f_lseek); //Continue to write the previous data that will not erase                                                                                                                                                           

. Open the CubeMX new file, select the microcontroller chip

2. Set the system frequency: See the figure below

3. Set SPI3, select the settings as host mode, and the others are fine.

4. Select FATFS and check User-defined. All other default settings are fine (note that the maximum and minimum values of the partition are 512).

5. The above configuration is basically completed. Now the final configuration of the generated project is:

Complete the above settings and click "GENERATE COOD" to generate the project.

6. First set the SD card driver and add two functions to the spi.c file: (Just name the function name yourself as needed)

Note: Remember to declare the function in the spi.h file. Spi configuration and pin initialization have been completed automatically without having to configure again.

7. Create a new SD_Driver.c and SD_Driver.h file (implementing the driver for the SD card).

mainly includes:

void SD_CS(uint8_t p) //SPI3 pin control uint8_t SD_GETCID(uint8_t *cid_data) //Read CID information of the SD card uint8_t SD_GETCSD(uint8_t *cid_data) //Read CID information of the SD card uint32_t SD_GetSectorCount(void) //Read the number of sectors of the SD card uint8_t SD_init(void) //SD card initialization function uint8_t SD_ReadDisk(uint8_t*buf,uint32_t sector,uint8_t cnt) //Read data from the SD card uint8_t SD_ReceiveData(uint8_t *data, uint16_t len) //Read data of the specified length in the SD card uint8_t SD_SendBlock(uint8_t*buf,uint8_t cmd) //Write a 512-byte data to the SD card int SD_sendcmd(uint8_t cmd,uint32_t arg,uint8_t crc) //Send commands to the SD card through SPI uint8_t SD_WriteDisk(uint8_t*buf,uint32_t sector,uint8_t cnt) //Write data to the SD card 

8. Fill in the "user_diskio.c" file with the following five functions to realize the association between the file system and SD.

USER_initialize(); USER_ioctl(); USER_read(); USER_status(); USER_write();

If necessary, fill in fatfs.c with get_fattime(); function set date

DWORD get_fattime (void) { return ((2010UL-1980) 25) /* Year = 2010 */ | (11UL 21) /* Month = 11 */ | (2UL 16) /* Day = 2 */ | (15U 11) /* Hour = 15 */ | (0U 5) /* Min = 0 */ | (0U 1) /* Sec = 0 */ ; }

9. This is basically the configuration! The following is to implement the reading and writing of the SD card in the main function;

//Define some variables FATFS fs; FIL file; uint8_t res=0; UINT Br,Bw; char path[4]="0:"; uint8_t testBuffer[]="SD¿¨Ð´ëÖÐÓ¢ÎIJâÊÔ,SD card Chinese and English reading and writing test!! \r\n"; uint8_t ReadBuffer[512]; char success[]="Data writing Ok!\r\n"; char error[]="error!\r\n"; char mount[]="File system mount successfully! \r\n"; char open[]="ÎFile is open! \r\n"; int main(){ /***No more writing in various initializations***/ res=f_mount(&fs,"0:",0); //mount the file system if(res!=FR_OK){ HAL_UART_Transmit(&huaart2,(uint8_t *) &error,sizeof(error),100); }else{ HAL_UART_Transmit(&huaart2,(uint8_t *) &mount,sizeof(mount),100); } while(1) { if(f_open(&file,"hello.txt",FA_OPEN_ALWAYS|FA_WRITE)==FR_OK){ HAL_UART_Transmit(&huaart2,(uint8_t *) &open,sizeof(open),100); f_lseek(&file, f_size(&file)); //Then write the previous data that will not be erased if(f_write(&file,testBuffer,sizeof(testBuffer),&Bw)==FR_OK){ HAL_UART_Transmit(&huaart2,(uint8_t *) &success,sizeof(success),100); f_close(&file); //Be sure to close the file }}} }