Based on the FATS file system of the library function version of punctual atoms, it is possible to write strings to the file and read the file content. This refers to the txt file, and the rest of the files are actually the same, and they are read into bytes.
#include "led.h"
#include "delay.h"
#include "sys.h"
#include "usart.h"
#include "key.h"
#include "MMC_SD.h"
#include "ff.h"
#include "exfuns.h"
#include "fattester.h"
#include "malloc.h"
#include "string.h"
extern FATFS *fs[2];
extern FIL *file; //文件1
extern UINT br, bw; //读写变量
// 将字符串写入txt文件
void write_to_txt(const char *filename, const char *str) {
FRESULT res;
res = f_open(file, filename, FA_CREATE_ALWAYS | FA_WRITE); // 打开或创建文件
if (res != FR_OK) {
printf("Failed to open file: %d\r\n", res);
return;
}
res = f_write(file, str, strlen(str), &bw); // 写入数据
if (res != FR_OK) {
printf("Failed to write file: %d\r\n", res);
f_close(file);
return;
}
res = f_close(file); // 关闭文件
if (res != FR_OK) {
printf("Failed to close file: %d\r\n", res);
return;
}
printf("Write successfully, %u bytes written\r\n", bw);
}
void append_to_file(const char *filename, const char *data) {
FRESULT res;
res = f_open(file, filename, FA_WRITE | FA_OPEN_ALWAYS); // 打开文件
if (res != FR_OK) {
printf("Failed to open file: %d\r\n", res);
return;
}
res = f_lseek(file, file->fsize); // 将写入指针定位到文件末尾
if (res != FR_OK) {
printf("Failed to seek file: %d\r\n", res);
f_close(file);
return;
}
res = f_write(file, data, strlen(data), &bw); // 写入数据到文件末尾
if (res != FR_OK || bw == 0) {
printf("Failed to write file: %d\r\n", res);
f_close(file);
return;
}
res = f_close(file); // 关闭文件
if (res != FR_OK) {
printf("Failed to close file: %d\r\n", res);
return;
}
}
#define MAX_LINE_SIZE 100
// 动态读取txt文件的行并进行处理
void process_lines_from_txt(const char *filename) {
FRESULT res;
char line[MAX_LINE_SIZE];
res = f_open(file, filename, FA_READ); // 打开文件
if (res != FR_OK) {
printf("Failed to open file: %d\r\n", res);
return;
}
while (f_gets(line, MAX_LINE_SIZE, file) != NULL) {
// 按行读取文件内容
printf("%s", line); // 打印读取的内容
// 这里可以对每一行进行处理，例如调用其他函数进行处理
// 读取下一行之前可以进行必要的等待或延时操作
}
res = f_close(file); // 关闭文件
if (res != FR_OK) {
printf("Failed to close file: %d\r\n", res);
return;
}
}
int main(void) {
char str[] = "Hello, world!";
char str1[] = "\r\nHello, world!";
u32 total, free;
u8 t = 0;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);// 设置中断优先级分组2
delay_init(); //延时函数初始化
uart_init(115200); //串口初始化为9600
exfuns_init(); //为fatfs相关变量申请内存
LED_Init(); //LED初始化
mem_init(); //初始化内存池
while (SD_Initialize()) //检测SD卡
{
delay_ms(200);
LED0 = !LED0;//DS0闪烁
}
exfuns_init(); //为fatfs相关变量申请内存
f_mount(fs[0], "0:", 1); //挂载SD卡
f_mount(fs[1], "1:", 1); //挂载FLASH.
while (exf_getfree("0", &total, &free)) //得到SD卡的总容量和剩余容量
{
delay_ms(200);
LED0 = !LED0;//DS0闪烁
}
//打印大小
printf("SD卡容量:%d MB\r\nSD卡剩余容量:%d MB\r\n", total / 1024, free / 1024);
//write_to_txt("text.txt", str); // 写入字符串到txt文件
//append_to_file("text.txt", str1); // 写入字符串到txt文件
process_lines_from_txt("text.txt");
while (1) {
t++;
delay_ms(200);
LED0 = !LED0;
}
}
List of supported files:
//文件类型列表
const u8 *FILE_TYPE_TBL[6][13]=
{
{
"BIN"}, //BIN文件
{
"LRC"}, //LRC文件
{
"NES"}, //NES文件
{
"TXT","C","H"}, //文本文件
{
"MP1","MP2","MP3","MP4","M4A","3GP","3G2","OGG","ACC","WMA","WAV","MID","FLAC"},//音乐文件
{
"BMP","JPG","JPEG","GIF"},//图片文件
The following figure is the display of the read data:
