【GD32F303红枫派开发板使用手册】第二十讲 SPI-SPI NAND FLASH读写实验

20.1实验内容

通过本实验主要学习以下内容：

• SPI通信协议，参考19.2.1东方红开发板使用手册
• GD32F303 SPI操作方式，参考19.2.2东方红开发板使用手册
• NAND FLASH基本原理
• SPI NAND介绍
• 使用GD32F303 SPI接口实现对GD5F1GQ5UEYIGY的读写操作

20.2实验原理

20.2.1NAND FLASH基本原理

NAND Flash和NOR Flash都是两种非易失性存储器，其读写速度、读写方式，存储区结构、成本、容量、擦写寿命都有很大区别。NAND在寿命、速度、读写方式上都不如NOR，但在成本和容量上有很大区别，故而决定了大容量数据存储是NAND的主要应用领域，而快速启动、快速数据读取等场景是NOR的主要应用领域。而SPI是目前NAND和NOR的主要通信接口形式，降低了器件体积，标准化了器件接口。

• NAND Flash结构示例

如上图所示，以GD5F1GQ5UEYIGY为例，一个1Gb的存储结构下是由1024个block组成，每个block又64page组成，每个page是2K Main Area+Spare Area(ECC ON:64B;ECC OFF:128B)组成。

NAND的擦除单位是blocks，写入单位是page，所以寻址的方式上和nor是有本质区别的，需要按blocks、page、page字节偏移地址进行一个数据的寻址。

20.2.2SPI NAND介绍

SPI NAND简化了NAND的接口设计和尺寸，SPI接口更是降低了主控对接口的要求，同时内置ECC。下图是GD5F1GQ5UEYIGY的命令表，常用的命令为擦除、编程、读取命令。

• block擦除命令

• 编程
• 编程流程

1. 先用数据缓存写入指令将数据写入缓冲区
2. 然后发送写使能命令，并确认写使能成功
3. 然后发送数据载入命令执行缓冲区数据到FLASH的写
4. 最后查询读寄存器确认P_FAIL是否有错，OIP是否完成

注意(84h/C4h/34h) 和(FFh)指令是不会清除缓存中的内容的，所以下次编程时要注意是否缓存区都是需要更新的数据，所以必须是一次更新整个缓冲区，不要部分更新。

编程page地址按照块的顺序

• 数据缓存写入命令

• 数据载入命令

• 读取
• 读取流程

1. 读需要先通过读cache命令从FLASH中读出数据到缓存中
2. 然后通过读cache指令从缓冲区中开始读出数据

读到2048+128后绕回从0开始继续。

20.3硬件设计

红枫派开发板SPI——NAND FLASH的硬件设计如下：

从图中可以看出，本实验使用的是普通单线SPI，GD5F1GQ5UEYIGY的片选由GD32F303ZET6的PG13控制（因PG14不是SPI的NSS管脚，所以本实验用主机NSS软件模式,，通过普通IO控制片选），GD25Q32ESIGR的SO、SI和SCLK分别和GD32F303ZET6的PB4（SPI2_MISO）、PB5（SPI2_MOSI）以及PB3（SPI2_CLK）相连。

20.4代码解析

20.4.1SPI初始化和读写BYTE函数实现

SPI初始化配置流程可参考19.4.1东方红开发板使用手册；

SPI读写BYTE函数实现可参考19.4.2东方红开发板使用手册；

20.4.2SPI NAND FLASH BSP驱动层实现

操作NAND FLASH的函数都定义在bsp层文件bsp_spi_nand.c中，这个文件中定义的函数都是针对NAND FLASH命令来实现的，我们选取几个函数进行介绍。

• NOR FLASH按block擦除函数bsp_nandflash_block_erase，输入block号即可擦除；该函数流程是：使能NAND FLASH的写功能->向NOR FLASH发送block擦除指令0xD8->发送左移6位的Block NO->查询OIP标志等待完成

C /*! \brief erase the nandflash blcok \param[in] block_No:the serial number of erase block \param[out] none \retval SPI_NAND_FAIL: erase the nandflash block fail \retval SPI_NAND_SUCCESS: erase the nandflash block success */ uint8_t bsp_spi_nandflash_block_erase(uint32_t block_No) { uint8_t result = SPI_NAND_SUCCESS; block_No<<=6;        //block_No=block_No*64 bsp_spi_nandflash_write_enable(); /* select the flash: chip select low */ bsp_spi_nand_cs_low(); /* send "ERASE BLOCK" command */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,SPI_NAND_BLOCK_ERASE); /* send the address of memory */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,(block_No>>16)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,(block_No>>8)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,block_No&0xFF); /* deselect the flash: chip select high */ bsp_spi_nand_cs_high(); while(bsp_spi_nandflash_get_status_flag(OIP)==SPI_NAND_BUSY); /* check program result */ return result; }

