帮我写一段stm32l431 sd卡写入的驱动

好的，以下是一段基本的stm32l431 sd卡写入的驱动代码：

#include "stm32l4xx_hal.h"
#include "fatfs.h"

#define SD_CS_GPIO_Port GPIOB
#define SD_CS_Pin GPIO_PIN_12

static FATFS fs;
static FIL file;

void SD_Write(char* filename, char* data)
{
FRESULT res;
UINT bytesWritten;

// Mount SD card
res = f_mount(&fs, "", 1);
if (res != FR_OK)
{
// Error handling
return;
}

// Open file for writing
res = f_open(&file, filename, FA_CREATE_ALWAYS | FA_WRITE);
if (res != FR_OK)
{
// Error handling
f_mount(NULL, "", );
return;
}

// Write data to file
res = f_write(&file, data, strlen(data), &bytesWritten);
if (res != FR_OK)
{
// Error handling
f_close(&file);
f_mount(NULL, "", );
return;
}

// Close file and unmount SD card
f_close(&file);
f_mount(NULL, "", );
}

注意：以上代码仅供参考，具体实现需要根据具体的硬件和软件环境进行调整。