index.htm" TARGET="_top" TITLE="GenerExe Home of XPad crosscompiler tool"><U><B><IMG SRC="22b99940.gif" border=0 width="153" height="148" ALT="GenerExe Home Page" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></U></A></div> <bR> <DIV ALIGN="LEFT"></DIV> <div> <B> <TABLE BORDER="5" CELLPADDING="1" CELLSPACING="1" WIDTH="102" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" BGCOLOR=#FFFFCC > <tR> <tD VALIGN=TOP HEIGHT= 16 ><NOBR><div> <B>About XPad</B></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 145 WIDTH="86"><div> <A HREF="id56.htm" TARGET="_top" TITLE="IDE"><U>IDE</U></A></div> <div> <A HREF="id127.htm" TARGET="_top" TITLE="Hardware Configuration"><U>Hardware Configuration</U></A></div> <div> <B>STD-editor</B></div> <div> <A HREF="id58.htm" TARGET="_top" TITLE="FLOWeditors"><U>FLOW-editors</U></A></div> <div> <A HREF="id60.htm" TARGET="_top" TITLE="Expression editors"><U>Expression editors</U></A></div> </tD> </tR> </TABLE></B></div> <bR> </td> <td valign="top" BGCOLOR="#FFFFFF" TEXT="#080000" bgproperties="fixed" background="1ef64643.gif"> <bR> <div> <TABLE BORDER="2" CELLPADDING="2" CELLSPACING="1" WIDTH="666" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" BGCOLOR=#FFFF80 > <tR> <tD VALIGN=TOP HEIGHT= 27 ><NOBR> <SCRIPT language=JavaScript src="menusrc.js"></SCRIPT><SCRIPT language=JavaScript src="menudef.js"></SCRIPT> <SCRIPT language=JavaScript>drawToolbar();</SCRIPT> </NOBR></tD> </tR> </TABLE></div> <bR> <DIV ALIGN="LEFT"></DIV> <div> <TABLE BORDER="5" CELLPADDING="1" CELLSPACING="1" WIDTH="595" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="NONE" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP COLSPAN=2 HEIGHT= 78 ><NOBR><div> <B>State Machines are the central control-objects in your design!</B><FONT SIZE="3" COLOR="#000000" FACE="Arial" > </FONT></div> <div> STDs encapsulate both control and data<FONT SIZE="3" COLOR="#000000" FACE="Arial" >.</FONT></div> <bR> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP COLSPAN=2 HEIGHT= 125 WIDTH="577"><div> An STD can have local <FONT SIZE="2" COLOR="#FF0000" FACE="Arial" ><I>data-members</I></FONT>, <FONT SIZE="2" COLOR="#FF0000" FACE="Arial" ><I>member-functions</I></FONT> and can be <FONT SIZE="2" COLOR="#FF0000" FACE="Arial" ><I>instantiated</I></FONT> multiple times, making them full abstract datatypes similar as "objects", (without inheritance).</div> <div> Transitions normally occur after the flow of the current State has finished execution. However XPad, supports preemptive states as well, immediately allowing execution! These have nothing to do with "threads" or traditional scheduling. They just give you the response time you need when your theoretical one-shot state-flow takes longer than allowed! (And a faster target is not an option).</div> <bR> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 482 WIDTH="121"><bR> <bR> <bR> <div> <I>Every application has idle-times where it is waiting for something to happen! (A key to be pressed, an I/O pin to go low, a time-out to expire, etc.).</I></div> <div> <I>Instead of hoping that a scheduler efficiently manages your idle-time, you will be aware of it at design time and design it "in" explicitly! </I></div> <div> <I>The guideline is: At the end of a state you wait!!!</I></div> <bR> </tD> <tD VALIGN=TOP><NOBR><div> <IMG SRC="274c3dc0.gif" border=0 width="451" height="476" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> </TABLE></div> <bR> <bR> </td> </tr></table></body>