- /*-----------------------------------------------------------------------*/
- 02
- /* Load a sector and check if it is an FAT Volume Boot Record */
- 03
- /*-----------------------------------------------------------------------*/
- 04
-
- 05
- static
- 06
- BYTE check_fs ( /* 0:FAT-VBR, 1:Valid BR but not FAT, 2:Not a BR, 3:Disk error */
- 07
- FATFS *fs, /* File system object */
- 08
- DWORD sect /* Sector# (lba) to check if it is an FAT boot record or not */
- 09
- )
- 10
- {
- 11
- if (disk_read(fs->drv, fs->win, sect, 1) != RES_OK) /* Load boot record */
- 12
- return 3;
- 13
- if (LD_WORD(&fs->win[BS_55AA]) != 0xAA55) /* Check record signature (always placed at offset 510 even if the sector size is >512) */
- 14
- return 2;
- 15
-
- 16
- if ((LD_DWORD(&fs->win[BS_FilSysType]) & 0xFFFFFF) == 0x544146) /* Check "FAT" string */
- 17
- return 0;
- 18
- if ((LD_DWORD(&fs->win[BS_FilSysType32]) & 0xFFFFFF) == 0x544146)
- 19
- return 0;
- 20
-
- 21
- return 1;
- 22
- }
就return 2了；最终返回是FR_NO_FILESYSTEM，没有有效的FAT卷？
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楼主
