ARM学习笔记--NAND Flash控制器 小咪咪 2022-03-26 13:52 168阅读 0赞 摘自:《嵌入式Linux应用开发完全手册》——韦东山 一、NAND Flash介绍和NAND Flash控制器的使用 NAND Flash在嵌入式系统中的作用,相当于PC上的硬盘 常见的Flash有NOR Flash和NAND Flash,NOR Flash上进行读取的效率非常高,但是擦除和写操作的效率很低,容量一般比较小;NAND Flash进行擦除和写操作的效率更高,并且容量更大。一般NOR Flash用于存储程序,NAND Flash用于存储数据。 1)NAND Flash的物理结构 笔者用的开发板上NAND Flash型号是K9F1G08,大小为128M,下图为它的封装和外部引脚 ![201004111728211471.jpg][] \* NandFlash接口信号较少 \*数据宽度只有8Bit,没有地址总线。地址和数据总线复用,串行读取 <table style="border-bottom:medium none; border-left:medium none; width:395.25pt; border-collapse:collapse; border-top:medium none; border-right:medium none"> <tbody> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">信号名称</span><span style="font-size:9pt"></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">信号描述</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">IO[7..0]</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">数据总线</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">CE#</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">片选信号</span><span style="font-size:9pt"><span style="font-family:Calibri">(Chip Select)</span></span><span style="font-family:宋体; font-size:9pt">,低电平有效</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">WE#</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">写有效</span><span style="font-size:9pt"><span style="font-family:Calibri">(Write Enable)</span></span><span style="font-family:宋体; font-size:9pt">,低电平表示当前总线操作是写操作</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">RE#</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">读有效</span><span style="font-size:9pt"><span style="font-family:Calibri">(Read Enable)</span></span><span style="font-family:宋体; font-size:9pt">,低电平表示当前总线操作是读操作</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">CLE</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">命令锁存</span><span style="font-size:9pt"><span style="font-family:Calibri">(Command Latch Enable)</span></span><span style="font-family:宋体; font-size:9pt">信号,写操作时给出此信号表示写命令</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">ALE</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">地址</span><span style="font-size:9pt"><span style="font-family:Calibri">/</span></span><span style="font-family:宋体; font-size:9pt">数据锁存</span><span style="font-size:9pt"><span style="font-family:Calibri">(Address Latch Enable)</span></span><span style="font-family:宋体; font-size:9pt">信号,写操作时给出此信号表示写地址或数据</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">WP#</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">写保护</span><span style="font-size:9pt"><span style="font-family:Calibri">(Write Protect)</span></span><span style="font-family:宋体; font-size:9pt">信号</span><span style="font-size:9pt"></span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:55.05pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:center; margin:0cm 0cm 0pt"><span><span style="font-family:Calibri">R/B</span></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:12cm; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="margin:0cm 0cm 0pt"><span style="font-family:宋体; font-size:9pt">忙</span><span style="font-size:9pt"><span style="font-family:Calibri">(Read/Busy)</span></span><span style="font-family:宋体; font-size:9pt">信号</span><span style="font-size:9pt"></span></p> </td> </tr> </tbody> </table> 2)K9F1G08功能结构图如下 ![201004111730385042.jpg][] K9F1G08内部结构有下面一些功能部件 ①X-Buffers Latches & Decoders:用于行地址 ②X-Buffers Latches & Decoders:用于列地址 ③Command Register:用于命令字 ④Control Logic & High Voltage Generator:控制逻辑及产生Flash所需高压 ⑤Nand Flash Array:存储部件 ⑥Data Register & S/A:数据寄存器,读、写页时,数据存放此寄存器 ⑦Y-Gating ⑧I/O Buffers & Latches ⑨Global Buffers ⑩Output Driver 3)NAND Flash 存储单元组织结构图如下: ![201004111745084806.jpg][] K9F1G08容量为1056Mbit,分为65536行(页)、2112列,每一页大小为2kb,外加64字节的额外空间,这64字节的额外空间的列地址为2048-2111 命令、地址、数据都通过IO0-IO7输入/输出,写入命令、地址或数据时,需要将WE、CE信号同时拉低,数据在WE信号的上升沿被NAND FLash锁存;命令锁存信号CLE、地址锁存信号ALE用来分辨、锁存命令或地址。 K9F1G08有128MB的存储空间,需要27位地址,以字节为单位访问Flash时,需要4个地址序列 NandFlash地址结构 \* NandFlash设备的存储容量是以页(Page)和块(Block)为单位的。 \* Page=528Byte (512Byte用于存放数据,其余16Byte用于存放其他信息,如块好坏的标记、块的逻辑地址、页内数据的ECC校验和等)。 \* Block=32Page \*容量为64MB的NandFlash存储结构为:512Byte×32Page×4096Block \* NandFlash以页为单位进行读和编程(写)操作,一页为512Byte;以块为单位进行擦除操作,一块为512Byte\*32page=16KB \*对于64MB的NAND设备,需要26根地址线,由于NAND设备数据总线宽度是8位的,因此必须经过4个时钟周期才能把全部地址信息接收下来 <table style="border-bottom:medium none; border-left:medium none; border-collapse:collapse; border-top:medium none; border-right:medium none"> <tbody> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:85.3pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"> </span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O7</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O6</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O5</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O4</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O3</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O2</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O1</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:black 1pt solid; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">I/O0</span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:85.3pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:宋体; color:black; font-size:12pt">第一个周期</span><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A7</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A6</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A5</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A4</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A3</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A2</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A1</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A0</span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:85.3pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:宋体; color:black; font-size:12pt">第二个周期</span><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A15</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A14</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A13</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A12</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A11</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A10</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A9</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A8</span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:85.3pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:宋体; color:black; font-size:12pt">第三个周期</span><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A23</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A22</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A21</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A20</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A19</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A18</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A17</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A16</span></p> </td> </tr> <tr> <td style="border-bottom:black 1pt solid; border-left:black 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:85.3pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:宋体; color:black; font-size:12pt">第四个周期</span><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"></span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"> </span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"> </span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"> </span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"> </span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"> </span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt"> </span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A25</span></p> </td> <td style="border-bottom:black 1pt solid; border-left:#d4d0c8; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:42.6pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:black 1pt solid; padding-top:0cm"> <p style="text-align:left; margin:12pt 0cm 6pt"><span style="font-family:'Verdana','sans-serif'; color:black; font-size:12pt">A24</span></p> </td> </tr> </tbody> </table> \*可以这么说,第一个时钟周期给出的是目标地址在一个page内的偏移量,而后三个时钟周期给出的是页地址。 \*由于一个页内有512Byte,需要9bit的地址寻址,而第一个时钟周期只给出了低8bit,最高位A8由不同的读命令(Read Mode2)来区分的。 4). **NandFlash的命令** ![\[ARM笔记\]存储器扩展连接理解(S3C2410为例)—NandFlash - Fantity Wei - Footprint][ARM_S3C2410_NandFlash - Fantity Wei - Footprint] NAND Flash访问方法 NAND Flash硬件连接如下图: ![201004111631128652.jpg][] NAND Flash和S3C2440的连线包括,8个IO引脚,5个使能信号(nWE、ALE、CLE、nCE、nRE)、1个状态引脚(R/B)、1个写保护引脚(nWP)。地址、数据和命令都是在这些使能信号的配合下,通过8个IO引脚传输。写地址、数据、命令时,nCE、nWE信号必须为低电平,它们在 nWE信号的上升沿被锁存。命令锁存使能信号CLE和地址锁存使能信号ALE用来区别IO引脚上传输的是命令还是地址。 命令字及操作方法 操作NAND Flash时,先传输命令,然后传输地址,最后读写数据,这个期间要检查Flash的状态。K9F1G08容量为128MB,需要一个27位的地址,发出命令后,后面要紧跟着4个地址序列。 下图为K9F1G08的命令字 ![201004112037412468.jpg][] 下图为K9F1G08的地址序列 ![201004111816106632.jpg][] K9F1G08有2112列,所以必须使用A0-A11共12位来寻址,有65535行,所以必须使用A12-A27共16位来寻址。 3)S3C2440 NAND Flash控制器介绍 NAND Flash的读写操作次序如下: ①设置NFCONF配置NAND Flash ②向NFCMD寄存器写入命令 ③向NFADDR寄存器写入地址 ④读写数据:通过寄存器NFSTAT检测NAND Flash的状态,在启动某个操作后,应该检测R/nB信号以确定该操作是否完成、是否成功。 下面介绍这些寄存器: ①NFCONF:配置寄存器 用来设置NAND Flash的时序参数,设置数据位宽,设置是否支持其他大小的页等。 ②NFCONT:控制寄存器 用来使能NAND Flash控制器、使能控制引脚信号nFCE、初始化ECC,锁定NAND Flash等功能 ③NFCMD:命令寄存器 用来发送Flash操作命令 ④NFADDR:地址寄存器 用来向Flash发送地址信号 ⑤NFDATA:数据寄存器 读写此寄存器启动对NAND Flash的读写数据操作 ⑥NFSTAT:状态寄存器 0:busy,1:ready 二、NAND Flash控制器操作实例:读Flash 1)读NAND Flash的步骤 ①设置NFCONF 在HCLK=100Mhz的情况下,TACLS=0,TWRPH0=3,TWRPH1=0,则 NFCONF = 0x300 使能NAND Flash控制器、禁止控制引脚信号nFCE,初始化ECC NFCONT = (1<<4) | (1<<1) | (1<<0) ②操作NAND Flash前,复位 NFCONT &= ~(1<<1) 发出片选信号 NFCMD = 0xff reset命令 然后循环查询NFSTAT位0,直到等于1,处于就绪态 最后禁止片选信号,在实际使用时再使能 NFCONT |= 0x2 禁止NAND Flash ③发出读命令 NFCONT &= ~(1<<1) 发出片选信号 NFCMD = 0 读命令 ④发出地址信号 ⑤循环查询NFSTAT,直到等于1 ⑥连续读NFDATA寄存器,得到一页数据 ⑦最后禁止NAND Flash片选信号 NFCONT |= (1<<1) 2)代码详解 本实例的目的是把一部分代码存放在NAND Flash地址4096之后,当程序启动后通过NAND Flash控制器读出代码,执行。 连接脚本 nand.lds SECTIONS \{ firtst 0x00000000 : \{ head.o init.o nand.o\} second 0x30000000 : AT(4096) \{ main.o \} \} head.o init.o nand.o三个文件运行地址为0,生成的镜像文件偏移地址也为0 main.0的运行地址为0x30000000,生成的镜像文件偏移地址为4096 @\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* @ File:head.s @ 功能:设置SDRAM,将程序复制到SDRAM,然后跳到SDRAM继续执行 @\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* .text .global \_start \_start: @函数disable\_watch\_dog, memsetup, init\_nand, nand\_read\_ll在init.c中定义 ldr sp, =4096 @设置堆栈 bl disable\_watch\_dog @关WATCH DOG bl memsetup @初始化SDRAM bl nand\_init @初始化NAND Flash @将NAND Flash中地址4096开始的1024字节代码(main.c编译得到)复制到SDRAM中 @nand\_read\_ll函数需要3个参数: ldr r0, =0x30000000 @1. 目标地址=0x30000000,这是SDRAM的起始地址 mov r1, \#4096 @2. 源地址 = 4096,连接的时候,main.c中的代码都存在NAND Flash地址4096开始处 mov r2, \#2048 @3. 复制长度= 2048(bytes),对于本实验的main.c,这是足够了 bl nand\_read @调用C函数nand\_read ldr sp, =0x34000000 @设置栈 ldr lr, =halt\_loop @设置返回地址 ldr pc, =main @b指令和bl指令只能前后跳转32M的范围,所以这里使用向pc赋值的方法进行跳转 halt\_loop: b halt\_loop init.c 用于初始化操作 /\* WOTCH DOG register \*/ \#define WTCON(\*(volatile unsigned long \*)0x53000000) /\* SDRAM regisers \*/ \#define MEM\_CTL\_BASE0x48000000 void disable\_watch\_dog(); void memsetup(); /\*上电后,WATCH DOG默认是开着的,要把它关掉 \*/ void disable\_watch\_dog() \{ WTCON= 0; \} /\* 设置控制SDRAM的13个寄存器 \*/ void memsetup() \{ int i = 0; unsigned long \*p = (unsigned long \*)MEM\_CTL\_BASE; /\* SDRAM 13个寄存器的值 \*/ unsigned long const mem\_cfg\_val\[\]=\{ 0x22011110, //BWSCON 0x00000700, //BANKCON0 0x00000700, //BANKCON1 0x00000700, //BANKCON2 0x00000700, //BANKCON3 0x00000700, //BANKCON4 0x00000700, //BANKCON5 0x00018005, //BANKCON6 0x00018005, //BANKCON7 0x008C07A3, //REFRESH 0x000000B1, //BANKSIZE 0x00000030, //MRSRB6 0x00000030, //MRSRB7 \}; for(; i < 13; i++) p\[i\] = mem\_cfg\_val\[i\]; \} nand.c 用于操作nand flash \#define BUSY 1 \#define NAND\_SECTOR\_SIZE\_LP 2048 //K9F1G08使用2048+64列 \#define NAND\_BLOCK\_MASK\_LP (NAND\_SECTOR\_SIZE\_LP - 1) typedef unsigned int S3C24X0\_REG32; typedef struct \{ S3C24X0\_REG32 NFCONF; S3C24X0\_REG32 NFCONT; S3C24X0\_REG32 NFCMD; S3C24X0\_REG32 NFADDR; S3C24X0\_REG32 NFDATA; S3C24X0\_REG32 NFMECCD0; S3C24X0\_REG32 NFMECCD1; S3C24X0\_REG32 NFSECCD; S3C24X0\_REG32 NFSTAT; S3C24X0\_REG32 NFESTAT0; S3C24X0\_REG32 NFESTAT1; S3C24X0\_REG32 NFMECC0; S3C24X0\_REG32 NFMECC1; S3C24X0\_REG32 NFSECC; S3C24X0\_REG32 NFSBLK; S3C24X0\_REG32 NFEBLK; \} S3C2440\_NAND; //此结构体存储操作NAND Flash相关寄存器 typedef struct \{ void (\*nand\_reset)(void); void (\*wait\_idle)(void); void (\*nand\_select\_chip)(void); void (\*nand\_deselect\_chip)(void); void (\*write\_cmd)(int cmd); void (\*write\_addr)(unsigned int addr); unsigned char (\*read\_data)(void); \}t\_nand\_chip; //存储nand相关操作的函数地址 static S3C2440\_NAND \* s3c2440nand = (S3C2440\_NAND \*)0x4e000000; //s2c2440nand控制器地址 static t\_nand\_chip nand\_chip; /\* 供外部调用的函数 \*/ void nand\_init(void); void nand\_read(unsigned char \*buf, unsigned long start\_addr, int size); /\* NAND Flash操作的总入口, 它们将调用S3C2440的相应函数 \*/ static void nand\_reset(void); static void wait\_idle(void); static void nand\_select\_chip(void); static void nand\_deselect\_chip(void); static void write\_cmd(int cmd); static void write\_addr(unsigned int addr); static unsigned char read\_data(void); /\* S3C2440的NAND Flash处理函数 \*/ static void s3c2440\_nand\_reset(void); static void s3c2440\_wait\_idle(void); static void s3c2440\_nand\_select\_chip(void); static void s3c2440\_nand\_deselect\_chip(void); static void s3c2440\_write\_cmd(int cmd); static void s3c2440\_write\_addr(unsigned int addr); static unsigned char s3c2440\_read\_data(void); /\* S3C2440的NAND Flash操作函数 \*/ /\* 复位 \*/ static void s3c2440\_nand\_reset(void) \{ s3c2440\_nand\_select\_chip(); s3c2440\_write\_cmd(0xff); // 复位命令 s3c2440\_wait\_idle(); s3c2440\_nand\_deselect\_chip(); \} /\* 等待NAND Flash就绪 \*/ static void s3c2440\_wait\_idle(void) \{ int i; volatile unsigned char \*p = (volatile unsigned char \*)&s3c2440nand->NFSTAT; while(!(\*p & BUSY)) //\*p=1表示就绪,跳出循环 for(i=0; i<10; i++); \} /\* 发出片选信号 \*/ static void s3c2440\_nand\_select\_chip(void) \{ int i; s3c2440nand->NFCONT &= ~(1<<1); for(i=0; i<10; i++); \} /\* 取消片选信号 \*/ static void s3c2440\_nand\_deselect\_chip(void) \{ s3c2440nand->NFCONT |= (1<<1); \} /\* 发出命令 \*/ static void s3c2440\_write\_cmd(int cmd) \{ volatile unsigned char \*p = (volatile unsigned char \*)&s3c2440nand->NFCMD; \*p = cmd; \} /\* 发出地址 \*/ static void s3c2440\_write\_addr\_lp(unsigned int addr) \{ int i; volatile unsigned char \*p = (volatile unsigned char \*)&s3c2440nand->NFADDR; int col, page; col = addr & NAND\_BLOCK\_MASK\_LP; //取得列地址 page = addr / NAND\_SECTOR\_SIZE\_LP; //取得行地址 \*p = col & 0xff; /\* 列地址 A0~A7 \*/ for(i=0; i<10; i++); \*p = (col >> 8) & 0x0f; /\* 列地址 A8~A11 \*/ for(i=0; i<10; i++); \*p = page & 0xff; /\* 行地址 A12~A19 \*/ for(i=0; i<10; i++); \*p = (page >> 8) & 0xff; /\* 行地址 A20~A27 \*/ for(i=0; i<10; i++); \*p = (page >> 16) & 0x03; /\* 行地址 A28~A29 \*/ for(i=0; i<10; i++); \} /\* 读取数据 \*/ static unsigned char s3c2440\_read\_data(void) \{ volatile unsigned char \*p = (volatile unsigned char \*)&s3c2440nand->NFDATA; return \*p; \} /\* 在第一次使用NAND Flash前,复位一下NAND Flash \*/ static void nand\_reset(void) \{ nand\_chip.nand\_reset(); \} static void wait\_idle(void) \{ nand\_chip.wait\_idle(); \} static void nand\_select\_chip(void) \{ int i; nand\_chip.nand\_select\_chip(); for(i=0; i<10; i++); \} static void nand\_deselect\_chip(void) \{ nand\_chip.nand\_deselect\_chip(); \} static void write\_cmd(int cmd) \{ nand\_chip.write\_cmd(cmd); \} static void write\_addr(unsigned int addr) \{ nand\_chip.write\_addr(addr); \} static unsigned char read\_data(void) \{ return nand\_chip.read\_data(); \} /\* 初始化NAND Flash \*/ void nand\_init(void) \{ \#define TACLS 0 \#define TWRPH0 3 \#define TWRPH1 0 nand\_chip.nand\_reset = s3c2440\_nand\_reset; nand\_chip.wait\_idle = s3c2440\_wait\_idle; nand\_chip.nand\_select\_chip = s3c2440\_nand\_select\_chip; nand\_chip.nand\_deselect\_chip = s3c2440\_nand\_deselect\_chip; nand\_chip.write\_cmd = s3c2440\_write\_cmd; nand\_chip.write\_addr = s3c2440\_write\_addr\_lp; nand\_chip.read\_data = s3c2440\_read\_data; /\* 设置时序 \*/ s3c2440nand->NFCONF = (TACLS<<12)|(TWRPH0<<8)|(TWRPH1<<4); /\* 使能NAND Flash控制器, 初始化ECC, 禁止片选 \*/ s3c2440nand->NFCONT = (1<<4)|(1<<1)|(1<<0); /\* 复位NAND Flash \*/ nand\_reset(); \} /\* 读函数 用于把nand flash中代码复制到sdram中\*/ void nand\_read(unsigned char \*buf, unsigned long start\_addr, int size) \{ int i, j; if ((start\_addr & NAND\_BLOCK\_MASK\_LP) || (size & NAND\_BLOCK\_MASK\_LP)) \{ return ; /\* 地址或长度不对齐 \*/ \} /\* 选中芯片 \*/ nand\_select\_chip(); for(i=start\_addr; i < (start\_addr + size);) \{ /\* 发出READ命令 \*/ write\_cmd(0); /\* 写地址 \*/ write\_addr(i); write\_cmd(0x30); wait\_idle(); for(j=0; j < NAND\_SECTOR\_SIZE\_LP; j++, i++) \{ \*buf = read\_data(); buf++; \} \} /\* 取消片选信号 \*/ nand\_deselect\_chip(); return ; \} main.c 很简单,点灯 \#defineGPBCON(\*(volatile unsigned long \*)0x56000010) \#defineGPBDAT(\*(volatile unsigned long \*)0x56000014) \#defineGPB5\_out(1<<(5\*2)) \#defineGPB6\_out(1<<(6\*2)) \#defineGPB7\_out(1<<(7\*2)) \#defineGPB8\_out(1<<(8\*2)) void wait(unsigned long dly) \{ for(; dly > 0; dly--); \} int main(void) \{ unsigned long i = 0; GPBCON = GPB5\_out|GPB6\_out|GPB7\_out|GPB8\_out; // 将LED1-4对应的GPB5/6/7/8四个引脚设为输出 GPBDAT = ~(1<<5) | ~(1<<7) | ~(1<<8); while(1)\{ wait(30000); GPBDAT = (~(i<<5));// 根据i的值,点亮LED1-4 if(++i == 16) i = 0; \} return 0; \} 最后是Makefile objs := head.o init.o nand.o main.o nand.bin : $(objs) arm-linux-ld -Tnand.lds\-o nand\_elf $^ arm-linux-objcopy -O binary -S nand\_elf $@ arm-linux-objdump -D -m arm nand\_elf > nand.dis %.o:%.c arm-linux-gcc -Wall -c -O2 -o $@ $< %.o:%.S arm-linux-gcc -Wall -c -O2 -o $@ $< clean: rm -f nand.dis nand.bin nand\_elf \*.o [201004111728211471.jpg]: http://www.sectop.com/upload/2010/4/201004111728211471.jpg [201004111730385042.jpg]: http://www.sectop.com/upload/2010/4/201004111730385042.jpg [201004111745084806.jpg]: http://www.sectop.com/upload/2010/4/201004111745084806.jpg [ARM_S3C2410_NandFlash - Fantity Wei - Footprint]: http://img389.ph.126.net/opZ9q8zst_pPDoUnUb9W7g==/1048212813271642750.jpg [201004111631128652.jpg]: http://www.sectop.com/upload/2010/4/201004111631128652.jpg [201004112037412468.jpg]: http://www.sectop.com/upload/2010/4/201004112037412468.jpg [201004111816106632.jpg]: http://www.sectop.com/upload/2010/4/201004111816106632.jpg
还没有评论,来说两句吧...