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Prusa MINI Firmware overview
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Boot sector for a FAT32 volume. More...
#include <SdFatStructs.h>
Public Attributes | |
| uint8_t | jump [3] |
| char | oemId [8] |
| uint16_t | bytesPerSector |
| uint8_t | sectorsPerCluster |
| uint16_t | reservedSectorCount |
| uint8_t | fatCount |
| uint16_t | rootDirEntryCount |
| uint16_t | totalSectors16 |
| uint8_t | mediaType |
| uint16_t | sectorsPerFat16 |
| uint16_t | sectorsPerTrack |
| uint16_t | headCount |
| uint32_t | hidddenSectors |
| uint32_t | totalSectors32 |
| uint32_t | sectorsPerFat32 |
| uint16_t | fat32Flags |
| uint16_t | fat32Version |
| uint32_t | fat32RootCluster |
| uint16_t | fat32FSInfo |
| uint16_t | fat32BackBootBlock |
| uint8_t | fat32Reserved [12] |
| uint8_t | driveNumber |
| uint8_t | reserved1 |
| uint8_t | bootSignature |
| uint32_t | volumeSerialNumber |
| char | volumeLabel [11] |
| char | fileSystemType [8] |
| uint8_t | bootCode [420] |
| uint8_t | bootSectorSig0 |
| uint8_t | bootSectorSig1 |
Boot sector for a FAT32 volume.
| uint8_t fat32_boot::jump[3] |
The first three bytes of the boot sector must be valid, executable x 86-based CPU instructions. This includes a jump instruction that skips the next nonexecutable bytes.
| char fat32_boot::oemId[8] |
This is typically a string of characters that identifies the operating system that formatted the volume.
| uint16_t fat32_boot::bytesPerSector |
The size of a hardware sector. Valid decimal values for this field are 512, 1024, 2048, and 4096. For most disks used in the United States, the value of this field is 512.
| uint8_t fat32_boot::sectorsPerCluster |
Number of sectors per allocation unit. This value must be a power of 2 that is greater than 0. The legal values are 1, 2, 4, 8, 16, 32, 64, and 128. 128 should be avoided.
| uint16_t fat32_boot::reservedSectorCount |
The number of sectors preceding the start of the first FAT, including the boot sector. Must not be zero
| uint8_t fat32_boot::fatCount |
The number of copies of the FAT on the volume. The value of this field is always 2.
| uint16_t fat32_boot::rootDirEntryCount |
FAT12/FAT16 only. For FAT32 volumes, this field must be set to 0.
| uint16_t fat32_boot::totalSectors16 |
For FAT32 volumes, this field must be 0.
| uint8_t fat32_boot::mediaType |
This dates back to the old MS-DOS 1.x media determination and is no longer usually used for anything. 0xF8 is the standard value for fixed (nonremovable) media. For removable media, 0xF0 is frequently used. Legal values are 0xF0 or 0xF8-0xFF.
| uint16_t fat32_boot::sectorsPerFat16 |
On FAT32 volumes this field must be 0, and sectorsPerFat32 contains the FAT size count.
| uint16_t fat32_boot::sectorsPerTrack |
| uint16_t fat32_boot::headCount |
| uint32_t fat32_boot::hidddenSectors |
Count of hidden sectors preceding the partition that contains this FAT volume. This field is generally only relevant for media visible on interrupt 0x13.
| uint32_t fat32_boot::totalSectors32 |
Contains the total number of sectors in the FAT32 volume.
| uint32_t fat32_boot::sectorsPerFat32 |
Count of sectors occupied by one FAT on FAT32 volumes.
| uint16_t fat32_boot::fat32Flags |
This field is only defined for FAT32 media and does not exist on FAT12 and FAT16 media. Bits 0-3 – Zero-based number of active FAT. Only valid if mirroring is disabled. Bits 4-6 – Reserved. Bit 7 – 0 means the FAT is mirrored at runtime into all FATs. – 1 means only one FAT is active; it is the one referenced in bits 0-3. Bits 8-15 – Reserved.
| uint16_t fat32_boot::fat32Version |
FAT32 version. High byte is major revision number. Low byte is minor revision number. Only 0.0 define.
| uint32_t fat32_boot::fat32RootCluster |
Cluster number of the first cluster of the root directory for FAT32. This usually 2 but not required to be 2.
| uint16_t fat32_boot::fat32FSInfo |
Sector number of FSINFO structure in the reserved area of the FAT32 volume. Usually 1.
| uint16_t fat32_boot::fat32BackBootBlock |
If nonzero, indicates the sector number in the reserved area of the volume of a copy of the boot record. Usually 6. No value other than 6 is recommended.
| uint8_t fat32_boot::fat32Reserved[12] |
Reserved for future expansion. Code that formats FAT32 volumes should always set all of the bytes of this field to 0.
| uint8_t fat32_boot::driveNumber |
Related to the BIOS physical drive number. Floppy drives are identified as 0x00 and physical hard disks are identified as 0x80, regardless of the number of physical disk drives. Typically, this value is set prior to issuing an INT 13h BIOS call to specify the device to access. The value is only relevant if the device is a boot device.
| uint8_t fat32_boot::reserved1 |
| uint8_t fat32_boot::bootSignature |
| uint32_t fat32_boot::volumeSerialNumber |
A random serial number created when formatting a disk, which helps to distinguish between disks. Usually generated by combining date and time.
| char fat32_boot::volumeLabel[11] |
A field once used to store the volume label. The volume label is now stored as a special file in the root directory.
| char fat32_boot::fileSystemType[8] |
A text field with a value of FAT32.
| uint8_t fat32_boot::bootCode[420] |
| uint8_t fat32_boot::bootSectorSig0 |
| uint8_t fat32_boot::bootSectorSig1 |
1.8.16 
