本文原創於觀海聽濤,原作者版權所有,轉載請注明出處。 近幾天開發項目需要用到STM32驅動NAND FLASH,但由於開發板例程以及固件庫是用於小頁(512B),我要用到的FLASH為1G bit的大頁(2K),多走了兩天彎路。以下筆記將說明如何將默認固件庫修改為大頁模式以驅動大容量NAND,並作驅動。
本文硬件:控制器:STM32F103ZET6,存儲器:HY27UF081G2A
首先說一下NOR與NAND存儲器的區別,此類區別網上有很多,在此僅大致說明:
1、Nor讀取速度比NAND稍快 2、Nand寫入速度比Nor快很多 3、NAND擦除速度(4ms)遠快於Nor(5s) 4、Nor 帶有SRAM接口,有足夠的地址引腳來尋址,可以很輕松的掛接到CPU地址和數據總線上,對CPU要求低 5、NAND用八個(或十六個)引腳串行讀取數據,數據總線地址總線復用,通常需要CPU支持驅動,且較為復雜 6、Nor主要占據1-16M容量市場,並且可以片內執行,適合代碼存儲 7、NAND占據8-128M及以上市場,通常用來作數據存儲 8、NAND便宜一些 9、NAND壽命比Nor長 10、NAND會產生壞塊,需要做壞塊處理和ECC 更詳細區別請繼續百度,以上內容部分摘自神舟三號開發板手冊
下面是NAND的存儲結構:
由此圖可看出NAND存儲結構為立體式 正如硬盤的盤片被分為磁道,每個磁道又分為若干扇區,一塊nand flash也分為若干block,每個block分為如干page。一般而言,block、page之間的關系隨着芯片的不同而不同。 需要注意的是,對於flash的讀寫都是以一個page開始的,但是在讀寫之前必須進行flash的擦寫,而擦寫則是以一個block為單位的。 我們這次使用的HY27UF081G2A其PDF介紹: Memory Cell Array = (2K+64) Bytes x 64 Pages x 1,024 Blocks 由此可見,該NAND每頁2K,共64頁,1024塊。其中:每頁中的2K為主容量Data Field,64bit為額外容量Spare Field。Spare Field用於存貯檢驗碼和其他信息用的,並不能存放實際的數據。由此可算出系統總容量為2K*64*1024=134217728個byte,即1Gbit。 NAND閃存顆粒硬件接口: 由此圖可見,此顆粒為八位總線,地址數據復用,芯片為SOP48封裝。
軟件驅動:(此部分寫的是偽碼,僅用於解釋含義,可用代碼參見附件) 主程序:
- #define BUFFER_SIZE 0x2000 //此部分定義緩沖區大小,即一次寫入的數據
- #define NAND_HY_MakerID 0xAD //NAND廠商號
- #define NAND_HY_DeviceID 0xF1 //NAND器件號
- /*配置與SRAM連接的FSMC BANK2 NAND*/
- NAND_Init();
- /*讀取Nand Flash ID並打印*/
- NAND_ReadID(&NAND_ID);
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)) //判斷器件符合
- {
- /*設置NAND FLASH的寫地址*/
- WriteReadAddr.Zone = 0x00;
- WriteReadAddr.Block = 0x00;
- WriteReadAddr.Page = 0x05;
- /*擦除待寫入數據的塊*/
- status = NAND_EraseBlock(WriteReadAddr); //寫入前必須擦出
- /*將寫Nand Flash的數據BUFFER填充為從0x25開始的連續遞增的一串數據 */
- Fill_Buffer(TxBuffer, BUFFER_SIZE , 0x25); //填充數據以測試
- /*將數據寫入到Nand Flash中。WriteReadAddr:讀寫的起始地址*/
- status = NAND_WriteSmallPage(TxBuffer, WriteReadAddr, PageNumber); //主要寫入函數,此部分默認為小頁需要修改
- /*從Nand Flash中讀回剛寫入的數據。riteReadAddr:讀寫的起始地址*/
- status = NAND_ReadSmallPage (RxBuffer, WriteReadAddr, PageNumber); //讀取主要函數,也需要修改
- /*判斷讀回的數據與寫入的數據是否一致*/
- for(j = 0; j < BUFFER_SIZE; j++)
- {
- if(TxBuffer[j] != RxBuffer[j])
- {
- WriteReadStatus++;
- }
- }
- if (WriteReadStatus == 0)
- {
- printf("\n\r Nand Flash讀寫訪問成功");
- GPIO_ResetBits(GPIO_LED, DS2_PIN);
- }
- else
- {
- printf("\n\r Nand Flash讀寫訪問失敗");
- printf("0x%x",WriteReadStatus);
- GPIO_ResetBits(GPIO_LED, DS3_PIN);
- }
- }
- else
- {
- printf("\n\r 沒有檢測到Nand Flash的ID");
- GPIO_ResetBits(GPIO_LED, DS4_PIN);
- }
fsmc_nand.c文件:
- void NAND_Init(void)
- {
- GPIO_InitTypeDef GPIO_InitStructure;
- FSMC_NAND_PCCARDTimingInitTypeDef p;
- FSMC_NANDInitTypeDef FSMC_NANDInitStructure;
- /*FSMC總線使用的GPIO組時鍾使能*/
- 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,推挽復用輸出*/
- 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數據線FSMC_D[4:7]初始化,推挽復用輸出*/
- 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,輸入上拉*/
- 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,輸入上拉*/
- GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
- GPIO_Init(GPIOG, &GPIO_InitStructure);
- /*--------------FSMC 總線 存儲器參數配置------------------------------*/
- p.FSMC_SetupTime = 0x1; //建立時間
- p.FSMC_WaitSetupTime = 0x3; //等待時間
- p.FSMC_HoldSetupTime = 0x2; //保持時間
- p.FSMC_HiZSetupTime = 0x1; //高阻建立時間
- 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的數據寬度為8位
- FSMC_NANDInitStructure.FSMC_ECC = FSMC_ECC_Enable; //使能ECC特性
- FSMC_NANDInitStructure.FSMC_ECCPageSize = FSMC_ECCPageSize_2048Bytes; //ECC頁大小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);
- }
- 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);//四個周期讀取四個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);
- }
- uint32_t NAND_WriteSmallPage(uint8_t *pBuffer, NAND_ADDRESS Address, uint32_t NumPageToWrite)
- {//傳入參數:寫入數據,寫入初始地址,要寫幾頁
- 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);//統計寫入數目
- /*!< 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);
- }
讀取函數同理修改
- 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);//兩次即可
- *(__IO uint8_t *)(Bank_NAND_ADDR | CMD_AREA) = NAND_CMD_ERASE1;
- return (NAND_GetStatus());
- }
fsmc_nand.h文件:
- #define NAND_PAGE_SIZE ((uint16_t)0x0800) /* 512 bytes per page w/o Spare Area *///每頁2K
- #define NAND_BLOCK_SIZE ((uint16_t)0x0040) /* 32x512 bytes pages per block *///64個頁
- #define NAND_ZONE_SIZE ((uint16_t)0x0400) /* 1024 Block per zone *///1024個快
- #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 */
修改完即可實現512B至2K每頁的變更
本文參考:器件手冊,蔡於清——NAND器件讀寫操作,百度搜索 QQ458729218 附件:有效程序,器件手冊