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<HTML
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><HEAD
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><TITLE
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>µITRON Configuration FAQ</TITLE
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"><LINK
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REL="HOME"
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TITLE="eCos Reference Manual"
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HREF="ecos-ref.html"><LINK
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REL="UP"
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TITLE="µITRON API"
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HREF="compat-uitron-microitron-api.html"><LINK
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REL="PREVIOUS"
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TITLE=" Network Support Functions"
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HREF="compat-uitron-network-support-functions.html"><LINK
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REL="NEXT"
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TITLE="TCP/IP Stack Support for eCos"
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HREF="net-common-tcpip.html"></HEAD
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><BODY
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>eCos Reference Manual</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="compat-uitron-network-support-functions.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 32. µITRON API</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="net-common-tcpip.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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><H1
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CLASS="SECT1"
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><A
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NAME="COMPAT-UITRON-CONFIGURATION-FAQ">µITRON Configuration FAQ</H1
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><P
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><SPAN
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CLASS="emphasis"
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><I
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CLASS="EMPHASIS"
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>Q: How are µITRON objects created?</I
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></SPAN
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></P
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><P
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>For each type of uITRON object (tasks, semaphores, flags, mboxes, mpf, mpl)
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these two quantities are controlled by configuration:</P
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><P
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></P
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><UL
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><LI
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><P
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>The <SPAN
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CLASS="emphasis"
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><I
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CLASS="EMPHASIS"
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>maximum</I
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></SPAN
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> number of this type of object.</P
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></LI
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><LI
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><P
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>The number of these objects which exist <SPAN
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CLASS="emphasis"
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><I
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CLASS="EMPHASIS"
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>initially</I
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></SPAN
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>.</P
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></LI
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></UL
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><P
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>This is assuming that for the relevant object type,
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<SPAN
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CLASS="emphasis"
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><I
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CLASS="EMPHASIS"
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>create</I
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></SPAN
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> and <SPAN
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CLASS="emphasis"
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><I
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CLASS="EMPHASIS"
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>delete</I
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></SPAN
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>
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operations are enabled; enabled is the default. For example, the option
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<TT
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CLASS="LITERAL"
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>CYGPKG_UITRON_MBOXES_CREATE_DELETE</TT
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>
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controls whether the functions
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<TT
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CLASS="FUNCTION"
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>cre_mbx()</TT
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>
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and
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<TT
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CLASS="FUNCTION"
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>del_mbx()</TT
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>
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exist in the API. If not, then the maximum number of
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mboxes is the same as the initial number of mboxes, and so on for all
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µITRON object types.</P
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><P
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>Mboxes have no initialization, so there are only a few, simple
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configuration options:</P
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><P
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></P
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><UL
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><LI
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><P
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><TT
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CLASS="LITERAL"
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>CYGNUM_UITRON_MBOXES</TT
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>
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is the total number of mboxes that you can have in the
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system. By default this is 4, so you can use mboxes 1,2,3 and 4. You
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cannot create mboxes outside this range; trying to
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<TT
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CLASS="FUNCTION"
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>cre_mbx(5,...)</TT
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>
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will return an error.</P
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></LI
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><LI
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><P
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><TT
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CLASS="LITERAL"
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>CYGNUM_UITRON_MBOXES_INITIALLY</TT
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>
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is the number of mboxes created
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automatically for you, during startup. By default this is 4, so all 4
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mboxes exist already, and an attempt to create one of these
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eg. <TT
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CLASS="FUNCTION"
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>cre_mbx(3,...)</TT
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>
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will return an error because the mbox in quesion already
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exists. You can delete a pre-existing mbox, and then re-create it.</P
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></LI
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></UL
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><P
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>If you change
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<TT
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CLASS="LITERAL"
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>CYGNUM_UITRON_MBOXES_INITIALLY</TT
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>,
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for example to 0, no mboxes
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are created automatically for you during startup. Any attempt to use an
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mbox without creating it will return E_NOEXS because the mbox does not
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exist. You can create an mbox, say <TT
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CLASS="FUNCTION"
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>cre_mbx(3,...)</TT
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>
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and then use it, say
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<TT
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CLASS="FUNCTION"
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>snd_msg(3,&foo)</TT
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>, and all will be well.</P
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><P
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><SPAN
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CLASS="emphasis"
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><I
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CLASS="EMPHASIS"
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>Q: How are µITRON objects initialized?</I
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></SPAN
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></P
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><P
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>Some object types have optional initialization. Semaphores are an
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example. You could have
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<TT
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CLASS="LITERAL"
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>CYGNUM_UITRON_SEMAS</TT
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>=10 and
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<TT
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CLASS="LITERAL"
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>CYGNUM_UITRON_SEMAS_INITIALLY</TT
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>=5
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which means you can use semaphores 1-5
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straight off, but you must create semaphores 6-10 before you can use them.