• NOR FLASH按page写入函数bsp_nandflash_page_program，输入待写入数据指针、block号、page号；该函数流程是：
• 写缓冲区，实现流程：向NOR FLASH发送写缓冲区指令0x02->发送写入的page偏移地址->发送待写入数据
• 载入数据到page，实现流程：使能NAND FLASH的写功能->发送载入命令0x10->发送写入的page号
• 查询OIP标志等待完成

C /*! \brief send the program load command,write data to cache \param[in] buffer: the data of array \param[in] address_in_page: the address in nandflash page \param[in] byte_cnt: the number of data \param[out] none \retval none */ void bsp_spi_nandflash_program_load(uint8_t *buffer,uint16_t address_in_page,uint32_t byte_cnt) { uint32_t i=0; /* select the flash: chip select low */ bsp_spi_nand_cs_low(); #ifdef SPI_NANDFLASH /* send "PAGE READ" command */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,SPI_NAND_PAGE_LOAD); /* send the serial number of page */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,(address_in_page>>8)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,address_in_page&0xFF); #endif /* deselect the flash: chip select high */ for(i=0;i driver_spi_master_transmit_receive_byte(&BOARD_SPI,*buffer++); } //printf("cache program %x %x\n\r",m32record[0],m32record[1]); bsp_spi_nand_cs_high(); qspi_disable(BOARD_SPI.spi_x); } /*! \brief send the program excute command \param[in] page_No: the serial number of nandflash page \param[out] none \retval none */ void bsp_spi_nandflash_program_execute(uint32_t page_No) { /* enable the write access to the flash */ bsp_spi_nandflash_write_enable(); /* select the flash: chip select low */ bsp_spi_nand_cs_low(); /* send "PAGE READ" command */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,SPI_NAND_PROGRAM_EXEC); /* send the serial number of page */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,(page_No>>16)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,(page_No>>8)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,page_No&0xFF); /* deselect the flash: chip select high */ bsp_spi_nand_cs_high(); } /*! \brief write the data to nandflash \param[in] *buffer:the data of array \param[in] page_No: the serial number of nandflash page \param[in] address_in_page: the address of nandflash page \param[in] byte_cnt:the number of data \param[out] none \retval SPI_NAND_FAIL,SPI_NAND_SUCCESS */ uint8_t spi_nandflash_write_data(uint8_t *buffer,uint32_t page_No,uint16_t address_page,uint32_t byte_cnt) { /*sned the program load command,write data to cache*/ bsp_spi_nandflash_program_load(buffer, address_page, byte_cnt); /*sned the program excute command*/ bsp_spi_nandflash_program_execute(page_No); /* Check program result */ while(bsp_spi_nandflash_get_status_flag(OIP)==SPI_NAND_BUSY); #ifdef WRITE_PAGE_VERIFY_EN spi_nandflash_read_data (tem_buffer,page_No, address_page, byte_cnt); if (memcmp(tem_buffer, buffer, byte_cnt) != 0){ return SUCCESS; } #endif return 1; }

• NOR FLASH按page读取函数spi_nandflash_read_data，输入读取数据指针、page号、page内地址偏移、读取长度；该函数流程是：
• 读page到缓冲区，实现流程：向NOR FLASH发送写缓冲区指令0x13->送要读取的page号
• 等待OIP标志（NAND读取page到缓冲区完成）
• 从缓冲区读取数据，实现流程：发送读cache命令0x03->发送要读取的page地址偏移->读取所需长度的数据
• 查询是否有ecc错误

