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edfed 16 Nov 2007, 17:59
fine
i don't understand why we need to be in 2007 to have access to good resources |
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16 Nov 2007, 17:59 |
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rhyno_dagreat 16 Nov 2007, 18:28
Lol, the code is only 6 months old tops. I took a break after I couldn't get it working (in other words, readable by Windows). Then today I realized that the jump wasn't automatically 3 bytes big, but rather a near jump, so I included the "nop" and got it working. =D
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16 Nov 2007, 18:28 |
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rhyno_dagreat 16 Nov 2007, 18:32
Oh, don't try running it. Rather, use RawWrite or the program of your choice to copy it to a floppy and open it in Windows or DOS (or another OS that supports FAT12).
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16 Nov 2007, 18:32 |
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edfed 16 Nov 2007, 19:20
is the fat 12 free? or a copyrighted owned by ms file system?
with royalties |
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16 Nov 2007, 19:20 |
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rhyno_dagreat 17 Nov 2007, 02:08
Owned by MS with Royalties. For every unit sold you have to pay them 25 cents.
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17 Nov 2007, 02:08 |
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edfed 17 Nov 2007, 12:27
ok
so, i will use fat12 for the begining of the devellopment after i will use an alternate fs for all. a fs without any royalties for anybody a GPL like licensed file system or i will not sold the os then they cannot force me to pay these shitty 25 cents/license FUCK OFF! |
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17 Nov 2007, 12:27 |
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Dex4u 17 Nov 2007, 13:31
rhyno_dagreat wrote: Owned by MS with Royalties. For every unit sold you have to pay them 25 cents. Fat12 is out of copyright, same as fat16, but its the LFN that is still under copyright. So you are free to use fat12/16 without LFN. Quote from the wiki Quote:
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17 Nov 2007, 13:31 |
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bogdanontanu 17 Nov 2007, 14:11
AFAIK everybody that ever released any FAT12/16/32 commercial device (with or without LFN) did payed the 0.25 to Microsoft.
If you want commercial success it does not make a good start to deny the copyright rights of others... maybe you will be stolen also when you have something "good to sell". But IF you do not want success then I guess Microsoft will not come after you... (although legally they can even if you gain no money) Just do not live in illusions. Hence I do suggest that you do not base your OS on FAT or be prepared to pay your respects. In fact IF you are prepared to pay then I see no reasome why you should not used FAT filesystem. Otherwise, you can use FAT as a compatibility or fair use to exchange documents... but IF your OS boots from FAT or it is based in operation on FAT (reads ini or registry or loads drives at startup etc) then you have a problem IMHO. Do not forget that Microsoft did invented this FATxx filesystem format not you. Hence "out of copyright" is kind of impossible. Patents is something else but the laws and regulations depend on each country on patents issues. |
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17 Nov 2007, 14:11 |
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Dex4u 17 Nov 2007, 16:34
bogdanontanu wrote: AFAIK everybody that ever released any FAT12/16/32 commercial device (with or without LFN) did payed the 0.25 to Microsoft. What a load of rubbish, if its does not use LFN then you do not need to pay, what "commercial device" have you see released, that does not use LFN in the last 5 year's ?. As they all use LFN, that why they need to pay. I beleave in paying your jew, but when the patent runs out, that's it. If not the world owe the UK alot of money, eg: Quote:
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17 Nov 2007, 16:34 |
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bogdanontanu 17 Nov 2007, 17:16
Quote:
Well, that is simply my own opinion... I do not intend to convince anybody and I do not even claim it to be true. Everybody can use his own mind. Devices are under NDA. |
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17 Nov 2007, 17:16 |
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bitRAKE 17 Nov 2007, 19:16
FAT, smat - any person could devise a better file system than FAT.
If your building an OS then what do you care about existing tools that use FAT? Just document whatever scheme you are using and it's limitations. Make the disk one big flat file that gets completely loaded into memory - some Atari/Amiga games did just that (there was no file system). Track which sectors get 'dirty' and write them back on shutdown. 