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If you decide not to initialize semaphores, semaphores 1-5 will have an
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initial count of zero. If you decide to initialize them, you must supply
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a dummy initializer for semaphores 6-10 also. For example,
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in terms of the configuration output in
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<TT
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CLASS="FILENAME"
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>pkgconf/uitron.h</TT
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>:</P
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><TABLE
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BORDER="5"
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BGCOLOR="#E0E0F0"
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WIDTH="70%"
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><TR
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><TD
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><PRE
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CLASS="PROGRAMLISTING"
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> #define CYGDAT_UITRON_SEMA_INITIALIZERS \
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CYG_UIT_SEMA( 1 ), \
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CYG_UIT_SEMA( 0 ), \
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CYG_UIT_SEMA( 0 ), \
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CYG_UIT_SEMA( 99 ), \
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CYG_UIT_SEMA( 1 ), \
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CYG_UIT_SEMA_NOEXS, \
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CYG_UIT_SEMA_NOEXS, \
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CYG_UIT_SEMA_NOEXS, \
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CYG_UIT_SEMA_NOEXS, \
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CYG_UIT_SEMA_NOEXS</PRE
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></TD
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></TR
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></TABLE
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><P
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>Semaphore 1 will have initial count 1, semaphores 2 and 3 will be zero,
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number 4 will be 99 initially, 5 will be one and numbers 6 though 10 do not
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exist initially.</P
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><P
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>Aside: this is how the definition of the symbol would appear in the
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configuration header file <TT
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CLASS="FILENAME"
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>pkgconf/uitron.h</TT
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> —
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unfortunately editing such a long, multi-line definition is somewhat
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cumbersome in the GUI config tool in current releases. The macros
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<TT
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CLASS="LITERAL"
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>CYG_UIT_SEMA()</TT
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>
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— to create a semaphore initializer — and
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<TT
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CLASS="LITERAL"
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>CYG_UIT_SEMA_NOEXS</TT
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>
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— to invoke a dummy initializer —
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are provided in in the environment to help with this. Similar macros are
