+++ /dev/null
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-<HTML
-><HEAD
-><TITLE
->Starting up a USB Device</TITLE
-><meta name="MSSmartTagsPreventParsing" content="TRUE">
-<META
-NAME="GENERATOR"
-CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
-"><LINK
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-TITLE="eCos Reference Manual"
-HREF="ecos-ref.html"><LINK
-REL="UP"
-TITLE="eCos USB Slave Support"
-HREF="io-usb-slave.html"><LINK
-REL="PREVIOUS"
-TITLE="USB Enumeration Data"
-HREF="usbs-enum.html"><LINK
-REL="NEXT"
-TITLE="Devtab Entries"
-HREF="usbs-devtab.html"></HEAD
-><BODY
-CLASS="REFENTRY"
-BGCOLOR="#FFFFFF"
-TEXT="#000000"
-LINK="#0000FF"
-VLINK="#840084"
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-><DIV
-CLASS="NAVHEADER"
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->Next</A
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-><HR
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-WIDTH="100%"></DIV
-><H1
-><A
-NAME="USBS-START">Starting up a USB Device</H1
-><DIV
-CLASS="REFNAMEDIV"
-><A
-NAME="AEN16210"
-></A
-><H2
->Name</H2
-><TT
-CLASS="FUNCTION"
->usbs_start</TT
-> -- Starting up a USB Device</DIV
-><DIV
-CLASS="REFSYNOPSISDIV"
-><A
-NAME="AEN16214"><H2
->Synopsis</H2
-><DIV
-CLASS="FUNCSYNOPSIS"
-><A
-NAME="AEN16215"><P
-></P
-><TABLE
-BORDER="5"
-BGCOLOR="#E0E0F0"
-WIDTH="70%"
-><TR
-><TD
-><PRE
-CLASS="FUNCSYNOPSISINFO"
->#include <cyg/io/usb/usbs.h></PRE
-></TD
-></TR
-></TABLE
-><P
-><CODE
-><CODE
-CLASS="FUNCDEF"
->void usbs_start</CODE
->(usbs_control_endpoint* ep0);</CODE
-></P
-><P
-></P
-></DIV
-></DIV
-><DIV
-CLASS="REFSECT1"
-><A
-NAME="AEN16222"
-></A
-><H2
->Description</H2
-><P
->Initializing a USB device requires some support from higher-level
-code, typically the application, in the form of enumeration data.
-Hence it is not possible for the low-level USB driver to activate a
-USB device itself. Instead the higher-level code has to take care of
-this by invoking <TT
-CLASS="FUNCTION"
->usbs_start</TT
->. This function takes
-a pointer to a USB control endpoint data structure. USB device drivers
-should provide exactly one such data structure for every USB device,
-so the pointer uniquely identifies the device.</P
-><TABLE
-BORDER="5"
-BGCOLOR="#E0E0F0"
-WIDTH="70%"
-><TR
-><TD
-><PRE
-CLASS="PROGRAMLISTING"
->const usbs_enumeration_data usb_enum_data = {
- …
-};
-
-int
-main(int argc, char** argv)
-{
- usbs_sa11x0_ep0.enumeration_data = &usb_enum_data;
- …
- usbs_start(&usbs_sa11x0_ep0);
- …
-}</PRE
-></TD
-></TR
-></TABLE
-><P
->The exact behaviour of <TT
-CLASS="FUNCTION"
->usbs_start</TT
-> depends on the
-USB hardware and the device driver. A typical implementation would
-change the USB data pins from tristated to active. If the peripheral
-is already plugged into a host then the latter should detect this
-change and start interacting with the peripheral, including requesting
-the enumeration data. Some of this may happen before
-<TT
-CLASS="FUNCTION"
->usbs_start</TT
-> returns, but given that multiple
-interactions between USB host and peripheral are required it is likely
-that the function will return before the peripheral is fully
-configured. Control endpoints provide a <A
-HREF="usbs-control.html#AEN16552"
->mechanism</A
-> for informing
-higher-level code of USB state changes.
-<TT
-CLASS="FUNCTION"
->usbs_start</TT
-> will return even if the peripheral is
-not currently connected to a host: it will not block until the
-connection is established.</P
-><P
-><TT
-CLASS="FUNCTION"
->usbs_start</TT
-> should only be called once for a given
-USB device. There are no defined error conditions. Note that the
-function affects the entire USB device and not just the control
-endpoint: there is no need to start any data endpoints as well.</P
-></DIV
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-CLASS="NAVFOOTER"
-><HR
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-WIDTH="33%"
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-></TD
-></TR
-><TR
-><TD
-WIDTH="33%"
-ALIGN="left"
-VALIGN="top"
->USB Enumeration Data</TD
-><TD
-WIDTH="34%"
-ALIGN="center"
-VALIGN="top"
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-HREF="io-usb-slave.html"
-ACCESSKEY="U"
->Up</A
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