1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> 2<head> 3<META http-equiv="Content-Type" content="text/html; charset=windows-1252"> 4<title>SND_SetupChannelNoise</title> 5<link rel="stylesheet" href="../css/nitro.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.65.1"> 7</head> 8<body> 9<div class="refentry" lang="ja"><a name="IDAFLWT"></a><div class="titlepage"> 10<div></div> 11<div></div> 12</div> 13<h1>SND_SetupChannelNoise <IMG src="../image/NTR.gif" width="24" height="12" border="0" align=middle><IMG src="../image/TWL.gif" width="24" height="12" border="0" align=middle></h1> 14<h2>Syntax</h2> 15<dl> 16<dd><pre class="funcsynopsisinfo"><code>#include <nitro/snd.h></code></pre></dd> 17<dd><pre class="funcprototype"><code class="funcprototype">void SND_SetupChannelNoise( 18 int <var>chNo</var>, 19 int <var>volume</var>, 20 SNDChannelDataShift <var>shift</var>, 21 int <var>timer</var>, 22 int <var>pan</var> );</code><br></pre></dd> 23</dl> 24<div class="refsection" lang="ja"><a name="IDAKNWT"></a> 25 <h2>Arguments</h2> 26 27 <div class="variablelist"> 28<table border="0"> 29<col align="left" valign="top"> 30<tbody> 31<tr> 32<td><em><strong><code>chNo</code></strong></em></td> 33<td>The channel number. Takes a value between 14 and 15.</td> 34</tr> 35<tr> 36<td><em><strong><code>volume</code></strong></em></td> 37<td>The volume. Takes a value between 0 and 127.</td> 38</tr> 39<tr> 40<td><em><strong><code>shift</code></strong></em></td> 41<td>Data shift specification.</td> 42</tr> 43<tr> 44<td><em><strong><code>timer</code></strong></em></td> 45<td>The timer. Takes a value between 0x10 and 0xffff.</td> 46</tr> 47<tr> 48<td><em><strong><code>pan</code></strong></em></td> 49<td>The pan. Takes values in the range of 0 (left) to 64 (center) to 127 (right).</td> 50</tr> 51</tbody> 52</table> 53</div> 54 55 </div> 56<div class="refsection" lang="ja"><a name="IDAVOWT"></a> 57 <h2>Return Values</h2> 58 59 <p>None.</p> 60 </div> 61<div class="refsection" lang="ja"><a name="IDA2OWT"></a> 62 <h2>Description</h2> 63 <p> 64This function sets up a channel for playing white noise. 65</p> 66 <p> 67The function sets the parameters for the channel specified by <em><strong><code>chNo</code></strong></em>. The channel must first be locked by the <tt class="function"><a href="SND_LockChannel.html">SND_LockChannel</a></tt> function. Once the parameters have been set, call the <tt class="function"><a href="SND_StartTimer.html">SND_StartTimer</a></tt> function to begin actual playback. 68</p> 69 70 <p> 71Choose from among these values for the data shift setting <code>shift</code>: 72</p> 73 <div class="table"><a name="IDAWPWT"></a><p class="title"><b><b>Table. SNDChannelDataShift</b></b></p> 74<table summary="SNDChannelDataShift" border="1"> 75<colgroup><col><col></colgroup> 76<thead> 77<tr> 78<th>Label</th> 79<th>Description</th> 80</tr> 81</thead> 82<tbody> 83<tr> 84<td>SND_CHANNEL_DATASHIFT_NONE</td> 85<td>Do not perform a data shift.</td> 86</tr> 87<tr> 88<td>SND_CHANNEL_DATASHIFT_1BIT</td> 89<td>Shift data 1 bit right.</td> 90</tr> 91<tr> 92<td>SND_CHANNEL_DATASHIFT_2BIT</td> 93<td>Shift data 2 bits right.</td> 94</tr> 95<tr> 96<td>SND_CHANNEL_DATASHIFT_4BIT</td> 97<td>Shift data 4 bits right.</td> 98</tr> 99</tbody> 100</table> 101</div> 102 103 <p> 104<em>timer</em> specifies 8 cycles of white noise by clock count. The number of ticks per second is approximately 16.757 MHz with <code>SND_TIMER_CLOCK</code>. For example, the following calculation will play a pitch that has a frequency <em>freq</em> Hz. 105</p> 106<pre class="programlisting">timer = <code>SND_TIMER_CLOCK</code> / ( 8 * <em>freq</em> )</pre> 107 <p> 108 109</p> 110 <div class="note"> 111<h3 class="title">Note</h3> 112<p> 113This function is an ARM7 reserved function. After this function is called, its processing will occur only after the command is issued with the <tt class="function"><a href="SND_FlushCommand.html">SND_FlushCommand</a></tt> function. 114</p> 115<p> 116If program execution must be synchronized with process completion, first use the <tt class="function"><a href="SND_GetCurrentCommandTag.html">SND_GetCurrentCommandTag</a></tt> function to obtain the command tag immediately after calling this function. Then, after the command is issued, use the command tag and call either the <tt class="function"><a href="SND_IsFinishedCommandTag.html">SND_IsFinishedCommandTag</a></tt> or <tt class="function"><a href="SND_WaitForCommandProc.html">SND_WaitForCommandProc</a></tt> function to confirm that processing has finished or to wait for it to complete. 117</p> 118</div> 119 </div> 120<h2>See Also</h2> 121<p><code><a href="SND_LockChannel.html">SND_LockChannel</a>, <a href="SND_StartTimer.html">SND_StartTimer</a>, <a href="SND_FlushCommand.html">SND_FlushCommand</a>, <a href="SND_GetCurrentCommandTag.html">SND_GetCurrentCommandTag</a>, <a href="SND_IsFinishedCommandTag.html">SND_IsFinishedCommandTag</a>, <a href="SND_WaitForCommandProc.html">SND_WaitForCommandProc</a></code></p> 122<h2>Revision History</h2> 123<p> 1242005/02/17 Added a note about ARM7 command processing. <br>2004/08/10 Initial version. 125</p> 126</div> 127<hr><p>CONFIDENTIAL</p></body> 128</html> 129
