您的位置:首页 > 其它

STM32学习笔记——FSMC 驱动大容量NAND FLASH [复制链接]

2013-10-30 15:19 375 查看
本文原创于观海听涛,原作者版权所有,转载请注明出处。 近几天开发项目需要用到STM32驱动NAND FLASH,但由于开发板例程以及固件库是用于小页(512B),我要用到的FLASH为1G bit的大页(2K),多走了两天弯路。以下笔记将说明如何将默认固件库修改为大页模式以驱动大容量NAND,并作驱动。
本文硬件:控制器:STM32F103ZET6,存储器:HY27UF081G2A
首先说一下NOR与NAND存储器的区别,此类区别网上有很多,在此仅大致说明:
1、Nor读取速度比NAND稍快 2、Nand写入速度比Nor快很多 3、NAND擦除速度(4ms)远快于Nor(5s) 4、Nor 带有SRAM接口,有足够的地址引脚来寻址,可以很轻松的挂接到CPU地址和数据总线上,对CPU要求低 5、NAND用八个(或十六个)引脚串行读取数据,数据总线地址总线复用,通常需要CPU支持驱动,且较为复杂 6、Nor主要占据1-16M容量市场,并且可以片内执行,适合代码存储 7、NAND占据8-128M及以上市场,通常用来作数据存储 8、NAND便宜一些 9、NAND寿命比Nor长 10、NAND会产生坏块,需要做坏块处理和ECC 更详细区别请继续百度,以上内容部分摘自神舟三号开发板手册
下面是NAND的存储结构:
由此图可看出NAND存储结构为立体式 正如硬盘的盘片被分为磁道,每个磁道又分为若干扇区,一块nand flash也分为若干block,每个block分为如干page。一般而言,block、page之间的关系随着芯片的不同而不同。 需要注意的是,对于flash的读写都是以一个page开始的,但是在读写之前必须进行flash的擦写,而擦写则是以一个block为单位的。 我们这次使用的HY27UF081G2A其PDF介绍: Memory Cell Array = (2K+64) Bytes x 64 Pages x 1,024 Blocks 由此可见,该NAND每页2K,共64页,1024块。其中:每页中的2K为主容量Data Field,64bit为额外容量Spare Field。Spare Field用于存贮检验码和其他信息用的,并不能存放实际的数据。由此可算出系统总容量为2K*64*1024=134217728个byte,即1Gbit。 NAND闪存颗粒硬件接口: 由此图可见,此颗粒为八位总线,地址数据复用,芯片为SOP48封装。
软件驱动:(此部分写的是伪码,仅用于解释含义,可用代码参见附件) 主程序:

#define BUFFER_SIZE 0x2000 //此部分定义缓冲区大小,即一次写入的数据

#define NAND_HY_MakerID 0xAD //NAND厂商号

#define NAND_HY_DeviceID 0xF1 //NAND器件号

/*配置与SRAM连接的FSMC BANK2 NAND*/

NAND_Init();

/*读取Nand Flash ID并打印*/

NAND_ReadID(&NAND_ID);

复制代码

Tips:NAND器件的ID包含四部分: 1st Manufacturer Code
2nd Device Identifier 3rd Internal chip number, cell Type, Number of Simultaneously Programmed pages. 4th Page size, spare size, Block size, Organization


if((NAND_ID.Maker_ID == NAND_HY_MakerID) && (NAND_ID.Device_ID == NAND_HY_DeviceID)) //判断器件符合

{

/*设置NAND FLASH的写地址*/

WriteReadAddr.Zone = 0x00;

WriteReadAddr.Block = 0x00;

WriteReadAddr.Page = 0x05;

/*擦除待写入数据的块*/

status = NAND_EraseBlock(WriteReadAddr); //写入前必须擦出

/*将写Nand Flash的数据BUFFER填充为从0x25开始的连续递增的一串数据 */

Fill_Buffer(TxBuffer, BUFFER_SIZE , 0x25); //填充数据以测试

/*将数据写入到Nand Flash中。WriteReadAddr:读写的起始地址*/

status = NAND_WriteSmallPage(TxBuffer, WriteReadAddr, PageNumber); //主要写入函数,此部分默认为小页需要修改

