mbed-os storage access example.
Dependencies: SDBlockDevice_GR_PEACH USBHost_custom
This is a sample for using USB memory and SD card in mbed-os 5.4 or later version.
Import program
00001 #include "mbed.h" 00002 #include "FATFileSystem.h" 00003 #include "SDBlockDevice_GR_PEACH.h" 00004 #include "USBHostMSD.h" 00005 00006 int main() { 00007 int i = 0; 00008 int storage_type = 0; 00009 char storage_str[16]; 00010 00011 FATFileSystem fs("storage"); 00012 SDBlockDevice_GR_PEACH sd; 00013 USBHostMSD usb; 00014 00015 while(1) { 00016 // try to connect a storage device 00017 while (1) { 00018 if (sd.connect()) { 00019 storage_type = 0; // SD 00020 strcpy(storage_str, "SD card"); 00021 fs.mount(&sd); 00022 break; 00023 } 00024 if (usb.connect()) { 00025 storage_type = 1; // USB 00026 strcpy(storage_str, "USB memory"); 00027 fs.mount(&usb); 00028 break; 00029 } 00030 Thread::wait(500); 00031 } 00032 00033 // in a loop, append a file 00034 // if the device is disconnected, we try to connect it again 00035 while(1) { 00036 // append a file 00037 FILE * fp = fopen("/storage/test1.txt", "a"); 00038 00039 if (fp != NULL) { 00040 fprintf(fp, "Hello %s World: %d!\r\n", storage_str, i++); 00041 printf("Goodbye World!\r\n"); 00042 fclose(fp); 00043 } else { 00044 printf("FILE == NULL\r\n"); 00045 } 00046 Thread::wait(500); 00047 00048 // if device disconnected, try to connect again 00049 if (storage_type == 0) { 00050 if (!sd.connected()) break; 00051 } else { 00052 if (!usb.connected()) break; 00053 } 00054 } 00055 fs.unmount(); 00056 } 00057 }