C /*! \brief send the read page command \param[in] page_No: the serial number of nandflash page \param[out] none \retval none */ void bsp_spi_nandflash_page_read(uint32_t page_No) { /* select the flash: chip select low */ bsp_spi_nand_cs_low(); /* send "PAGE READ" command */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,SPI_NAND_PAGE_READ); /* send the serial number of page */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,(page_No>>16)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,(page_No>>8)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,page_No&0xFF); /* deselect the flash: chip select high */ bsp_spi_nand_cs_high(); } /*! \brief send the read cache command \param[in] buffer: a pointer to the array \param[in] address_in_page: the address in nandflash page \param[in] byte_cnt: the number of data \param[out] none \retval none */ void bsp_spi_nandflash_read_cache(uint8_t *buffer,uint16_t address_in_page,uint32_t byte_cnt) { uint32_t i=0; /* select the flash: chip select low */ bsp_spi_nand_cs_low(); #ifdef SPI_NANDFLASH /* send "PAGE READ" command */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,SPI_NAND_READ_CACHE); //driver_spi_master_transmit_receive_byte(&BOARD_SPI,DUMMY_BYTE);//Q4UC ++ Q5 -- /* send the address of page */ driver_spi_master_transmit_receive_byte(&BOARD_SPI,(address_in_page>>8)&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,address_in_page&0xFF); driver_spi_master_transmit_receive_byte(&BOARD_SPI,DUMMY_BYTE);//Q4UC -- Q5 ++ #endif for(i=0;i *buffer++=driver_spi_master_transmit_receive_byte(&BOARD_SPI,DUMMY_BYTE); } /* deselect the flash: chip select high */ bsp_spi_nand_cs_high(); qspi_disable(BOARD_SPI.spi_x); } /*! \brief read the data from nandflash \param[in] *buffer:the data of array \param[in] page_No: the serial number of nandflash page \param[in] address_in_page: the address in nandflash page \param[in] byte_cnt:the number of data \param[out] none \retval SPI_NAND_FAIL,SPI_NAND_SUCCESS */ uint8_t spi_nandflash_read_data(uint8_t *buffer,uint32_t page_No,uint32_t address_in_page,uint32_t byte_cnt) { uint8_t result = SPI_NAND_SUCCESS; uint8_t status = 0; uint8_t retrycnt = 0; /* the capacity of page must be equal or greater than the taotal of address_in_page and byte_cnt */ if((address_in_page+byte_cnt)>SPI_NAND_PAGE_TOTAL_SIZE){ return SPI_NAND_FAIL; } ReadRetry: /* send the read page command */ bsp_spi_nandflash_page_read(page_No); /* wait for NANDFLASH is ready */ while(bsp_spi_nandflash_get_status_flag(OIP)==SPI_NAND_BUSY); /* read data from cache */ bsp_spi_nandflash_read_cache(buffer, address_in_page, byte_cnt); bsp_spi_nandflash_get_feature( STATUS, &status ); if(( (status & ECCS0) == 0 )&&( (status & ECCS1) == ECCS1 )){ //UECC if(retrycnt < 3) { retrycnt++; printf("\rReadretry:%x %x\n",retrycnt,page_No); goto ReadRetry; } else { printf("\rRead Fail %x\n",page_No); } } return result; }

20.4.3main函数实现

main函数中实现了擦除一个block，并对该block中的page进行写入操作，然后读取后进行数据对比校验的功能。

C /*! * 说明 main函数 * 输入 无 * 输出 无 * 返回值 无 */ int main(void) { //延时、共用驱动部分初始化 driver_init(); //初始化LED组和默认状态 bsp_led_group_init(); bsp_led_on(&LED0); bsp_led_off(&LED1); //初始化UART打印 bsp_uart_init(&BOARD_UART); //初始化SPI bsp_spi_init(&BOARD_SPI); //初始化SPI NAND bsp_spi_nand_init(); printf("\n\rSPI NAND:GD5F1G configured...\n\r"); //读取flash id flash_id=bsp_spi_nandflash_read_id(); printf("\n\rThe NAND_ID:0x%X\n\r",flash_id); //比对flash id是否一致 if(NAND_ID != flash_id) { printf("\n\r\n\rWrite to tx_buffer:\n\r\n\r"); //准备数据 for(uint16_t i = 0; i < BUFFER_SIZE; i ++){ tx_buffer[i] = i; printf("0x%02X ",tx_buffer[i]); if(15 == i%16) printf("\n\r"); } printf("\n\r\n\rRead from rx_buffer:\n\r"); //擦除要写入的block bsp_nandflash_block_erase(0); //写入数据 bsp_nandflash_page_program((uint8_t*)tx_buffer,0,0,0); //回读写入数据 bsp_nandflash_page_read(rx_buffer,0,0); /* printf rx_buffer value */ for(uint16_t i = 0; i <= 255; i ++){ printf("0x%02X ", rx_buffer[i]); if(15 == i%16) printf("\n\r"); } //比较回读和写入数据 if(ERROR == memory_compare(tx_buffer,rx_buffer,BUFFER_SIZE)){ printf("Err:Data Read and Write aren't Matching.\n\r"); /* spi flash read id fail */ printf("\n\rSPI nand: Read ID Fail!\n\r"); //写入错误 /* turn off all leds */ bsp_led_on(&LED0); /* turn off all leds */ bsp_led_on(&LED1); while(1); }else{ printf("\n\rSPI-GD5F1G Test Passed!\n\r"); } }else{ //ID读取错误 /* spi flash read id fail */ printf("\n\rSPI Nand:Read ID Fail!\n\r"); /* turn off all leds */ bsp_led_on(&LED0); /* turn off all leds */ bsp_led_on(&LED1); while(1); } while(1){ /* turn off all leds */ bsp_led_toggle(&LED0); /* turn off all leds */ bsp_led_toggle(&LED1); delay_ms(200); } }

20.5实验结果

nand读取到正确ID后开始擦写读流程，如果ID读取错误或者数据比对不通过点亮LED0，熄灭LED1，如果比对通过则交替闪烁LED0和LED1，通过USB转串口可以看到打印结果。

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