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<TITLE>RE: context switching during delays</TITLE>
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<P><FONT SIZE=2>On a more philosophical note, I need to do short delays in some of my device drivers.</FONT>
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<P><FONT SIZE=2>Say 1/10 of a second.</FONT>
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<P><FONT SIZE=2>What is the appropriate routine to use???</FONT>
<BR><FONT SIZE=2>Should I use a busy/spin loop or should I use something that context switches???</FONT>
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<P><FONT SIZE=2>sleep()</FONT>
<BR><FONT SIZE=2>nanosleep()</FONT>
<BR><FONT SIZE=2>rtems_task_wake_after()</FONT>
<BR><FONT SIZE=2>Something else???</FONT>
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<P><FONT SIZE=2>Thanks,</FONT>
<BR><FONT SIZE=2>Nick</FONT>
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<P><FONT SIZE=2>-----Original Message-----</FONT>
<BR><FONT SIZE=2>From: Joel Sherrill [<A HREF="mailto:joel.sherrill@OARcorp.com">mailto:joel.sherrill@OARcorp.com</A>]</FONT>
<BR><FONT SIZE=2>Sent: Tuesday, July 24, 2001 7:16 PM</FONT>
<BR><FONT SIZE=2>To: Hennenfent, Nick {AVL~Roswell}</FONT>
<BR><FONT SIZE=2>Cc: rtems-users@OARcorp.com</FONT>
<BR><FONT SIZE=2>Subject: Re: context switching during delays</FONT>
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<P><FONT SIZE=2>Hello world does not configure a clock tick device driver</FONT>
<BR><FONT SIZE=2>and thus has no way to measure the passage of time. </FONT>
<BR><FONT SIZE=2>Once you do the context switch, you will end up</FONT>
<BR><FONT SIZE=2>in the idle task with no way to get out of it.</FONT>
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<P><FONT SIZE=2>--</FONT>
<BR><FONT SIZE=2>Joel Sherrill, Ph.D. Director of Research & Development</FONT>
<BR><FONT SIZE=2>joel@OARcorp.com On-Line Applications Research</FONT>
<BR><FONT SIZE=2>Ask me about RTEMS: a free RTOS Huntsville AL 35805</FONT>
<BR><FONT SIZE=2>Support Available (256) 722-9985</FONT>
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