📄 mmc_8c-source.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1"><title>Procyon AVRlib: mmc.c Source File</title><link href="dox.css" rel="stylesheet" type="text/css"></head><body><!-- Generated by Doxygen 1.3.6 --><div class="qindex"><a class="qindex" href="main.html">Main Page</a> | <a class="qindex" href="modules.html">Modules</a> | <a class="qindex" href="annotated.html">Data Structures</a> | <a class="qindex" href="files.html">File List</a> | <a class="qindex" href="functions.html">Data Fields</a> | <a class="qindex" href="globals.html">Globals</a></div><h1>mmc.c</h1><a href="mmc_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre>00001 <span class="comment">/*! \file mmc.c \brief MultiMedia and SD Flash Card Interface. */</span>00002 <span class="comment">//*****************************************************************************</span>00003 <span class="comment">//</span>00004 <span class="comment">// File Name : 'mmc.c'</span>00005 <span class="comment">// Title : MultiMedia and SD Flash Card Interface</span>00006 <span class="comment">// Author : Pascal Stang - Copyright (C) 2004</span>00007 <span class="comment">// Created : 2004.09.22</span>00008 <span class="comment">// Revised : 2004.09.22</span>00009 <span class="comment">// Version : 0.1</span>00010 <span class="comment">// Target MCU : Atmel AVR Series</span>00011 <span class="comment">// Editor Tabs : 4</span>00012 <span class="comment">//</span>00013 <span class="comment">// NOTE: This code is currently below version 1.0, and therefore is considered</span>00014 <span class="comment">// to be lacking in some functionality or documentation, or may not be fully</span>00015 <span class="comment">// tested. Nonetheless, you can expect most functions to work.</span>00016 <span class="comment">//</span>00017 <span class="comment">// This code is distributed under the GNU Public License</span>00018 <span class="comment">// which can be found at http://www.gnu.org/licenses/gpl.txt</span>00019 <span class="comment">//</span>00020 <span class="comment">//*****************************************************************************</span>00021 00022 <span class="comment">//----- Include Files ---------------------------------------------------------</span>00023 <span class="preprocessor">#include <avr/io.h></span> <span class="comment">// include I/O definitions (port names, pin names, etc)</span>00024 <span class="preprocessor">#include <avr/signal.h></span> <span class="comment">// include "signal" names (interrupt names)</span>00025 <span class="preprocessor">#include <avr/interrupt.h></span> <span class="comment">// include interrupt support</span>00026 00027 <span class="preprocessor">#include "<a class="code" href="global_8h.html">global.h</a>"</span> <span class="comment">// include our global settings</span>00028 <span class="preprocessor">#include "<a class="code" href="spi_8h.html">spi.h</a>"</span> <span class="comment">// include spi bus support</span>00029 00030 <span class="preprocessor">#include "<a class="code" href="rprintf_8h.html">rprintf.h</a>"</span>00031 00032 <span class="preprocessor">#include "<a class="code" href="mmc_8h.html">mmc.h</a>"</span>00033 00034 <span class="comment">// include project-specific hardware configuration</span>00035 <span class="preprocessor">#include "<a class="code" href="mmcconf_8h.html">mmcconf.h</a>"</span>00036 00037 <span class="comment">// Global variables</span>00038 00039 <span class="comment">// Functions</span>00040 <a name="l00041"></a><a class="code" href="mmc_8h.html#a42">00041</a> <span class="keywordtype">void</span> <a class="code" href="mmc_8c.html#a0">mmcInit</a>(<span class="keywordtype">void</span>)00042 {00043 <span class="comment">// initialize SPI interface</span>00044 spiInit();00045 <span class="comment">// release chip select</span>00046 sbi(MMC_CS_DDR, MMC_CS_PIN);00047 sbi(MMC_CS_PORT,MMC_CS_PIN);00048 }00049 <a name="l00050"></a><a class="code" href="mmc_8h.html#a43">00050</a> u08 <a class="code" href="mmc_8c.html#a1">mmcReset</a>(<span class="keywordtype">void</span>)00051 {00052 u08 retry;00053 u08 r1=0;00054 00055 retry = 0;00056 <span class="keywordflow">do</span>00057 {00058 <span class="comment">// send dummy bytes with CS high before accessing</span>00059 spiTransferByte(0xFF);00060 spiTransferByte(0xFF);00061 spiTransferByte(0xFF);00062 spiTransferByte(0xFF);00063 <span class="comment">// resetting card, go to SPI mode</span>00064 r1 = <a class="code" href="mmc_8h.html#a44">mmcSendCommand</a>(MMC_GO_IDLE_STATE, 0);00065 rprintf(<span class="stringliteral">"MMC_GO_IDLE_STATE: R1=0x%x\r\n"</span>, r1);00066 <span class="comment">// do retry counter</span>00067 retry++;00068 <span class="keywordflow">if</span>(retry>10) <span class="keywordflow">return</span> -1;00069 } <span class="keywordflow">while</span>(r1 != 0x01);00070 00071 <span class="comment">// TODO: check card parameters for voltage compliance</span>00072 <span class="comment">// before issuing initialize command</span>00073 00074 retry = 0;00075 <span class="keywordflow">do</span>00076 {00077 <span class="comment">// initializing card for operation</span>00078 r1 = <a class="code" href="mmc_8h.html#a44">mmcSendCommand</a>(MMC_SEND_OP_COND, 0);00079 rprintf(<span class="stringliteral">"MMC_SEND_OP_COND: R1=0x%x\r\n"</span>, r1);00080 <span class="comment">// do retry counter</span>00081 retry++;00082 <span class="keywordflow">if</span>(retry>100) <span class="keywordflow">return</span> -1;00083 } <span class="keywordflow">while</span>(r1);00084 00085 <span class="comment">// turn off CRC checking to simplify communication</span>00086 r1 = <a class="code" href="mmc_8h.html#a44">mmcSendCommand</a>(MMC_CRC_ON_OFF, 0);00087 rprintf(<span class="stringliteral">"MMC_CRC_ON_OFF: R1=0x%x\r\n"</span>, r1);00088 00089 <span class="comment">// set block length to 512 bytes</span>00090 r1 = <a class="code" href="mmc_8h.html#a44">mmcSendCommand</a>(MMC_SET_BLOCKLEN, 512);00091 rprintf(<span class="stringliteral">"MMC_SET_BLOCKLEN: R1=0x%x\r\n"</span>, r1);00092 00093 <span class="comment">// return success</span>00094 <span class="keywordflow">return</span> 0;00095 }00096 <a name="l00097"></a><a class="code" href="mmc_8h.html#a44">00097</a> u08 <a class="code" href="mmc_8h.html#a44">mmcSendCommand</a>(u08 cmd, u32 arg)00098 {00099 u08 r1;00100 00101 <span class="comment">// assert chip select</span>00102 cbi(MMC_CS_PORT,MMC_CS_PIN);00103 <span class="comment">// issue the command</span>00104 r1 = <a class="code" href="mmc_8h.html#a47">mmcCommand</a>(cmd, arg);00105 <span class="comment">// release chip select</span>00106 sbi(MMC_CS_PORT,MMC_CS_PIN);00107 00108 <span class="keywordflow">return</span> r1;00109 }00110 <a name="l00111"></a><a class="code" href="mmc_8h.html#a45">00111</a> u08 <a class="code" href="mmc_8h.html#a45">mmcRead</a>(u32 sector, u08* buffer)00112 {00113 u08 r1;00114 u16 i;00115 00116 <span class="comment">// assert chip select</span>00117 cbi(MMC_CS_PORT,MMC_CS_PIN);00118 <span class="comment">// issue command</span>00119 r1 = <a class="code" href="mmc_8h.html#a47">mmcCommand</a>(MMC_READ_SINGLE_BLOCK, sector<<9);00120 rprintf(<span class="stringliteral">"MMC Read Block R1=0x%x\r\n"</span>, r1);00121 <span class="comment">// check for valid response</span>00122 <span class="keywordflow">if</span>(r1 != 0x00)00123 <span class="keywordflow">return</span> r1;00124 <span class="comment">// wait for block start</span>00125 <span class="keywordflow">while</span>(spiTransferByte(0xFF) != MMC_STARTBLOCK_READ);00126 <span class="comment">// read in data</span>00127 <span class="keywordflow">for</span>(i=0; i<0x200; i++)00128 {00129 *buffer++ = spiTransferByte(0xFF);00130 }00131 <span class="comment">// read 16-bit CRC</span>00132 spiTransferByte(0xFF);00133 spiTransferByte(0xFF);00134 <span class="comment">// release chip select</span>00135 sbi(MMC_CS_PORT,MMC_CS_PIN);00136 <span class="comment">// return success</span>00137 <span class="keywordflow">return</span> 0;00138 }00139 <a name="l00140"></a><a class="code" href="mmc_8h.html#a46">00140</a> u08 <a class="code" href="mmc_8h.html#a46">mmcWrite</a>(u32 sector, u08* buffer)00141 {00142 u08 r1;00143 u16 i;00144 00145 <span class="comment">// assert chip select</span>00146 cbi(MMC_CS_PORT,MMC_CS_PIN);00147 <span class="comment">// issue command</span>00148 r1 = <a class="code" href="mmc_8h.html#a47">mmcCommand</a>(MMC_WRITE_BLOCK, sector<<9);00149 rprintf(<span class="stringliteral">"MMC Write Block R1=0x%x\r\n"</span>, r1);00150 <span class="comment">// check for valid response</span>00151 <span class="keywordflow">if</span>(r1 != 0x00)00152 <span class="keywordflow">return</span> r1;00153 <span class="comment">// send dummy</span>00154 spiTransferByte(0xFF);00155 <span class="comment">// send data start token</span>00156 spiTransferByte(MMC_STARTBLOCK_WRITE);00157 <span class="comment">// write data</span>00158 <span class="keywordflow">for</span>(i=0; i<0x200; i++)00159 {00160 spiTransferByte(*buffer++);00161 }00162 <span class="comment">// write 16-bit CRC (dummy values)</span>00163 spiTransferByte(0xFF);00164 spiTransferByte(0xFF);00165 <span class="comment">// read data response token</span>00166 r1 = spiTransferByte(0xFF);00167 <span class="keywordflow">if</span>( (r1&MMC_DR_MASK) != MMC_DR_ACCEPT)00168 <span class="keywordflow">return</span> r1;00169 rprintf(<span class="stringliteral">"Data Response Token=0x%x\r\n"</span>, r1);00170 <span class="comment">// wait until card not busy</span>00171 <span class="keywordflow">while</span>(!spiTransferByte(0xFF));00172 <span class="comment">// release chip select</span>00173 sbi(MMC_CS_PORT,MMC_CS_PIN);00174 <span class="comment">// return success</span>00175 <span class="keywordflow">return</span> 0;00176 }00177 <a name="l00178"></a><a class="code" href="mmc_8h.html#a47">00178</a> u08 <a class="code" href="mmc_8h.html#a47">mmcCommand</a>(u08 cmd, u32 arg)00179 {00180 u08 r1;00181 u08 retry=0;00182 <span class="comment">// send command</span>00183 spiTransferByte(cmd | 0x40);00184 spiTransferByte(arg>>24);00185 spiTransferByte(arg>>16);00186 spiTransferByte(arg>>8);00187 spiTransferByte(arg);00188 spiTransferByte(0x95); <span class="comment">// crc valid only for MMC_GO_IDLE_STATE</span>00189 <span class="comment">// end command</span>00190 <span class="comment">// wait for response</span>00191 <span class="comment">// if more than 8 retries, card has timed-out</span>00192 <span class="comment">// return the received 0xFF</span>00193 <span class="keywordflow">while</span>((r1 = spiTransferByte(0xFF)) == 0xFF)00194 <span class="keywordflow">if</span>(retry++ > 8) <span class="keywordflow">break</span>;00195 <span class="comment">// return response</span>00196 <span class="keywordflow">return</span> r1;00197 }</pre></div><hr size="1"><address style="align: right;"><small>Generated on Fri Oct 15 03:50:22 2004 for Procyon AVRlib by<a href="http://www.doxygen.org/index.html"><img src="doxygen.png" alt="doxygen" align="middle" border=0 > </a>1.3.6 </small></address></body></html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -