“RA MCU众测宝典”中I2C/SPI通信与显示驱动专题更新了。这次我们聚焦瑞萨【CPKCOR-RA8D1B核心板】开发板,一步步实现QSPI读取外部Flash。
开启宝典
QSPI是Queued SPI的简写,是Motorola公司推出的SPI接口的扩展,比SPI应用更加广泛。在SPI协议的基础上,Motorola公司对其功能进行了增强,增加了队列传输机制,推出了队列串行外围接口协议(即QSPI协议)。
QSPI是一种专用的通信接口,连接单、双或四(条数据线)SPI Flash存储介质。QSPI是一个内存控制器,用于连接具有SPI兼容接口的串行ROM(非易失性存储器)。
我们看一下核心板上的外扩Flash:

外扩的Flash的型号是AT25SF128B。
QSPI使用6个信号连接Flash,分别是四个数据线QIO0~QIO3,一个时钟输出CLK,一个片选输出(低电平有效)QSSL,它们的作用介绍如下:
QSSL:片选输出(低电平有效),适用于FLASH 1。如果QSPI始终在双闪存模式下工作,则其也可用于FLASH 2从设备选择信号线。QSPI通讯以QSSL线置低电平为开始信号,以QSSL线被拉高作为结束信号。
CLK:时钟输出,适用于两个存储器,用于通讯数据同步。它由通讯主机产生,决定了通讯的速率,不同的设备支持的最高时钟频率不一样,两个设备之间通讯时,通讯速率受限于低速设备。
QIO0QIO0~QIO3:四线模式中为双向IO。
接下来进行软件配置:
添加OSPI功能模块:
接下来我们配置一下引脚:

一共是6个引脚,接下来配置模块信息:
下面是部分Flash的命令,我们可以初始化这些内容:

接下来我们代码测试一下QSPI的功能。
我们定义了一些基础功能测试:
左右滑动查看完整内容
uint8_tg_read_data [OSPI_B_APP_DATA_SIZE] = {RESET_VALUE};
uint8_tg_write_data [OSPI_B_APP_DATA_SIZE] = {0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F,0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17,0x18,0x19,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F,0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,0x3C,0x3D,0x3E,0x3F,};spi_flash_direct_transfer_tg_ospi_b_direct_transfer [OSPI_B_TRANSFER_MAX] ={/* Transfer structure for SPI mode */ [OSPI_B_TRANSFER_WRITE_ENABLE_SPI] = { .command = OSPI_B_COMMAND_WRITE_ENABLE_SPI, .address = OSPI_B_ADDRESS_DUMMY, .data = OSPI_B_DATA_DUMMY, .command_length = OSPI_B_COMMAND_LENGTH_SPI, .address_length = OSPI_B_ADDRESS_LENGTH_ZERO, .data_length = OSPI_B_DATA_LENGTH_ZERO, .dummy_cycles = OSPI_B_DUMMY_CYCLE_WRITE_SPI }, [OSPI_B_TRANSFER_READ_STATUS_SPI] = { .command = OSPI_B_COMMAND_READ_STATUS_SPI, .address = OSPI_B_ADDRESS_DUMMY, .data = OSPI_B_DATA_DUMMY, .command_length = OSPI_B_COMMAND_LENGTH_SPI, .address_length = OSPI_B_ADDRESS_LENGTH_ZERO, .data_length = OSPI_B_DATA_LENGTH_ONE, .dummy_cycles = OSPI_B_DUMMY_CYCLE_READ_STATUS_SPI }, [OSPI_B_TRANSFER_READ_DEVICE_ID_SPI] = { .command = OSPI_B_COMMAND_READ_DEVICE_ID_SPI, //0x9f .address = OSPI_B_ADDRESS_DUMMY, //0 .data = OSPI_B_DATA_DUMMY, //0 .command_length = OSPI_B_COMMAND_LENGTH_SPI, //1 .address_length = OSPI_B_ADDRESS_LENGTH_ZERO, //0 .data_length = OSPI_B_DATA_LENGTH_FOUR, //4 .dummy_cycles = OSPI_B_DUMMY_CYCLE_READ_STATUS_SPI //0 }};fsp_err_tospi_b_read_device_id(uint32_t*constp_id){fsp_err_t err = FSP_SUCCESS;spi_flash_direct_transfer_ttransfer = {RESET_VALUE};/* Read and check flash device ID */ transfer = g_ospi_b_direct_transfer[OSPI_B_TRANSFER_READ_DEVICE_ID_SPI]; err =R_OSPI_B_DirectTransfer(&g_qspi0_flash_ctrl, &transfer, SPI_FLASH_DIRECT_TRANSFER_DIR_READ);if(err!