_EXT_BIOS_PB Struct Reference

#include <filesystem.h>

Data Fields
uint16_t	bytespersector
	512,1024,2048,4096 - Usually 512
uint8_t	sectorspercluster
	1,2,4,8,16,32,64,128
uint16_t	reservedsectors
	FAT12/16 - Usually 1, FAT32 - Usually 32.
uint8_t	numberoffats
	Usually 2.
uint16_t	rootentrycount
	FAT32 always 0, FAT16 usually 512.
uint16_t	totalsectors16
	Total Sectors on the drive or 0 if TotalSectors32 used.
uint8_t	mediaid
	F8 for Fixed media, F0 usually for Removable media.
uint16_t	sectorsperfat16
	FAT32 always 0, Number of Sectors per FAT.
uint16_t	sectorspertrack
	Sectors Per Track for Int13.
uint16_t	numberofheads
	Number of Header for Int13 eg 1.44MB = 2.
uint32_t	hiddensectors
	Number of Hidden Sectors preceeding Partition.
uint32_t	totalsectors32
	Total Sectors on the drive or 0 if TotalSectors16 used.
uint32_t	sectorsperfat32
	Number of Sectors per FAT.
uint16_t	extendedflags
	Bits 0-3 – Zero-based number of active FAT. Only valid if mirroring.
uint16_t	filesysversion
	FAT32 Version (Current 0:0).
uint32_t	rootcluster
	Usually Cluster 2.
uint16_t	filesysinfosector
	Usually 1.
uint16_t	backupbootsector
	Usually 6.
uint8_t	reserved [12]
	Always 0.

Detailed Description

FAT32 BIOS Parameter Block

Field Documentation

bytespersector

uint16_t bytespersector

512,1024,2048,4096 - Usually 512

sectorspercluster

uint8_t sectorspercluster

1,2,4,8,16,32,64,128

reservedsectors

uint16_t reservedsectors

FAT12/16 - Usually 1, FAT32 - Usually 32.

numberoffats

uint8_t numberoffats

Usually 2.

rootentrycount

uint16_t rootentrycount

FAT32 always 0, FAT16 usually 512.

totalsectors16

uint16_t totalsectors16

Total Sectors on the drive or 0 if TotalSectors32 used.

mediaid

uint8_t mediaid

F8 for Fixed media, F0 usually for Removable media.

sectorsperfat16

uint16_t sectorsperfat16

FAT32 always 0, Number of Sectors per FAT.

sectorspertrack

uint16_t sectorspertrack

Sectors Per Track for Int13.

numberofheads

uint16_t numberofheads

Number of Header for Int13 eg 1.44MB = 2.

hiddensectors

uint32_t hiddensectors

Number of Hidden Sectors preceeding Partition.

totalsectors32

uint32_t totalsectors32

Total Sectors on the drive or 0 if TotalSectors16 used.

sectorsperfat32

uint32_t sectorsperfat32

Number of Sectors per FAT.

extendedflags

uint16_t extendedflags

Bits 0-3 – Zero-based number of active FAT. Only valid if mirroring.

filesysversion

uint16_t filesysversion

FAT32 Version (Current 0:0).

rootcluster

uint32_t rootcluster

Usually Cluster 2.

filesysinfosector

uint16_t filesysinfosector

Usually 1.

backupbootsector

uint16_t backupbootsector

Usually 6.

reserved

uint8_t reserved[12]

Always 0.

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The documentation for this struct was generated from the following file:

• ultibo/filesystem.h