nico@210: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> nico@210: nico@210: <!--Converted with LaTeX2HTML 2002-2-1 (1.71) nico@210: original version by: Nikos Drakos, CBLU, University of Leeds nico@210: * revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan nico@210: * with significant contributions from: nico@210: Jens Lippmann, Marek Rouchal, Martin Wilck and others --> nico@210: <HTML> nico@210: <HEAD> nico@210: <TITLE>CanFestival events scheduling</TITLE> nico@210: <META NAME="description" CONTENT="CanFestival events scheduling"> nico@210: <META NAME="keywords" CONTENT="manual"> nico@210: <META NAME="resource-type" CONTENT="document"> nico@210: <META NAME="distribution" CONTENT="global"> nico@210: nico@210: <META NAME="Generator" CONTENT="LaTeX2HTML v2002-2-1"> nico@210: <META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css"> nico@210: nico@210: <LINK REL="STYLESHEET" HREF="manual.css"> nico@210: nico@210: <LINK REL="previous" HREF="node19.html"> nico@210: <LINK REL="up" HREF="node16.html"> nico@210: <LINK REL="next" HREF="node21.html"> nico@210: </HEAD> nico@210: nico@210: <BODY > nico@210: nico@210: <DIV CLASS="navigation"><!--Navigation Panel--> nico@210: <A NAME="tex2html394" nico@210: HREF="node21.html"> nico@210: <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" nico@210: SRC="/usr/share/latex2html/icons/next.png"></A> nico@210: <A NAME="tex2html390" nico@210: HREF="node16.html"> nico@210: <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" nico@210: SRC="/usr/share/latex2html/icons/up.png"></A> nico@210: <A NAME="tex2html386" nico@210: HREF="node19.html"> nico@210: <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" nico@210: SRC="/usr/share/latex2html/icons/prev.png"></A> nico@210: <A NAME="tex2html392" nico@210: HREF="node1.html"> nico@210: <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" nico@210: SRC="/usr/share/latex2html/icons/contents.png"></A> nico@210: <BR> nico@210: <B> Next:</B> <A NAME="tex2html395" nico@210: HREF="node21.html">Linux Target</A> nico@210: <B> Up:</B> <A NAME="tex2html391" nico@210: HREF="node16.html">Understanding Canfestival</A> nico@210: <B> Previous:</B> <A NAME="tex2html387" nico@210: HREF="node19.html">CanFestival CAN interfaces</A> nico@210: <B> <A NAME="tex2html393" nico@210: HREF="node1.html">Contents</A></B> nico@210: <BR> nico@210: <BR></DIV> nico@210: <!--End of Navigation Panel--> nico@210: nico@210: <H2><A NAME="SECTION00054000000000000000"> nico@210: CanFestival events scheduling</A> nico@210: </H2> nico@210: A CanOpen node must be able to take delayed actions. nico@210: nico@210: <P> nico@210: As exemples, periodic sync emission, heartbeat production or SDO timeout nico@210: need to set some alarms that will be called later and do the job. nico@210: nico@210: <P> nico@210: µC generaly do not have enough free timers to handle all the nico@210: CanOpen needs directly. Moreover, CanFestival internal data may be nico@210: corrupt by reentrant calls. nico@210: nico@210: <P> nico@210: CanFestival implement a micro-scheduler (timer.c). It uses only one nico@210: timer to mimic many timers. It manage an alarm table, and call alarms nico@210: at desired time. nico@210: nico@210: <P> nico@210: <DIV ALIGN="CENTER"> nico@210: <IMG nico@211: WIDTH="512" HEIGHT="205" ALIGN="BOTTOM" BORDER="0" nico@210: SRC="./100000000000022C000000DEDAD2140C.png" nico@210: ALT="Image 100000000000022C000000DEDAD2140C"> nico@210: nico@210: </DIV> nico@210: nico@210: <P> nico@210: Scheduler can handle short clock value ranges limitation found on some nico@210: µC. As an example, value range for a 16bit clock counter with nico@210: 4µs tick is crossed within 0.26 seconds... Long alarms must be nico@210: segmented. nico@210: nico@210: <P> nico@210: Chronogram illustrate a long alarm (A) and a short periodic alarm (B), nico@210: with a A value > clock range > B value. nico@210: Values t0...t8 are successive setTimer call parameter values. t1 nico@210: illustrates an intermediate call to TimeDispatch, caused by a delay nico@210: longer than clock range. Because of long alarm segmentation, at the end nico@210: of t1, TimeDispatch call will not trig any alarm callback. nico@210: nico@210: <P> nico@210: <DIV ALIGN="CENTER"> nico@210: <IMG nico@211: WIDTH="709" HEIGHT="197" ALIGN="BOTTOM" BORDER="0" nico@210: SRC="./1000000000000396000000FFC42573DA.png" nico@210: ALT="Image 1000000000000396000000FFC42573DA"> nico@210: nico@210: </DIV> nico@210: nico@210: <P> nico@210: nico@210: <DIV CLASS="navigation"><HR> nico@210: <!--Navigation Panel--> nico@210: <A NAME="tex2html394" nico@210: HREF="node21.html"> nico@210: <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" nico@210: SRC="/usr/share/latex2html/icons/next.png"></A> nico@210: <A NAME="tex2html390" nico@210: HREF="node16.html"> nico@210: <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" nico@210: SRC="/usr/share/latex2html/icons/up.png"></A> nico@210: <A NAME="tex2html386" nico@210: HREF="node19.html"> nico@210: <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" nico@210: SRC="/usr/share/latex2html/icons/prev.png"></A> nico@210: <A NAME="tex2html392" nico@210: HREF="node1.html"> nico@210: <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" nico@210: SRC="/usr/share/latex2html/icons/contents.png"></A> nico@210: <BR> nico@210: <B> Next:</B> <A NAME="tex2html395" nico@210: HREF="node21.html">Linux Target</A> nico@210: <B> Up:</B> <A NAME="tex2html391" nico@210: HREF="node16.html">Understanding Canfestival</A> nico@210: <B> Previous:</B> <A NAME="tex2html387" nico@210: HREF="node19.html">CanFestival CAN interfaces</A> nico@210: <B> <A NAME="tex2html393" nico@210: HREF="node1.html">Contents</A></B> </DIV> nico@210: <!--End of Navigation Panel--> nico@210: <ADDRESS> nico@210: epimerde nico@215: 2007-06-08 nico@210: </ADDRESS> nico@210: </BODY> nico@210: </HTML>