Where has the creativity in the world gone? |
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17 Nov 2007, 19:16 |
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edfed 19 Nov 2007, 14:21
not simply a flat file
providing the variable-size, multi-file structure, you permit sharing and easy evolutivity of all the system. the best is to make a file system that appears in HD exacttly as it must be in RAM and seek into RAM the file we need, if not in RAM, seek on Drive. Drive is then LBA mapped, LBA limit is the segment limit Pages are then clusters of the drive Clusters are pages on RAM Page translation relocate the cluster on an allocated memory segment is partition really important for exemple, i never use partition, i always use integral drives, C: on IDE1 as master contain primary system & data bios 81h on IDE1 as slave contain my system & data D: on IDE2 as master contain data E: on IDE2 as slave DVD ROM if i need a safe disk space on my system drive, i will "simply" make some hidden roots that are impossible to modify and relocate.using the IOpl rings... physically located close to the center of the plates.less frequentlly accessed, slower data transfert, secure place ( heads scratchs ) this kind of design doesn't have any signification for Flash (ROM & Drives) |
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19 Nov 2007, 14:21 |
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bitshifter 07 Dec 2007, 07:20
Has anyone written a NON-FAT bootloader?
If so, then i would like to see it! |
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07 Dec 2007, 07:20 |
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edfed 07 Dec 2007, 07:25
wait please, my brain is planing on a very strange file system s.ince two years.
also, i've made a chaining .com loader. the .com file is 64kb maximum. .com can therefore handle wich file system you want ( can ). |
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07 Dec 2007, 07:25 |
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bogdanontanu 07 Dec 2007, 07:48
Quote:
Yes, of course. For example Solar OS does not boot from a fat partition, instead it uses a proprietary format for booting from floppy or for booting from HDD / CD-ROM. I think that XP does boot from a NTFS partition  (non fat again). AFAIK Linux can boot from a non fat partition also.
Quote:
Unfortunately Solar OS is no longer open source. However to do such an "non fat" boot loader is very simple ... anybody should be able to do this by himself. Many sources are available on internet for such issues / boot loaders. |
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07 Dec 2007, 07:48 |
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Dex4u 08 Dec 2007, 00:04
Sure v2_os user its own file sys
v2_os boot loader Code: ; 1. Setup stack and datasegment ; 2. Check for a 32 bit CPU ; 3. Get info from the booted drive ; 4. Check on which CHS the bootsector is ; 5. Load all System sectors ; 6. Set the correct values ; 7. jump to System ; changed by LTH, EKS, VP ; CHS positions and disk numbers are usually stored in cx and dx: ; ch = cylinder ; cl = sector and high cylinder ; dh = head ; dl = disk ;07/07/2000: bl=Boot Partition number [ML] bits 16 org 7C00h jmp Begin FILLBYTES align 8, db 255 SIGNATURE db '+V2_FS+', 0 ; 8 FS_VERSION db '001.001', 0 ; 16 MAXOBJECTS dd 128 ; 24 CUROBJECTS dd 0 ; 28 MAXSECTORS dd 000000B40H ; 32 0b40h-for fd, was a 011223344H FIRST_AVAILABLE dd 16 ; 36 SECTORS4SYSTEM16 db 0 ; 40 SECTORS4SYSTEM32 db 0 ; 41 FIRSTDATASECTOR dd 0 ; 42 V2OS db 13, 10, 'V2-OS', 0 LOADOK db 'Ok', 13, 10, 0 WrongCPUMsg db '32 bit processor required.', 0 BadPartTableMsg db 13, 10, 'Could not find the boot partition', 0 ErrorMsg db 13, 10 db 13, 10, 'di=', 0 db 13, 10, 'si=', 0 db 13, 10, 'bp=', 0 db 13, 10, 'sp=', 0 db 13, 10, 'bx=', 0 db 13, 10, 'dx=', 0 db 13, 10, 'cx=', 0 db 13, 10, 'ax=', 0 HexDigits db '0123456789ABCDEF' MAXSECTOR db 0 MAXHEAD db 0 ;---------------------------------------------------------------------------- ; In: cx, dh = CHS ; Out: cx, dh = new CHS ; Corrupted: al IncreaseCHS: mov al, cl ; DL contains the high cylinder and cl, 00111111b ; Kill the high cylinder stuff and al, 11000000b ; Kill the sector stuff inc cl ; Increase the sector cmp cl, [MAXSECTOR] ; Check Sector jna SectorStillOK mov cl, 1 ; Sector=1, increase head (sectors start at 1, not at zero!) inc dh cmp dh, [MAXHEAD] jna HeadStillOK mov dh, 0 ; Head=0, increase cylinder (heads start at 0) inc ch jno NoCylinderOverflow add al, 01000000b ; increase high cylinder NoCylinderOverflow: HeadStillOK: SectorStillOK: or cl, al ; Merge the high-cylinder and the sector ret ;---------------------------------------------------------------------------- ; In: es:di = Buffer ; si = Nr of sectors to read ; cx,dx = CHS and disk of the first sector ; Out: es:di = end of the data in the buffer ; cx,dx = CHS and disk of the next sector ; Corrupted: ax, bx, si, bp ReadSectors: mov bp, 10 jmp short ReadLoop RetryRead: dec bp jz Error mov ah, 0 ; Reset drive int 13h jc Error ReadLoop: mov bx, di mov ax, 0201h ; Read sectors int 13h jc RetryRead mov ax, 0e2eh ; Print a dot xor bx, bx int 10h call IncreaseCHS add di, 512 ; Get next sector dec si jnz ReadLoop ret ;---------------------------------------------------------------------------- ; In: cl = byte to display ; Corrupted: ax, bx, di, bp WriteHexByte: mov ah, 0eh ; Teletype output xor bx, bx ; Page 0, color 0 shld di, cx, 12 ; load high nibble into di and di, 15 mov al, [HexDigits + di] ; al = hex digit corresponding to di int 10h ; write it mov di, cx ; same procedure with the low nibble and di, 15 mov al, [HexDigits + di] int 10h ret ;---------------------------------------------------------------------------- ; In: ds:si = Zero terminated message ; Out: ds:si = next message (if starting after the displayed message) ; Corrupted: ax, bx, bp WriteMsg: mov ah, 0Eh ; Teletype output xor bx, bx ; Page 0, color 0 jmp short StartLoop NextLetter: int 10h ; 2nd, print it StartLoop: lodsb ; 1st, load next letter or al, al jnz NextLetter ret ;---------------------------------------------------------------------------- ; In: ah = error code Error: pusha mov si, ErrorMsg mov dl, 8 .loop call WriteMsg pop cx xchg cl, ch call WriteHexByte xchg cl, ch call WriteHexByte dec dl jnz .loop jmp short $ ;---------------------------------------------------------------------------- ; In: dl = bootdisk ; Out: Begin: cli ; Dont interrupt this xor ax,ax mov ds,ax ; Set the data segment to 0, (we use an offset of 7C00h) mov ss,ax ; StackSegment is zero too mov sp, 7C00h ; Stack grows downwards ; A small CPU check to determine if we run on a 386 ; see http://www.ddj.com/articles/1996/9611/9611n/9611n.htm for details push sp pop ax cmp ax, sp je AtLeast286 WrongCPU: mov si, WrongCPUMsg call WriteMsg jmp short $ AtLeast286: mov word [18h], WrongCPU ; install an exception handler mov [1ah], cs cwde ; and try out a 32 bit instruction push dx ; Save bootdisk mov ah,8 ; and get some information about it int 13h jc Error and cl, 00111111b ; we don't check cylinders mov [MAXSECTOR], cl mov [MAXHEAD], dh mov ah,0 ; Reset the bootdrive pop dx int 13h jc Error mov si, V2OS call WriteMsg mov ax, 60h ; The segment is used as disk buffer mov es, ax ; We don't know where System is at this point, so we have to find it out. ; If we have booted from floppy, it will be at 0:0:2 (chs) right after the ; bootsector. If we booted from HD, we must get the CHS from the partition ; table, In order to get the partition of which we have booted, we must look ; for an active V2OS-parition (ID=33h). ; BTW: the partition ID 33h is reserved. It's very likely that one of ; future FAT file systems will use it. mov cx, 1 ; cx and dx point to the first sector mov dh, 0 ; on the boot disk or dl, dl jns LoadSystem ; Since floppies are not partitioned, ; we can directly read System if we ; boot from a floppy. ; Booted from HD ; We need to load the partitiontable by loading the MBR into memory xor di, di ; The MBR will be overwritten later mov si, cx call ReadSectors mov si, 512-2-64 ; Point to the partitiontable mov cx, 4 FindBootPartition: test byte [es:si], 80h ; Check if this partition is active jz FindNext cmp byte [es:si + 4], 33h ; Check if it got the correct ID je FoundThePartition FindNext: add si,16 ; Point to the next partition entry loop FindBootPartition mov si, BadPartTableMsg call WriteMsg jmp short $ FoundThePartition mov bx,5 ;[ML] sub bl, cl ; partition number mov cx, [es:si + 2] ; Get CHS from the partition table mov dh, [es:si + 1] LoadSystem: ; cx and dx are set properly. Save this info before loading System push bx ;[ML] push cx ; Save sector, head, cylinder and disk push dx ; of the bootsector call IncreaseCHS ; skip the bootsector xor di, di ; Load System at 0600h (es is still 60h) movzx si, [SECTORS4SYSTEM16] call ReadSectors mov si, LOADOK call WriteMsg ; This info is needed before jumping to System. pop dx ; Retrieve stack-saved cylinder, head, sector pop cx ; and disk pop bx ; and partition[ML] ; System prefers cl=cylinder and ch=sector, switch them before entering System ; xchg cl,ch jmp 0050h:0100h ; Pad this bootsector out to 512 bytes. Generates a compiler error if the bootsector >512b ;LTH - if ya want to see the size of the code then comment out ;the next line (the times line) times 512-2-($-$$) db 90h dw 0AA55h ; Write boot signature Note: Not coded with fasm |
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08 Dec 2007, 00:04 |
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rhyno_dagreat 08 Dec 2007, 18:42
Here's an update on the code, which hard-codes a file called "HLOWRLD.TXT" in. The only problem I find is I know that the starting cluster for the file is put inside the root directory entry, but I can't understand the formatting of the FAT entries. Are they supposed to be 12-bits each? And if so, how are they set up?
Hope what I have here at least helps you! Code: ;MINIMAL FAT12 BOOTABLE DISK! ;By: Rhyno_DaGreat (Ryan Lloyd) ;Description: A tutorial on how to hardcode a FAT12 Header for a bootdisk. ORG 7C00h ;Add offsets of the segments to this automatically - This offset will render the disk bootable. jmp start ;First two bytes - jump to start nop ;Null byte - Needed to make 3 bytes at the beginning total db "RhYn0v01" ;OEM Name dw 512 ;Bytes Per Sector db 1 ;Sectors Per Cluster dw 1 ;Reserved Sector Count - 1 For BootSector db 2 ;Number of File Allocation Tables dw 160 ;Max number of Root Entries (16 * 10) dw 80 * 2 * 18 ;Total Sectors db 0xF0 ;Media Descriptor dw 10 ;Sectors Per FAT dw 18 ;Sectors Per Track dw 2 ;Number of Heads dd 0 ;Number of Hidden Sectors start: ;Start it up! times 510-($-$$) db 0 ;Fill in rest of bootsector with zeros dw 0xAA55 ;Except last WORD, which is the boot signature |
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08 Dec 2007, 18:42 |
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Hayden 08 Dec 2007, 23:02
footnote.
We are allowed to create drivers, utils etc... for FAT sile systems. That is stuff like an optimized driver, a FAT file recovery program or some other utility. But we are not allowed to use the MS FAT technology for our own operateing systems, bootdisks etc... unless we have written permission, that usualy means an agreement must be met between you and MS. here is the FAT specs...
_________________ New User.. Hayden McKay. |
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08 Dec 2007, 23:02 |
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bitRAKE 09 Dec 2007, 00:21
Seems like a good reason to develop a x86-centric file system - something that reduces to very few instructions: XLATB and a byte-FAT array every 256 sectors. Zero bytes chain forward to next byte-FAT. Probably a bad idea with drive caches and all.
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09 Dec 2007, 00:21 |
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