/*从Nand Flash中读回刚写入的数据。riteReadAddr:读写的起始地址*/

status = NAND_ReadSmallPage (RxBuffer, WriteReadAddr, PageNumber); //读取主要函数,也需要修改

/*判断读回的数据与写入的数据是否一致*/

for(j = 0; j < BUFFER_SIZE; j++)

{

if(TxBuffer[j] != RxBuffer[j])

{

WriteReadStatus++;

}

}

if (WriteReadStatus == 0)

{

printf("\n\r Nand Flash读写访问成功");

GPIO_ResetBits(GPIO_LED, DS2_PIN);

}

else

{

printf("\n\r Nand Flash读写访问失败");

printf("0x%x",WriteReadStatus);

GPIO_ResetBits(GPIO_LED, DS3_PIN);

}

}

else

{

printf("\n\r 没有检测到Nand Flash的ID");

GPIO_ResetBits(GPIO_LED, DS4_PIN);

}

复制代码

fsmc_nand.c文件:

void NAND_Init(void)

{

GPIO_InitTypeDef GPIO_InitStructure;

FSMC_NAND_PCCARDTimingInitTypeDef p;

FSMC_NANDInitTypeDef FSMC_NANDInitStructure;

/*FSMC总线使用的GPIO组时钟使能*/

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD | RCC_APB2Periph_GPIOE |

RCC_APB2Periph_GPIOF | RCC_APB2Periph_GPIOG, ENABLE);

/*FSMC CLE, ALE, D0->D3, NOE, NWE and NCE2初始化,推挽复用输出*/

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11 | GPIO_Pin_12 | GPIO_Pin_14 | GPIO_Pin_15 |

GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_4 | GPIO_Pin_5 |

GPIO_Pin_7;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

GPIO_Init(GPIOD, &GPIO_InitStructure);

/*FSMC数据线FSMC_D[4:7]初始化,推挽复用输出*/

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9 | GPIO_Pin_10;

GPIO_Init(GPIOE, &GPIO_InitStructure);

/*FSMC NWAIT初始化,输入上拉*/

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;

GPIO_Init(GPIOD, &GPIO_InitStructure);

/*FSMC INT2初始化,输入上拉*/

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;

GPIO_Init(GPIOG, &GPIO_InitStructure);

/*--------------FSMC 总线 存储器参数配置------------------------------*/

p.FSMC_SetupTime = 0x1; //建立时间

p.FSMC_WaitSetupTime = 0x3; //等待时间

p.FSMC_HoldSetupTime = 0x2; //保持时间

p.FSMC_HiZSetupTime = 0x1; //高阻建立时间

FSMC_NANDInitStructure.FSMC_Bank = FSMC_Bank2_NAND; //使用FSMC BANK2

FSMC_NANDInitStructure.FSMC_Waitfeature = FSMC_Waitfeature_Enable; //使能FSMC的等待功能

FSMC_NANDInitStructure.FSMC_MemoryDataWidth = FSMC_MemoryDataWidth_8b; //NAND Flash的数据宽度为8位

FSMC_NANDInitStructure.FSMC_ECC = FSMC_ECC_Enable; //使能ECC特性

FSMC_NANDInitStructure.FSMC_ECCPageSize = FSMC_ECCPageSize_2048Bytes; //ECC页大小2048

FSMC_NANDInitStructure.FSMC_TCLRSetupTime = 0x00;

FSMC_NANDInitStructure.FSMC_TARSetupTime = 0x00;

FSMC_NANDInitStructure.FSMC_CommonSpaceTimingStruct = &p;

FSMC_NANDInitStructure.FSMC_AttributeSpaceTimingStruct = &p;

FSMC_NANDInit(&FSMC_NANDInitStructure);

/*!使能FSMC BANK2 */

FSMC_NANDCmd(FSMC_Bank2_NAND, ENABLE);

}

复制代码

void NAND_ReadID(NAND_IDTypeDef* NAND_ID)

{

uint32_t data = 0;

/*!< Send Command to the command area */

*(__IO uint8_t *)(Bank_NAND_ADDR | CMD_AREA) = 0x90;