=FSP_SUCCESS) {printf("R_OSPI_B_DirectTransfer API FAILED \r\n"); }/* Get flash device ID */ *p_id = transfer.data;returnerr;}staticfsp_err_tospi_b_write_enable(void){fsp_err_t err = FSP_SUCCESS;spi_flash_direct_transfer_ttransfer = {RESET_VALUE};/* Transfer write enable command */ transfer = g_ospi_b_direct_transfer[OSPI_B_TRANSFER_WRITE_ENABLE_SPI]; err =R_OSPI_B_DirectTransfer(&g_qspi0_flash_ctrl, &transfer, SPI_FLASH_DIRECT_TRANSFER_DIR_WRITE); assert(FSP_SUCCESS == err);/* Read Status Register */ transfer = g_ospi_b_direct_transfer[OSPI_B_TRANSFER_READ_STATUS_SPI]; err =R_OSPI_B_DirectTransfer(&g_qspi0_flash_ctrl, &transfer, SPI_FLASH_DIRECT_TRANSFER_DIR_READ); assert(FSP_SUCCESS == err);/* Check Write Enable bit in Status Register */if(OSPI_B_WEN_BIT_MASK != (transfer.data & OSPI_B_WEN_BIT_MASK)) {printf("Write enable FAILED\r\n"); }returnerr;}staticfsp_err_tospi_b_wait_operation(uint32_ttimeout){fsp_err_t err = FSP_SUCCESS;spi_flash_status_tstatus = {RESET_VALUE}; status.write_in_progress =true;while(status.write_in_progress) {/* Get device status */ R_OSPI_B_StatusGet(&g_qspi0_flash_ctrl, &status);if(RESET_VALUE == timeout) {printf("OSPI time out occurred\r\n"); } R_BSP_SoftwareDelay(1, OSPI_B_TIME_UNIT); timeout --; }returnerr;}staticfsp_err_tospi_b_erase_operation(uint8_t*constp_address){fsp_err_t err = FSP_SUCCESS;uint32_t sector_size = RESET_VALUE;uint32_t erase_timeout = RESET_VALUE;/* Check sector size according to input address pointer, described in S28HS512T data sheet */if(OSPI_B_SECTOR_4K_END_ADDRESS < (uint32_t)p_address) { sector_size = OSPI_B_SECTOR_SIZE_256K; erase_timeout = OSPI_B_TIME_ERASE_256K; }else { sector_size = OSPI_B_SECTOR_SIZE_4K; erase_timeout = OSPI_B_TIME_ERASE_4K; }/* Performs erase sector */ err = R_OSPI_B_Erase(&g_qspi0_flash_ctrl, p_address, sector_size);/* Wait till operation completes */ err = ospi_b_wait_operation(erase_timeout);return err;}staticfsp_err_tospi_b_write_operation(uint8_t * const p_address,uint8_t *pdata, uint16_t len){fsp_err_t err = FSP_SUCCESS;/* Erase sector before write data to flash device */ err = ospi_b_erase_operation(p_address);/* Write data to flash device */ err = R_OSPI_B_Write(&g_qspi0_flash_ctrl, pdata, p_address, len);/* Wait until write operation completes */ err = ospi_b_wait_operation(OSPI_B_TIME_WRITE);return err;}staticfsp_err_tospi_b_read_operation(uint8_t * const p_address,uint8_t *pdata, uint16_t len){fsp_err_t err = FSP_SUCCESS;/* Clean read buffer */memset(pdata, RESET_VALUE, len);/* Read data from flash device */memcpy(pdata, p_address, len);return err;
