1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 2<html> 3 4<head> 5<META http-equiv="Content-Type" content="text/html; charset=windows-1252"> 6<META name="GENERATOR" content="IBM WebSphere Studio Homepage Builder Version 7.0.0.0 for Windows"> 7<META http-equiv="Content-Style-Type" content="text/css"> 8<title>FS_SetDefaultDMA</title> 9<LINK rel="stylesheet" href="../../css/nitro.css" type="text/css"> 10</head> 11 12<body> 13 14<h1 align="left">FS_SetDefaultDMA <img src="../../image/NTR.gif"align="middle"><img src="../../image/TWL.gif" align="middle"></h1> 15<h2>Syntax</h2> 16 17<dl> 18 <dd> 19<CODE>#include <nitro/fs.h></CODE><BR> <BR> <CODE>u32 FS_SetDefaultDMA( u32 dma_no );</CODE><br> <br> 20 </dd> 21</dl> 22<h2>Arguments</h2> 23<p> 24<TABLE border="1" width="100%"> 25 <TBODY> 26 <TR> 27<TD width="13%"><EM><STRONG>dma_no</STRONG></EM></TD> 28<TD width="87%">The DMA channel used by the ROM archive inside the file system.<BR>Settings can be used as an argument to the <code><a href="../../card/rom/CARD_ReadRomAsync.html">CARD_ReadRomAsync</a></code> function, which is called by the FS library.<BR><FONT color="#800000">When a valid DMA channel is specified, this DMA channel cannot be used until the setting is changed with the <code>FS_SetDefaultDMA</code> function.</FONT><font color="#800000">The card access transfer source is an I/O register, so DMA channel 0 cannot be specified.</font> 29 </TD> 30 </TR> 31 </TBODY> 32</TABLE> 33</p> 34 35<h2>Return Values</h2> 36<p>It returns the DMA channel that was previously set.</p> 37 38<H2>Description</H2> 39<P>Specifies the DMA channel used for Data Access by the <A href="../archive_rom_spec.html">ROM Archive</A> within the file system.<BR>If you specify <code><a href="../fs_dma_not_use_const.html">FS_DMA_NOT_USE</a></code> instead of DMA, it uses the CPU to transfer.<BR> For more information on internal operations when allocating a DMA channel to the <A href="../archive_rom_spec.html"><code>ROM archive</code></A>, refer to the description for the <a href="../../card/rom/CARD_ReadRomAsync.html"><code>CARD_ReadRomAsync</code></a> function. 40</P> 41<H2>Note</H2> 42<P> 43<FONT color="#800000">When a valid DMA channel is specified, this DMA channel cannot be used until the setting is changed with the <code>FS_SetDefaultDMA</code> function. <BR>Also, if the <A href="../archive_rom_spec.html">ROM Archive</A> is being accessed when the configuration is changed, the change is not effective until that file's operation is complete.<br> The FS library uses this DMA channel to access the ROM file system on the card. Refer to the description on the <code><a href="../../card/rom/CARD_ReadRom.html">CARD_ReadRom</a></code> function and <code><a href="../../card/rom/CARD_ReadRomAsync.html">CARD_ReadRomAsync</a></code> functions.</FONT></P> 44<h2>See Also</h2> 45<p><CODE><A href="../fs_dma_not_use_const.html">FS_DMA_NOT_USE</A><BR> <A href="../../card/rom/CARD_ReadRom.html">CARD_ReadRom</A><BR> <A href="../../card/rom/CARD_ReadRomAsync.html">CARD_ReadRomAsync</A></CODE></P> 46<H2>Revision History</H2> 47<P> 482008/01/24 Made slight revisions to the description of DMA channels.<br /> 2005/09/17 Added a note about applying changes to DMA channel settings.<br> 2005/08/28 Added a link to <code>CARD_ReadRomAsync()</code> under Description.<br> 2005/04/28 Added the fact that DMA Channel 0 cannot be specified.<br> 2004/07/23 Added a note about the ROM archives and DMA channels.<BR> 2004/05/14 Added a description of FS_DMA_NOT_USE.<BR> 2004/04/08 Initial version.<BR> 49</P> 50<hr><p>CONFIDENTIAL</p></body> 51</html> 52
