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<!-- Copyright (C) 2003 Red Hat, Inc. --> <!-- This material may be distributed only subject to the terms --> <!-- and conditions set forth in the Open Publication License, v1.0 --> <!-- or later (the latest version is presently available at --> <!-- http://www.opencontent.org/openpub/). --> <!-- Distribution of the work or derivative of the work in any --> <!-- standard (paper) book form is prohibited unless prior --> <!-- permission is obtained from the copyright holder. --> <HTML ><HEAD ><TITLE >RedBoot Startup Mode</TITLE ><meta name="MSSmartTagsPreventParsing" content="TRUE"> <META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="eCos Reference Manual" HREF="ecos-ref.html"><LINK REL="UP" TITLE="Getting Started with RedBoot" HREF="getting-started-with-redboot.html"><LINK REL="PREVIOUS" TITLE="RedBoot Editing Commands" HREF="redboot-editing-commands.html"><LINK REL="NEXT" TITLE="RedBoot Resource Usage" HREF="resource-usage.html"></HEAD ><BODY CLASS="SECT1" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >eCos Reference Manual</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="redboot-editing-commands.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" >Chapter 1. Getting Started with RedBoot</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="resource-usage.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="STARTUP-MODE">RedBoot Startup Mode</H1 ><P > </P ><P >RedBoot can normally be configured to run in a number of startup modes (or just "modes" for short), determining its location of residence and execution: <P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT >ROM mode</DT ><DD ><P >In this mode, RedBoot both resides and executes from ROM memory (flash or EPROM). This mode is used when there are limited RAM resources. The flash commands cannot update the region of flash where the RedBoot image resides. In order to update the RedBoot image in flash, it is necessary to run a RAM mode instance of RedBoot.</P ></DD ><DT >ROMRAM mode</DT ><DD ><P >In this mode, RedBoot resides in ROM memory (flash or EPROM), but is copied to RAM memory before it starts executing. The RAM footprint is larger than for ROM mode, but there are two advantages to make up for this: it normally runs faster (relevant only on slower boards) and it is able to update the flash region where the image resides.</P ></DD ><DT >RAM mode</DT ><DD ><P >In this mode, RedBoot both resides and executes from RAM memory. This is used for updating a primary ROM mode image in situ and sometimes as part of the RedBoot installation on the board when there's already an existing (non-RedBoot) boot monitor available.</P ><P > You can only use ROM and ROMRAM mode images for booting a board - a RAM mode image cannot run unless loaded by another ROM monitor. There is no need for this startup mode if a RedBoot ROMRAM mode image is the primary boot monitor. When this startup mode is programmed into flash (as a convenience as it's fast to load from flash) it will generally be named as "RedBoot[RAM]" in the FIS directory. </P ></DD ></DL ></DIV > The chosen mode has influence on flash and RAM resource usage (see <A HREF="resource-usage.html" >the Section called <I >RedBoot Resource Usage</I ></A >) and the procedure of an in situ update of RedBoot in flash (see <A HREF="updating-redboot.html" >Chapter 4</A >).</P ><P >The startup mode is controlled by the option CYG_HAL_STARTUP which resides in the platform HAL. Some platforms provide only some of the RAM, ROM, and ROMRAM modes, others provide additional modes.</P ><P >To see mode of a currently executing RedBoot, issue the <B CLASS="COMMAND" >version</B > command, which prints the RedBoot banner, including the startup mode (here ROM): <TABLE BORDER="5" BGCOLOR="#E0E0F0" WIDTH="70%" ><TR ><TD ><PRE CLASS="SCREEN" >RedBoot><TT CLASS="USERINPUT" ><B >version</B ></TT > RedBoot(tm) bootstrap and debug environment <SPAN CLASS="emphasis" ><I CLASS="EMPHASIS" >[ROM]</I ></SPAN > Non-certified release, version UNKNOWN - built 13:31:57, May 17 2002</PRE ></TD ></TR ></TABLE ></P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="redboot-editing-commands.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ecos-ref.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="resource-usage.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >RedBoot Editing Commands</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="getting-started-with-redboot.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >RedBoot Resource Usage</TD ></TR ></TABLE ></DIV ></BODY ></HTML >
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