SD Card Logging

LOS SD Driver: calls the FatFS middleware. This implements the generic storage device interface.
LOS SD Driver SPI Implementation: this layer implements the SPI communication required for the FatFS middleware to communicate with the SD card
- Implementation: How to Interface SD card using SPI in STM32

Example usage of the LOS SD Driver (... indicates other parts of the code in a stm32 project)

#include "LOS_D_sd.hpp"

...

int main(void)
{
  ...
  /* USER CODE BEGIN 2 */
  uint8_t res;

  SDCard sd;
  StorageDevice* storage_device = &sd;
  
  const char* file_name = "test.txt";
  const char* write_data = "test\ntest";
  size_t write_data_size = strlen(write_data);
  char read_data[100];
  size_t file_size;
  
  /* Check if test file 1 exists */
  bool file_exist = storage_device->checkExist(file_name);
  if (file_exist) {
    myprintf("File exists!\r\n");
  } else {
    myprintf("File does not exist!\r\n");
  }
  
  /* Write to file (will create the file first if it does not exist) */
  res = storage_device->write(file_name, write_data, write_data_size);
  if (res != 0) {
    myprintf("Failed to write to file! Error code = %d\r\n", res);
  }
  
  /* Get file size */
  file_size = storage_device->length(file_name);
  myprintf("File size: %d\r\n", file_size);
  
  /* Read from file */
  memset(read_data, 0, 100);
  res = storage_device->read(file_name, read_data, file_size);
  if (res == 0) {
    myprintf("Read file content:\r\n%s\r\n", (char*)readData);
  } else {
    myprintf("Failed to read from file! Error code = %d\r\n", res);
  }
  
  /* Perform I/O operation on another file */
  const char* file_name_2 = "test2.txt";
  res = storage_device->write(file_name_2, write_data, write_data_size);
  if (res != 0) {
		myprintf("Failed to write to another file! Error code = %d\r\n", res);
  }

  /* Clean up SD card */
  res = storage_device->cleanup();
  if (res != 0) {
    myprintf("Failed to clean up SD card! Error code = %d\r\n", res);
  }
  /* USER CODE END 2 */
  ...
}

...