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provided for other object types. The resulting #define symbol is used in
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the context of a C++ array initializer, such as:
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<TABLE
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BORDER="5"
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BGCOLOR="#E0E0F0"
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WIDTH="70%"
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><TR
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><TD
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><PRE
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CLASS="PROGRAMLISTING"
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>Cyg_Counting_Semaphore2 cyg_uitron_SEMAS[ CYGNUM_UITRON_SEMAS ] = {
|
| 295 |
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CYGDAT_UITRON_SEMA_INITIALIZERS
|
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};</PRE
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></TD
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></TR
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></TABLE
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>
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which is eventually macro-processed to give
|
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<TABLE
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BORDER="5"
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BGCOLOR="#E0E0F0"
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WIDTH="70%"
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><TR
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><TD
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><PRE
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CLASS="PROGRAMLISTING"
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| 310 |
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>Cyg_Counting_Semaphore2 cyg_uitron_SEMAS[ 10 ] = {
|
| 311 |
|
|
Cyg_Counting_Semaphore2( ( 1 ) ),
|
| 312 |
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Cyg_Counting_Semaphore2( ( 0 ) ),
|
| 313 |
|
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Cyg_Counting_Semaphore2( ( 0 ) ),
|
| 314 |
|
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Cyg_Counting_Semaphore2( ( 99 ) ),
|
| 315 |
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Cyg_Counting_Semaphore2( ( 1 ) ),
|
| 316 |
|
|
Cyg_Counting_Semaphore2(0),
|
| 317 |
|
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Cyg_Counting_Semaphore2(0),
|
| 318 |
|
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Cyg_Counting_Semaphore2(0),
|
| 319 |
|
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Cyg_Counting_Semaphore2(0),
|
| 320 |
|
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Cyg_Counting_Semaphore2(0),
|
| 321 |
|
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};</PRE
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></TD
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></TR
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></TABLE
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>
|
| 326 |
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|
so you can see how it is necessary to include the dummy entries in that
|
| 327 |
|
|
definition, otherwise the resulting code will not compile correctly.</P
|
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><P
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>If you choose
|
| 330 |
|
|
<TT
|
| 331 |
|
|
CLASS="LITERAL"
|
| 332 |
|
|
>CYGNUM_UITRON_SEMAS_INITIALLY</TT
|
| 333 |
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|
>=0
|
| 334 |
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it is meaningless to initialize them, for they must be created and so
|
| 335 |
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initialized then, before use.</P
|
| 336 |
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><P
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| 337 |
|
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><SPAN
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CLASS="emphasis"