}
在main中我们需要先初始化:
左右滑动查看完整内容
voidqspi_FlashInit(void){
/* Open the OSPI instance. */ fsp_err_terr=R_OSPI_B_Open(&g_qspi0_flash_ctrl, &g_qspi0_flash_cfg); assert(FSP_SUCCESS == err); /* Switch OSPI module to 1S-1S-1S mode to configure flash device */ err = R_OSPI_B_SpiProtocolSet(&g_qspi0_flash_ctrl, SPI_FLASH_PROTOCOL_EXTENDED_SPI); assert(FSP_SUCCESS == err); /* Reset flash device by driving OM_RESET pin */ R_XSPI->LIOCTL_b.RSTCS0 =0; R_BSP_SoftwareDelay(OSPI_B_TIME_RESET_PULSE, OSPI_B_TIME_UNIT); R_XSPI->LIOCTL_b.RSTCS1 =1; R_BSP_SoftwareDelay(OSPI_B_TIME_RESET_SETUP, OSPI_B_TIME_UNIT); ospi_b_write_enable();
}
然后直接初始化阶段测试QSPI,我们写入一页数据,但是之读取其中的16个,并通过串口打印:
左右滑动查看完整内容
fsp_err_tospi_b_Testoperation(uint8_t*p_address){
fsp_err_t err =FSP_SUCCESS; uint16_t i=0; err=ospi_b_erase_operation(p_address); err=ospi_b_write_operation (p_address,g_write_data,OSPI_B_APP_DATA_SIZE); if(err==FSP_SUCCESS) { /* Print execution time */ printf("Write %d bytes completed successfully\r\n", (int)(OSPI_B_APP_DATA_SIZE)); } else { printf("Write operation failure\r\n"); } printf("Write Data:\r\n"); for(i=0;i<=OSPI_B_APP_DATA_SIZE-1;i++) { printf("%d ",g_write_data[i]); } err = ospi_b_read_operation (p_address,g_read_data,16); if(err==FSP_SUCCESS) { /* Print execution time */ printf("\r\nRead %d bytes completed successfully\r\n", (int)(OSPI_B_APP_DATA_SIZE)); } else { printf("\r\nRead operation failure\r\n"); } printf("Read Data:\r\n"); for(i=0;i<=sizeof(g_read_data)-1;i++) { printf("%d ",g_read_data[i]); } /* Compare data read and date written */ if(RESET_VALUE == memcmp(&g_read_data, &g_write_data, (size_t)16)) { printf("\r\nData read matched data written\r\n"); printf("flash读写数据成功\r\n"); } else { printf("\r\nData read does not match data written\r\n"); printf("flash读写数据失败\r\n"); } /* Performs OSPI erase operation */ err = ospi_b_erase_operation(p_address); if(err==FSP_SUCCESS) { /* Print execution time */ printf("Erase sector completed successfully\r\n"); } else { printf("erase operation failure\r\n"); } return err;
}
串口打印结果如下:

从QSPI的六引脚配置、OSPI功能模块添加,到命令集定义、Flash读写擦除的代码实现,再到串口打印验证数据匹配。我们不仅掌握了不同通信协议的配置逻辑,还摸清了它们在存储外设交互中的核心应用——这次通过QSPI实现Flash的读写擦除与数据验证,正是高速通信在存储场景的典型落地。
I2C/SPI通信与显示驱动专题的技能专题还在持续拓展!如果你在实操中对QSPI的协议时序、Flash命令配置有新的感悟,或是想分享更多通信驱动的实战场景,欢迎在评论区交流。




