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(5s4、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:1. #define BUFFER_SIZE 0x2000 //此部分定义缓冲区大小,即一次写入的数据2. #define NAND_HY_MakerID 0xAD //NAND厂商号3. #define NAND_HY_DeviceID 0xF1 //NAND器件号4. /*配置与SRAM连接的FSMC BANK2 NAND*/5. NAND_Init(;6. /*读取Nand Flash ID并打印*/7. NAND_ReadID(&NAND_ID;复制代码Tips:NAND器件的ID包含四部分:1st Manufacturer Code2nd Device Identifier3rd Internal chip number, cell Type, Number of Simultaneously Programmedpages.4th Page size, spare size, Block size, Organization1. if((NAND_ID.Maker_ID == NAND_HY_MakerID && (NAND_ID.Device_ID == NAND_HY_DeviceID //判断器件符合2. {3. /*设置NAND FLASH的写地址*/4. WriteReadAddr.Zone = 0x00;5. WriteReadAddr.Block = 0x00;6. WriteReadAddr.Page = 0x05;7. /*擦除待写入数据的块*/8. status = NAND_EraseBlock(WriteReadAddr; //写入前必须擦出9. /*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*/10. Fill_Buffer(TxBuffer, BUFFER_SIZE , 0x25; //填充数据以测试11. /*将数据写入到Nand Flash中。

WriteReadAddr:读写的起始地址*/12. status = NAND_WriteSmallPage(TxBuffer, WriteReadAddr, PageNumber; //主要写入函数,此部分默认为小页需要修改13. /*从Nand Flash中读回刚写入的数据。

riteReadAddr:读写的起始地址*/14. status = NAND_ReadSmallPage (RxBuffer, WriteReadAddr, PageNumber; //读取主要函数,也需要修改15.16. /*判断读回的数据与写入的数据是否一致*/17. for(j = 0; j < BUFFER_SIZE; j++18. {19. if(TxBuffer[j] != RxBuffer[j]20. {21. WriteReadStatus++;22. }23. }24.25. if (WriteReadStatus == 026. {27. printf("\n\r Nand Flash读写访问成功";28. GPIO_ResetBits(GPIO_LED, DS2_PIN;29. }30. else31. {32. printf("\n\r Nand Flash读写访问失败";33. printf("0x%x",WriteReadStatus;34.35. GPIO_ResetBits(GPIO_LED, DS3_PIN;36.37. }38. }39. else40. {41. printf("\n\r 没有检测到Nand Flash的ID";42. GPIO_ResetBits(GPIO_LED, DS4_PIN;43. }复制代码fsmc_nand.c文件:1. void NAND_Init(void2. {3. GPIO_InitTypeDef GPIO_InitStructure;4. FSMC_NAND_PCCARDTimingInitTypeDef p;5. FSMC_NANDInitTypeDef FSMC_NANDInitStructure;6.7. /*FSMC总线使用的GPIO组时钟使能*/8. RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD |RCC_APB2Periph_GPIOE |9. RCC_APB2Periph_GPIOF | RCC_APB2Periph_GPIOG, ENABLE;10.11. /*FSMC CLE, ALE, D0->D3, NOE, NWE and NCE2初始化,推挽复用输出*/12. GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11 | GPIO_Pin_12 | GPIO_Pin_14 | GPIO_Pin_15 |13. GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_4 | GPIO_Pin_5 |14. GPIO_Pin_7;15. GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;16. GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;17. GPIO_Init(GPIOD, &GPIO_InitStructure;18. /*FSMC数据线FSMC_D[4:7]初始化,推挽复用输出*/19. GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9 | GPIO_Pin_10;20. GPIO_Init(GPIOE, &GPIO_InitStructure;21. /*FSMC NWAIT初始化,输入上拉*/22. GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;23. GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;24. GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;25. GPIO_Init(GPIOD, &GPIO_InitStructure;26. /*FSMC INT2初始化,输入上拉*/27. GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;28. GPIO_Init(GPIOG, &GPIO_InitStructure;29. /*--------------FSMC 总线存储器参数配置------------------------------*/30. p.FSMC_SetupTime = 0x1; //建立时间31. p.FSMC_WaitSetupTime = 0x3; //等待时间32. p.FSMC_HoldSetupTime = 0x2; //保持时间33. p.FSMC_HiZSetupTime = 0x1; //高阻建立时间34. FSMC_NANDInitStructure.FSMC_Bank = FSMC_Bank2_NAND; //使用FSMC BANK235. FSMC_NANDInitStructure.FSMC_Waitfeature = FSMC_Waitfeature_Enable; //使能FSMC的等待功能36. FSMC_NANDInitStructure.FSMC_MemoryDataWidth =FSMC_MemoryDataWidth_8b; //NAND Flash的数据宽度为8位37. FSMC_NANDInitStructure.FSMC_ECC = FSMC_ECC_Enable; //使能ECC特性38. FSMC_NANDInitStructure.FSMC_ECCPageSize =FSMC_ECCPageSize_2048Bytes; //ECC页大小204839. FSMC_NANDInitStructure.FSMC_TCLRSetupTime = 0x00;40. FSMC_NANDInitStructure.FSMC_TARSetupTime = 0x00;41. FSMC_NANDInitStructure.FSMC_CommonSpaceTimingStruct = &p;42. FSMC_NANDInitStructure.FSMC_AttributeSpaceTimingStruct = &p;43. FSMC_NANDInit(&FSMC_NANDInitStructure;44. /*!使能FSMC BANK2 */45. FSMC_NANDCmd(FSMC_Bank2_NAND, ENABLE;46. }复制代码1. void NAND_ReadID(NAND_IDTypeDef* NAND_ID2. {3. uint32_t data = 0;4. /*!< Send Command to the command area */5. *(__IO uint8_t *(Bank_NAND_ADDR | CMD_AREA = 0x90;6. *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA = 0x00;7. /*!< Sequence to read ID from NAND flash */8. data = *(__IO uint32_t *(Bank_NAND_ADDR | DATA_AREA;9. NAND_ID->Maker_ID = ADDR_1st_CYCLE (data;//四个周期读取四个ID10. NAND_ID->Device_ID = ADDR_2nd_CYCLE (data;11. NAND_ID->Third_ID = ADDR_3rd_CYCLE (data;12. NAND_ID->Fourth_ID = ADDR_4th_CYCLE (data;13. }复制代码1. uint32_t NAND_WriteSmallPage(uint8_t *pBuffer, NAND_ADDRESS Address, uint32_t NumPageToWrite2. {//传入参数:写入数据,写入初始地址,要写几页3. uint32_t index = 0x00, numpagewritten = 0x00, addressstatus =NAND_VALID_ADDRESS;4. uint32_t status = NAND_READY, size = 0x00;5. while((NumPageToWrite != 0x00 && (addressstatus ==NAND_VALID_ADDRESS && (status == NAND_READY6. {7. /*!< Page write command and address */8. *(__IO uint8_t *(Bank_NAND_ADDR | CMD_AREA =NAND_CMD_AREA_A;9. *(__IO uint8_t *(Bank_NAND_ADDR | CMD_AREA = NAND_CMD_WRITE0;10. *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA = 0x00;11. *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA = 0x00;//添加此句12. *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA =ADDR_1st_CYCLE(ROW_ADDRESS;13. *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA =ADDR_2nd_CYCLE(ROW_ADDRESS;14. // *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA =ADDR_3rd_CYCLE(ROW_ADDRESS;//原版有此句15. /*!< Calculate the size */16. size = NAND_PAGE_SIZE + (NAND_PAGE_SIZE * numpagewritten;//统计写入数目17. /*!< Write data */18. for(; index < size; index++19. {20. *(__IO uint8_t *(Bank_NAND_ADDR | DATA_AREA = pBuffer[index];21. }22.23. *(__IO uint8_t *(Bank_NAND_ADDR | CMD_AREA =NAND_CMD_WRITE_TRUE1;24. /*!< Check status for successful operation */25. status = NAND_GetStatus(;26.27. if(status == NAND_READY28. {29. numpagewritten++;30. NumPageToWrite--;31. /*!< Calculate Next small page Address */32. addressstatus = NAND_AddressIncrement(&Address;33. }34. }35.36. return (status | addressstatus;37. }复制代码读取函数同理修改1. uint32_t NAND_EraseBlock(NAND_ADDRESS Address2. {3. *(__IO uint8_t *(Bank_NAND_ADDR | CMD_AREA = NAND_CMD_ERASE0;4. *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA =ADDR_1st_CYCLE(ROW_ADDRESS;5. *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA =ADDR_2nd_CYCLE(ROW_ADDRESS;6. // *(__IO uint8_t *(Bank_NAND_ADDR | ADDR_AREA =ADDR_3rd_CYCLE(ROW_ADDRESS;//两次即可7. *(__IO uint8_t *(Bank_NAND_ADDR | CMD_AREA = NAND_CMD_ERASE1;8. return (NAND_GetStatus(;9. }复制代码 fsmc_nand.h 文件： 1. 2. 3. 4. 5. #define NAND_PAGE_SIZE #define NAND_BLOCK_SIZE #define NAND_ZONE_SIZE #defineNAND_SPARE_AREA_SIZE #define NAND_MAX_ZONE ((uint16_t0x0800 /* 512 bytes per page w/o Spare Area */// 每页 2K ((uint16_t0x0040 /* 32x512 bytes pages per block *///64 个页 ((uint16_t0x0400 /* 1024 Block per zone *///1024 个快((uint16_t0x0040 /* last 16 bytes as spare area */ ((uint16_t0x0001 /* 4 zones of 1024 block */ 复制代码修改完即可实现 512B 至 2K 每页的变更。