|
| 339 |
|
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><I
|
| 340 |
|
|
CLASS="EMPHASIS"
|
| 341 |
|
|
>Q: What about µITRON tasks?</I
|
| 342 |
|
|
></SPAN
|
| 343 |
|
|
></P
|
| 344 |
|
|
><P
|
| 345 |
|
|
>Some object types require initialization. Tasks are an example of this.
|
| 346 |
|
|
You must provide a task with a priority, a function to enter when the task
|
| 347 |
|
|
starts, a name (for debugging purposes), and some memory to use for the stack.
|
| 348 |
|
|
For example (again in terms of the resulting
|
| 349 |
|
|
definitions in <TT
|
| 350 |
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CLASS="FILENAME"
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>pkgconf/uitron.h</TT
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>):</P
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><TABLE
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BORDER="5"
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BGCOLOR="#E0E0F0"
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WIDTH="70%"
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><TR
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><TD
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><PRE
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CLASS="PROGRAMLISTING"
|
| 361 |
|
|
>#define CYGNUM_UITRON_TASKS 4 // valid task ids are 1,2,3,4
|
| 362 |
|
|
#define CYGNUM_UITRON_TASKS_INITIALLY 4 // they all exist at start
|
| 363 |
|
|
|
| 364 |
|
|
#define CYGDAT_UITRON_TASK_EXTERNS \
|
| 365 |
|
|
extern "C" void startup( unsigned int ); \
|
| 366 |
|
|
extern "C" void worktask( unsigned int ); \
|
| 367 |
|
|
extern "C" void lowtask( unsigned int ); \
|
| 368 |
|
|
static char stack1[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 369 |
|
|
stack2[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 370 |
|
|
stack3[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 371 |
|
|
stack4[ CYGNUM_UITRON_STACK_SIZE ];
|
| 372 |
|
|
|
| 373 |
|
|
#define CYGDAT_UITRON_TASK_INITIALIZERS \
|
| 374 |
|
|
CYG_UIT_TASK("main task", 8, startup, &stack1, sizeof( stack1 )), \
|
| 375 |
|
|
CYG_UIT_TASK("worker 2" , 9, worktask, &stack2, sizeof( stack2 )), \
|
| 376 |
|
|
CYG_UIT_TASK("worker 3" , 9, worktask, &stack3, sizeof( stack3 )), \
|
| 377 |
|
|
CYG_UIT_TASK("low task" ,20, lowtask, &stack4, sizeof( stack4 )), \ </PRE
|
| 378 |
|
|
></TD
|
| 379 |
|
|
></TR
|
| 380 |
|
|
></TABLE
|
| 381 |
|
|
><P
|
| 382 |
|
|
>So this example has all four tasks statically configured to exist, ready to
|
| 383 |
|
|
run, from the start of time. The “main task” runs a routine
|
| 384 |
|
|
called <TT
|
| 385 |
|
|
CLASS="FUNCTION"
|
| 386 |
|
|
>startup()</TT
|
| 387 |
|
|
> at priority 8. Two
|
| 388 |
|
|
“worker” tasks run both a priority 9, and a “low
|
| 389 |
|
|
priority” task runs at priority 20 to do useful non-urgent background
|
| 390 |
|
|
work.</P
|
| 391 |
|
|
><TABLE
|
| 392 |
|
|
BORDER="5"
|
| 393 |
|
|
BGCOLOR="#E0E0F0"
|
| 394 |
|
|
WIDTH="70%"
|
| 395 |
|
|
><TR
|
| 396 |
|
|
><TD
|
| 397 |
|
|
><PRE
|
| 398 |
|
|
CLASS="SCREEN"
|
| 399 |
|
|
>Task ID | Exists at | Function | Priority | Stack | Stack
|
| 400 |
|
|
number | startup | entry | | address | size
|
| 401 |
|
|
--------+-----------+----------+----------+---------+----------
|
| 402 |
|
|
1 | Yes | startup | 8 | &stack1 | CYGNUM...
|
| 403 |
|
|
2 | Yes | worktask | 9 | &stack2 | CYGNUM...
|
| 404 |
|
|
3 | Yes | worktask | 9 | &stack3 | CYGNUM...
|
| 405 |
|
|
4 | Yes | lowtask | 20 | &stack4 | CYGNUM...
|
| 406 |
|
|
--------+-----------+----------+----------+---------+----------</PRE
|
| 407 |
|
|
></TD
|
| 408 |
|
|
></TR
|
| 409 |
|
|
></TABLE
|
| 410 |
|
|
><P
|
| 411 |
|
|
><SPAN
|
| 412 |
|
|
CLASS="emphasis"
|
| 413 |
|
|
><I
|
| 414 |
|
|
CLASS="EMPHASIS"
|
| 415 |
|
|
>Q: How can I create µITRON tasks in the program?</I
|
| 416 |
|
|
></SPAN
|
| 417 |
|
|
></P
|
| 418 |
|
|
><P
|
| 419 |
|
|
>You must provide free slots in the task table in which to create new tasks,
|
| 420 |
|
|
by configuring the number of tasks existing initially to be smaller than
|
| 421 |
|
|
the total.
|
| 422 |
|
|
For a task ID which does not initially exist, it will be told what routine
|
| 423 |
|
|
to call, and what priority it is, when the task is created. But you must
|
| 424 |
|
|
still set aside memory for the task to use for its stack, and give it a
|
| 425 |
|
|
name during initialization. For example:</P
|
| 426 |
|
|
><TABLE
|
| 427 |
|
|
BORDER="5"
|
| 428 |
|
|
BGCOLOR="#E0E0F0"
|
| 429 |
|
|
WIDTH="70%"
|
| 430 |
|
|
><TR
|
| 431 |
|
|
><TD
|
| 432 |
|
|
><PRE
|
| 433 |
|
|
CLASS="PROGRAMLISTING"
|
| 434 |
|
|
>#define CYGNUM_UITRON_TASKS 4 // valid task ids are 1-4
|
| 435 |
|
|
#define CYGNUM_UITRON_TASKS_INITIALLY 1 // only task #1 exists
|
| 436 |
|
|
|
| 437 |
|
|
#define CYGDAT_UITRON_TASK_EXTERNS \
|
| 438 |
|
|
extern "C" void startup( unsigned int ); \
|
| 439 |
|
|
static char stack1[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 440 |
|
|
stack2[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 441 |
|
|
stack3[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 442 |
|
|
stack4[ CYGNUM_UITRON_STACK_SIZE ];
|
| 443 |
|
|
|
| 444 |
|
|
#define CYGDAT_UITRON_TASK_INITIALIZERS \
|
| 445 |
|
|
CYG_UIT_TASK( "main", 8, startup, &stack1, sizeof( stack1 ) ), \
|
| 446 |
|
|
CYG_UIT_TASK_NOEXS( "slave", &stack2, sizeof( stack2 ) ), \
|
| 447 |
|
|
CYG_UIT_TASK_NOEXS( "slave2", &stack3, sizeof( stack3 ) ), \
|
| 448 |
|
|
CYG_UIT_TASK_NOEXS( "slave3", &stack4, sizeof( stack4 ) ), \ </PRE
|
| 449 |
|
|
></TD
|
| 450 |
|
|
></TR
|
| 451 |
|
|
></TABLE
|
| 452 |
|
|
><P
|
| 453 |
|
|
>So tasks numbered 2,3 and 4 have been given their stacks during startup,
|
| 454 |
|
|
though they do not yet exist in terms of <TT
|
| 455 |
|
|
CLASS="FUNCTION"
|
| 456 |
|
|
>cre_tsk()</TT
|
| 457 |
|
|
> and
|
| 458 |
|
|
<TT
|
| 459 |
|
|
CLASS="FUNCTION"
|
| 460 |
|
|
>del_tsk()</TT
|
| 461 |
|
|
> so you can create tasks 2–4 at
|
| 462 |
|
|
runtime.</P
|
| 463 |
|
|
><TABLE
|
| 464 |
|
|
BORDER="5"
|
| 465 |
|
|
BGCOLOR="#E0E0F0"
|
| 466 |
|
|
WIDTH="70%"
|
| 467 |
|
|
><TR
|
| 468 |
|
|
><TD
|
| 469 |
|
|
><PRE
|
| 470 |
|
|
CLASS="SCREEN"
|
| 471 |
|
|
>Task ID | Exists at | Function | Priority | Stack | Stack
|
| 472 |
|
|
number | startup | entry | | address | size
|
| 473 |
|
|
--------+-----------+----------+----------+---------+----------
|
| 474 |
|
|
1 | Yes | startup | 8 | &stack1 | CYGNUM...
|
| 475 |
|
|
2 | No | N/A | N/A | &stack2 | CYGNUM...
|
| 476 |
|
|
3 | No | N/A | N/A | &stack3 | CYGNUM...
|
| 477 |
|
|
4 | No | N/A | N/A | &stack4 | CYGNUM...
|
| 478 |
|
|
--------+-----------+----------+----------+---------+----------</PRE
|
| 479 |
|
|
></TD
|
| 480 |
|
|
></TR
|
| 481 |
|
|
></TABLE
|
| 482 |
|
|
><P
|
| 483 |
|
|
>(you must have at least one task at startup in order that the system can