*(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = 0x00;

/*!< Sequence to read ID from NAND flash */

data = *(__IO uint32_t *)(Bank_NAND_ADDR | DATA_AREA);

NAND_ID->Maker_ID = ADDR_1st_CYCLE (data);//四个周期读取四个ID

NAND_ID->Device_ID = ADDR_2nd_CYCLE (data);

NAND_ID->Third_ID = ADDR_3rd_CYCLE (data);

NAND_ID->Fourth_ID = ADDR_4th_CYCLE (data);

}

复制代码

uint32_t NAND_WriteSmallPage(uint8_t *pBuffer, NAND_ADDRESS Address, uint32_t NumPageToWrite)

{//传入参数:写入数据,写入初始地址,要写几页

uint32_t index = 0x00, numpagewritten = 0x00, addressstatus = NAND_VALID_ADDRESS;

uint32_t status = NAND_READY, size = 0x00;

while((NumPageToWrite != 0x00) && (addressstatus == NAND_VALID_ADDRESS) && (status == NAND_READY))

{

/*!< Page write command and address */

*(__IO uint8_t *)(Bank_NAND_ADDR | CMD_AREA) = NAND_CMD_AREA_A;

*(__IO uint8_t *)(Bank_NAND_ADDR | CMD_AREA) = NAND_CMD_WRITE0;

*(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = 0x00;

*(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = 0x00;//添加此句

*(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = ADDR_1st_CYCLE(ROW_ADDRESS);

*(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = ADDR_2nd_CYCLE(ROW_ADDRESS);

// *(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = ADDR_3rd_CYCLE(ROW_ADDRESS);//原版有此句

/*!< Calculate the size */

size = NAND_PAGE_SIZE + (NAND_PAGE_SIZE * numpagewritten);//统计写入数目

/*!< Write data */

for(; index < size; index++)

{

*(__IO uint8_t *)(Bank_NAND_ADDR | DATA_AREA) = pBuffer[index];

}

*(__IO uint8_t *)(Bank_NAND_ADDR | CMD_AREA) = NAND_CMD_WRITE_TRUE1;

/*!< Check status for successful operation */

status = NAND_GetStatus();

if(status == NAND_READY)

{

numpagewritten++;

NumPageToWrite--;

/*!< Calculate Next small page Address */

addressstatus = NAND_AddressIncrement(&Address);

}

}

return (status | addressstatus);

}

复制代码

读取函数同理修改

uint32_t NAND_EraseBlock(NAND_ADDRESS Address)

{

*(__IO uint8_t *)(Bank_NAND_ADDR | CMD_AREA) = NAND_CMD_ERASE0;

*(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = ADDR_1st_CYCLE(ROW_ADDRESS);

*(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = ADDR_2nd_CYCLE(ROW_ADDRESS);

// *(__IO uint8_t *)(Bank_NAND_ADDR | ADDR_AREA) = ADDR_3rd_CYCLE(ROW_ADDRESS);//两次即可

*(__IO uint8_t *)(Bank_NAND_ADDR | CMD_AREA) = NAND_CMD_ERASE1;

return (NAND_GetStatus());

}

复制代码

fsmc_nand.h文件:

#define NAND_PAGE_SIZE ((uint16_t)0x0800) /* 512 bytes per page w/o Spare Area *///每页2K

#define NAND_BLOCK_SIZE ((uint16_t)0x0040) /* 32x512 bytes pages per block *///64个页

#define NAND_ZONE_SIZE ((uint16_t)0x0400) /* 1024 Block per zone *///1024个快

#define NAND_SPARE_AREA_SIZE ((uint16_t)0x0040) /* last 16 bytes as spare area */

#define NAND_MAX_ZONE ((uint16_t)0x0001) /* 4 zones of 1024 block */

复制代码

修改完即可实现512B至2K每页的变更
本文参考:器件手册,蔡于清——NAND器件读写操作,百度搜索 QQ458729218 附件:有效程序,器件手册
内容来自用户分享和网络整理,不保证内容的准确性,如有侵权内容,可联系管理员处理 点击这里给我发消息
标签: