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Fix problem with FAT12

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git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@711 6ac86273-5f31-0410-b378-82cca8765d1b
This commit is contained in:
Bart Oldeman 2003-10-03 13:50:38 +00:00
parent 20299d3642
commit 5f6d47797e
1 changed files with 3 additions and 3 deletions
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6
boot/boot.asm
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@ -308,7 +308,8 @@ fat_12: add si, si ; multiply cluster number by 3...
; the number was odd, CF was set in the last shift instruction. ; the number was odd, CF was set in the last shift instruction.
jnc fat_even jnc fat_even
div word[LBA_PACKET]; luckily 16 !! -- divide the cluster number mov cl, 4
shr ax, cl
fat_even: and ah, 0x0f ; mask off the highest 4 bits fat_even: and ah, 0x0f ; mask off the highest 4 bits
cmp ax, 0x0ff8 ; check for EOF cmp ax, 0x0ff8 ; check for EOF
@ -449,7 +450,7 @@ read_next:
read_normal_BIOS: read_normal_BIOS:
;******************** END OF LBA_READ ************************ ;******************** END OF LBA_READ ************************
mov ax,LBA_SECTOR_0 mov cx,LBA_SECTOR_0
mov dx,LBA_SECTOR_16 mov dx,LBA_SECTOR_16
@ -462,7 +463,6 @@ read_normal_BIOS:
; + head * sectPerTrack offset in cylinder ; + head * sectPerTrack offset in cylinder
; + track * sectPerTrack * nHeads offset in platter ; + track * sectPerTrack * nHeads offset in platter
; ;
xchg ax, cx
mov al, [sectPerTrack] mov al, [sectPerTrack]
mul byte [nHeads] mul byte [nHeads]
xchg ax, cx xchg ax, cx