|
| 484 |
|
|
actually run; this is not so for other uITRON object types)</P
|
| 485 |
|
|
><P
|
| 486 |
|
|
><SPAN
|
| 487 |
|
|
CLASS="emphasis"
|
| 488 |
|
|
><I
|
| 489 |
|
|
CLASS="EMPHASIS"
|
| 490 |
|
|
>Q: Can I have different stack sizes for µITRON tasks?</I
|
| 491 |
|
|
></SPAN
|
| 492 |
|
|
></P
|
| 493 |
|
|
><P
|
| 494 |
|
|
>Simply set aside different amounts of memory for each task to use for its
|
| 495 |
|
|
stack. Going back to a typical default setting for the µITRON tasks,
|
| 496 |
|
|
the definitions in <TT
|
| 497 |
|
|
CLASS="FILENAME"
|
| 498 |
|
|
>pkgconf/uitron.h</TT
|
| 499 |
|
|
> might look like this:</P
|
| 500 |
|
|
><TABLE
|
| 501 |
|
|
BORDER="5"
|
| 502 |
|
|
BGCOLOR="#E0E0F0"
|
| 503 |
|
|
WIDTH="70%"
|
| 504 |
|
|
><TR
|
| 505 |
|
|
><TD
|
| 506 |
|
|
><PRE
|
| 507 |
|
|
CLASS="PROGRAMLISTING"
|
| 508 |
|
|
>#define CYGDAT_UITRON_TASK_EXTERNS \
|
| 509 |
|
|
extern "C" void task1( unsigned int ); \
|
| 510 |
|
|
extern "C" void task2( unsigned int ); \
|
| 511 |
|
|
extern "C" void task3( unsigned int ); \
|
| 512 |
|
|
extern "C" void task4( unsigned int ); \
|
| 513 |
|
|
static char stack1[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 514 |
|
|
stack2[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 515 |
|
|
stack3[ CYGNUM_UITRON_STACK_SIZE ], \
|
| 516 |
|
|
stack4[ CYGNUM_UITRON_STACK_SIZE ];
|
| 517 |
|
|
|
| 518 |
|
|
#define CYGDAT_UITRON_TASK_INITIALIZERS \
|
| 519 |
|
|
CYG_UIT_TASK( "t1", 1, task1, &stack1, CYGNUM_UITRON_STACK_SIZE ), \
|
| 520 |
|
|
CYG_UIT_TASK( "t2", 2, task2, &stack2, CYGNUM_UITRON_STACK_SIZE ), \
|
| 521 |
|
|
CYG_UIT_TASK( "t3", 3, task3, &stack3, CYGNUM_UITRON_STACK_SIZE ), \
|
| 522 |
|
|
CYG_UIT_TASK( "t4", 4, task4, &stack4, CYGNUM_UITRON_STACK_SIZE ) </PRE
|
| 523 |
|
|
></TD
|
| 524 |
|
|
></TR
|
| 525 |
|
|
></TABLE
|
| 526 |
|
|
><P
|
| 527 |
|
|
>Note that
|
| 528 |
|
|
<TT
|
| 529 |
|
|
CLASS="LITERAL"
|
| 530 |
|
|
>CYGNUM_UITRON_STACK_SIZE</TT
|
| 531 |
|
|
>
|
| 532 |
|
|
is used to control the size of the stack
|
| 533 |
|
|
objects themselves, and to tell the system what size stack is being provided.</P
|
| 534 |
|
|
><P
|
| 535 |
|
|
>Suppose instead stack sizes of 2000, 1000, 800 and 800 were required:
|
| 536 |
|
|
this could be achieved by using the GUI config tool to edit these
|
| 537 |
|
|
options, or editting the <TT
|
| 538 |
|
|
CLASS="FILENAME"
|
| 539 |
|
|
>.ecc</TT
|
| 540 |
|
|
> file to get these
|
| 541 |
|
|
results in <TT
|
| 542 |
|
|
CLASS="FILENAME"
|
| 543 |
|
|
>pkgconf/uitron.h</TT
|
| 544 |
|
|
>:</P
|
| 545 |
|
|
><TABLE
|
| 546 |
|
|
BORDER="5"
|
| 547 |
|
|
BGCOLOR="#E0E0F0"
|
| 548 |
|
|
WIDTH="70%"
|
| 549 |
|
|
><TR
|
| 550 |
|
|
><TD
|
| 551 |
|
|
><PRE
|
| 552 |
|
|
CLASS="PROGRAMLISTING"
|
| 553 |
|
|
>#define CYGDAT_UITRON_TASK_EXTERNS \
|
| 554 |
|
|
extern "C" void task1( unsigned int ); \
|
| 555 |
|
|
extern "C" void task2( unsigned int ); \
|
| 556 |
|
|
extern "C" void task3( unsigned int ); \
|
| 557 |
|
|
extern "C" void task4( unsigned int ); \
|
| 558 |
|
|
static char stack1[ 2000 ], \
|
| 559 |
|
|
stack2[ 1000 ], \
|
| 560 |
|
|
stack3[ 800 ], \
|
| 561 |
|
|
stack4[ 800 ];
|
| 562 |
|
|
|
| 563 |
|
|
#define CYGDAT_UITRON_TASK_INITIALIZERS \
|
| 564 |
|
|
CYG_UIT_TASK( "t1", 1, task1, &stack1, sizeof( stack1 ) ), \
|
| 565 |
|
|
CYG_UIT_TASK( "t2", 2, task2, &stack2, sizeof( stack2 ) ), \
|
| 566 |
|
|
CYG_UIT_TASK( "t3", 3, task3, &stack3, sizeof( stack3 ) ), \
|
| 567 |
|
|
CYG_UIT_TASK( "t4", 4, task4, &stack4, sizeof( stack4 ) )</PRE
|
| 568 |
|
|
></TD
|
| 569 |
|
|
></TR
|
| 570 |
|
|
></TABLE
|
| 571 |
|
|
><P
|
| 572 |
|
|
>Note that the sizeof() operator has been used to tell the system what size
|
| 573 |
|
|
stacks are provided, rather than quoting a number (which is difficult for
|
| 574 |
|
|
maintenance) or the symbol
|
| 575 |
|
|
<TT
|
| 576 |
|
|
CLASS="LITERAL"
|
| 577 |
|
|
>CYGNUM_UITRON_STACK_SIZE</TT
|
| 578 |
|
|
>
|
| 579 |
|
|
(which is wrong).</P
|
| 580 |
|
|
><P
|
| 581 |
|
|
>We recommend using (if available in your release) the stacksize symbols
|
| 582 |
|
|
provided in the architectural HAL for your target, called
|
| 583 |
|
|
<TT
|
| 584 |
|
|
CLASS="LITERAL"
|
| 585 |
|
|
>CYGNUM_HAL_STACK_SIZE_TYPICAL</TT
|
| 586 |
|
|
>
|
| 587 |
|
|
and
|
| 588 |
|
|
<TT
|
| 589 |
|
|
CLASS="LITERAL"
|
| 590 |
|
|
>CYGNUM_HAL_STACK_SIZE_MINIMUM</TT
|
| 591 |
|
|
>.
|
| 592 |
|
|
So a better (more portable) version of the above might be:</P
|
| 593 |
|
|
><TABLE
|
| 594 |
|
|
BORDER="5"
|
| 595 |
|
|
BGCOLOR="#E0E0F0"
|
| 596 |
|
|
WIDTH="70%"
|
| 597 |
|
|
><TR
|
| 598 |
|
|
><TD
|
| 599 |
|
|
><PRE
|
| 600 |
|
|
CLASS="PROGRAMLISTING"
|
| 601 |
|
|
>#define CYGDAT_UITRON_TASK_EXTERNS \
|
| 602 |
|
|
extern "C" void task1( unsigned int ); \
|
| 603 |
|
|
extern "C" void task2( unsigned int ); \
|
| 604 |
|
|
extern "C" void task3( unsigned int ); \
|
| 605 |
|
|
extern "C" void task4( unsigned int ); \
|
| 606 |
|
|
static char stack1[ CYGNUM_HAL_STACK_SIZE_TYPICAL + 1200 ], \
|
| 607 |
|
|
stack2[ CYGNUM_HAL_STACK_SIZE_TYPICAL + 200 ], \
|
| 608 |
|
|
stack3[ CYGNUM_HAL_STACK_SIZE_TYPICAL ], \
|
| 609 |
|
|
stack4[ CYGNUM_HAL_STACK_SIZE_TYPICAL ];
|
| 610 |
|
|
|
| 611 |
|
|
#define CYGDAT_UITRON_TASK_INITIALIZERS \
|
| 612 |
|
|
CYG_UIT_TASK( "t1", 1, task1, &stack1, sizeof( stack1 ) ), \
|
| 613 |
|
|
CYG_UIT_TASK( "t2", 2, task2, &stack2, sizeof( stack2 ) ), \
|
| 614 |
|
|
CYG_UIT_TASK( "t3", 3, task3, &stack3, sizeof( stack3 ) ), \
|
| 615 |
|
|
CYG_UIT_TASK( "t4", 4, task4, &stack4, sizeof( stack4 ) )</PRE
|
| 616 |
|
|
></TD
|
| 617 |
|
|
></TR
|
| 618 |
|
|
></TABLE
|
| 619 |
|
|
></DIV
|
| 620 |
|
|
><DIV
|
| 621 |
|
|
CLASS="NAVFOOTER"
|
| 622 |
|
|
><HR
|
| 623 |
|
|
ALIGN="LEFT"
|
| 624 |
|
|
WIDTH="100%"><TABLE
|
| 625 |
|
|
SUMMARY="Footer navigation table"
|
| 626 |
|
|
WIDTH="100%"
|
| 627 |
|
|
BORDER="0"
|
| 628 |
|
|
CELLPADDING="0"
|
| 629 |
|
|
CELLSPACING="0"
|
| 630 |
|
|
><TR
|
| 631 |
|
|
><TD
|
| 632 |
|
|
WIDTH="33%"
|
| 633 |
|
|
ALIGN="left"
|
| 634 |
|
|
VALIGN="top"
|
| 635 |
|
|
><A
|
| 636 |
|
|
HREF="compat-uitron-network-support-functions.html"
|
| 637 |
|
|
ACCESSKEY="P"
|
| 638 |
|
|
>Prev</A
|
| 639 |
|
|
></TD
|
| 640 |
|
|
><TD
|
| 641 |
|
|
WIDTH="34%"
|
| 642 |
|
|
ALIGN="center"
|
| 643 |
|
|
VALIGN="top"
|
| 644 |
|
|
><A
|
| 645 |
|
|
HREF="ecos-ref.html"
|
| 646 |
|
|
ACCESSKEY="H"
|
| 647 |
|
|
>Home</A
|
| 648 |
|
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></TD
|
| 649 |
|
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><TD
|
| 650 |
|
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WIDTH="33%"
|
| 651 |
|
|
ALIGN="right"
|
| 652 |
|
|
VALIGN="top"
|
| 653 |
|
|
><A
|
| 654 |
|
|
HREF="net-common-tcpip.html"
|
| 655 |
|
|
ACCESSKEY="N"
|
| 656 |
|
|
>Next</A
|
| 657 |
|
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></TD
|
| 658 |
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></TR
|
| 659 |
|
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><TR
|
| 660 |
|
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><TD
|
| 661 |
|
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WIDTH="33%"
|
| 662 |
|
|
ALIGN="left"
|
| 663 |
|
|
VALIGN="top"
|
| 664 |
|
|
>Network Support Functions</TD
|
| 665 |
|
|
><TD
|
| 666 |
|
|
WIDTH="34%"
|
| 667 |
|
|
ALIGN="center"
|
| 668 |
|
|
VALIGN="top"
|
| 669 |
|
|
><A
|
| 670 |
|
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HREF="compat-uitron-microitron-api.html"
|
| 671 |
|
|
ACCESSKEY="U"
|
| 672 |
|
|
>Up</A
|
| 673 |
|
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></TD
|
| 674 |
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><TD
|
| 675 |
|
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WIDTH="33%"
|
| 676 |
|
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ALIGN="right"
|
| 677 |
|
|
VALIGN="top"
|
| 678 |
|
|
>TCP/IP Stack Support for eCos</TD
|
| 679 |
|
|
></TR
|
| 680 |
|
|
></TABLE
|
| 681 |
|
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></DIV
|
| 682 |
|
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></BODY
|
| 683 |
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></HTML
|
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>
|