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revolution 12 Nov 2011, 15:15
I couldn't find the source code in your post. It is difficult for us to help you without knowing what you have done.
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12 Nov 2011, 15:15 |
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egos 12 Nov 2011, 16:04
Maybe boot loader was written on CD/DVD incorrectly, i.e. as for floppy emulation mode.
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12 Nov 2011, 16:04 |
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smiddy 12 Nov 2011, 17:26
@Revolution: I will post it, it is in an ugly state...here's the beginning of the snippet:
Code: ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Start Boot Procedure ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Begin: ; Begining of instructions CLI ; Turn off intterrupts MOV [CDDriveNumber],DL ; Save boot drive mov ax,7000h mov gs,ax mov bx,530h mov [gs:bx],dl ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Relocation code; move code to 0x0000:0600 (Linear 00000600) ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; XOR AX,AX ; Place ES and DS at same segment MOV SS,AX ; Set Stack below new location MOV SP,5FEh ; 0000:05FE MOV ES,AX ; ES = 0 MOV DS,AX ; DS = 0 MOV DI,600h ; DI = 600h (The new location) CLD ; Clear direction MOV CX,80h ; Place CX = 128 MOV SI,7C00h ; Offset of this code (Assume segment 0) REP MOVSD ; Copy code over with DWORDs JMP 60h:NewLowerLocation ; Jump to our new location to force CS = 60h NewLowerLocation: MOV AX,60h ; Reestablish segments (60h:0h or linear 600h MOV DS,AX ; to 105FFh) MOV ES,AX MOV FS,AX MOV GS,AX STI ; Turn interrupts back on MOV SI,WelcomeMessage ; Save pointer to welcome message CALL PrintString ; Print the welcome message MOV SI,TheEndOfTheLine CALL PrintString MOV AL,[CDDriveNumber] MOV CL,8 CALL ToHex MOV SI,DriveNumberReported CALL PrintString MOV SI,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,TheEndOfTheLine CALL PrintString MOV DL,[CDDriveNumber] ; Prepare to read CD-ROM, load boot drive MOV AH,48h ; Use function 41h MOV SI,DiskResultsBuffer ; Results buffer to load INT 13h ; Call Check Extensions Present? JC Failure Code: Failure: mov AL,AH ; Put the error into lowest bits mov cl,8 ; only 8 bits call ToHex ; Get what is in the XX to display MOV SI,FailureMessage ; reboot message CALL PrintString mov si,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,TheEndOfTheLine CALL PrintString mov SI,PressAnyKeyMessage CALL PrintString MOV AH,0 ; Reboot on error INT 16h ; BIOS GetKey INT 19h ; BIOS Reboot I am using the beginning of my original floppy boot code, minus all the boot sector stuff needed for FAT12. I am simply relocating the code (which I can bypass if needed), then jumping to the new sector, then doing a INT 13h Function 48h to get the Disk Parameters block, but the carry flag is set and the error code is 1 (invalid command). 
@egos: The iso I am creating has No Emulation identified in the Initial/Default Entry: Code:
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Initial/Default Entry
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
db 88h ; Boot indicator
db 0 ; Media type (0 = "no emulation")
dw 07C0h ; Load segment
db 0 ; Partition type (assumed to be unused for "no emulation")
db 0 ; Unused, must be 0
dw (BootLoader.End - BootLoader + 511) / 512 ; Sector count (virtual 512-byte sectors)
dd (BootLoader - CDROMImageStart) / 2048 ; First sector number for boot loader
times 20 db 0 ; Unused, must be zero
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12 Nov 2011, 17:26 |
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DJ Mauretto 12 Nov 2011, 18:42
Hello
First of all you must check the extensions present (AH 41h) then the cdrom don't never returns the drive parameters for no emulation.. Think about it, if you don't make emulation which drive parameters (Ah 48h) can i return to you 
CDrom parameters
Note that the AH 48h Get drive parameters for me work only with real HD and USB, but with cdrom boot i don't have get nothing at all in every pc where i test my cd bootloader  _________________ Nil Volentibus Arduum  |
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12 Nov 2011, 18:42 |
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egos 12 Nov 2011, 19:19
smiddy, set ds before MOV [CDDriveNumber],DL
DJ Mauretto, if ISO boot loader gets control then extensions are present (though you can check this by hand for absolute guaranties). EDD returns device parameters for CD/DVD as well. It's fundamental info for detecting boot device. |
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12 Nov 2011, 19:19 |
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DJ Mauretto 12 Nov 2011, 19:34
Quote: if ISO boot loader gets control then extensions are present
NO, you can use classic bios ah 02h to get sector from cd without assume EDD is present. BIOS ah 02h is universal and work with all drive, EDD is not always supported. Quote: EDD returns device parameters for CD/DVD as well No, in all PC that i tryed no drive parameters are present, always carry set, anyway i don't tryed all pc in the world
Quote: It's fundamental info for detecting boot device. If you make floppy emulation ah 41 check extensions is not supported at all, Then What is your boot device ? _________________ Nil Volentibus Arduum |
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12 Nov 2011, 19:34 |
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smiddy 12 Nov 2011, 20:16
@ DJ Mauretto: I had assumed that the CD-ROM parameters would be there. I have read conflicting information on Function 48 and Function 41. I will try 41h first.
@egos: Yeah, I wondered if I should disregard the move portion and leave all the segment registers as the should be from the Initial/Default Entry. I'll give these both a try. Thanks folks! I'll report back in a little while, my 4 year old if needing attention.  |
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12 Nov 2011, 20:16 |
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smiddy 12 Nov 2011, 20:21
BTW I just re-read this from El Torito:
Code: When the boot image is simply a “loader” or stand alone program, and NO EMULATION is desired, the drive numbers will be unaffected after the boot image is loaded. The specified number of sectors are loaded at the specified segment (usually 7C0), and then the BIOS jumps to the load address. The software can retrieve a pointer to its boot information by issuing INT 13, Function 4B, AL=1. I think I will try this first, since I'm trying no emulation perhaps I need to run Function 4Bh first? |
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12 Nov 2011, 20:21 |
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egos 12 Nov 2011, 21:45
DJ Mauretto wrote: NO, you can use classic bios ah 02h to get sector from cd without assume EDD is present. Quote: No, in all PC that i tryed no drive parameters are present, always carry set, anyway i don't tryed all pc in the world My PC: Code: size: 32 part: 0 type: 0 extra: 0 bus type: PCI interface type: ATAPI interface: 00 1F 02 00 00 00 00 00 device: 00 00 00 00 00 00 00 00 My Bochs: Code: size: 32 part: 0 type: 0 extra: 0 bus type: ISA interface type: ATA interface: F0 01 00 00 00 00 00 00 device: 00 00 00 00 00 00 00 00 Quote: If you make floppy emulation ah 41 check extensions is not supported at all, _________________ If you have seen bad English in my words, tell me what's wrong, please. |
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12 Nov 2011, 21:45 |
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smiddy 12 Nov 2011, 23:01
So, here are the results using INT 13h Function 4B, AL=1: I get a return packet that says the CD-ROM drive is E0h, not 00h form the DL upon boot. When I use the returned CD-ROM drive number in the DL for Functions 41h and 42h, they both work with the returned drive packet. Once I clean up the code for the start I will post it. BTW, I removed all the moveable code stuff, setup the segments as 07C0h and all is well in the world.
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12 Nov 2011, 23:01 |
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egos 12 Nov 2011, 23:58
If so DL will hold 0E0h in entry point. Function 41h doesn't return device address packet.
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12 Nov 2011, 23:58 |
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DJ Mauretto 13 Nov 2011, 08:18
Quote: Function 2 is not used for CD/DVD. "El Torito" Spec. is based on EDD Spec. You can't boot from CD/DVD without EDD. I never had any problem with Ah 02 function in every PC, but note that i don't use no emulation mode. I have never seen the data about ATAPI drive parameters that you post 
Maybe you get this data only with no emulation... Anyway good for you _________________ Nil Volentibus Arduum |
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13 Nov 2011, 08:18 |
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egos 13 Nov 2011, 10:49
If you don't use "No emulation" mode don't speak about it.
DJ Mauretto wrote: then the cdrom don't never returns the drive parameters for no emulation.. _________________ If you have seen bad English in my words, tell me what's wrong, please. |
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13 Nov 2011, 10:49 |
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DJ Mauretto 13 Nov 2011, 11:20
Quote: If you don't use "No emulation" mode don't speak about it. Hey Young boy, i am a free person, I do not have to ask permission to talk , anyway please post also the drive parameters of your CDrom, you have skipped it , post all result buffer
I did the test several years ago, and my actual boot from cd use ah 02, somehow I have chosen this path many years ago because it was compatible with all pc. NB: For me drive parameters are this: Number of physical cylinders. Number of physical heads. Number of physical sectors per track. Number of physical sectors. Number of bytes in a sector. and so on... Maybe for you the drive parameters are only Interface type = ATAPI _________________ Nil Volentibus Arduum |
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13 Nov 2011, 11:20 |
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egos 13 Nov 2011, 18:01
DJ Mauretto wrote: anyway please post also the drive parameters of your CDrom, Quote: For me drive parameters are this: Quote: Maybe for you the drive parameters are only Interface type = ATAPI _________________ If you have seen bad English in my words, tell me what's wrong, please. |
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13 Nov 2011, 18:01 |
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DJ Mauretto 13 Nov 2011, 19:47
Quote: Do you know what is CD/DVD?
Very funny Quote: And do you know what is IDENTIFY DEVICE command?
You make me laughing
The truth is that ah 48 for cd don't return drive parameters as i told you
Perhaps the problem is that we mean 2 completely different things. You want to know the device path, I mean the drive parameters as Number of physical cylinders. Number of physical heads. Number of physical sectors per track. and so on _________________ Nil Volentibus Arduum |
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13 Nov 2011, 19:47 |
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smiddy 13 Nov 2011, 20:18
You two are killing me...
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13 Nov 2011, 20:18 |
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smiddy 14 Nov 2011, 04:22
Ok, so I've gotten it to work and here's the fundamentals:
Code: ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ;; ;; Project : smiddyOS (CD-ROM Booter) ;; ;; Author : smiddy ;; ;; Website : ;; ;; Date : November 13, 2011 ;; ;; Poop : Bootloader, read CD-ROM, load kernel (CD_ROM VIEWER) ;; ;; Filename : cdboot1.asm ;; ;; Assembler Command: Using FASMW IDE ;; ;; ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ;; ;; Useage: Using CDBOOT1.BIN as the boot loader from the created ISO from the ;; ;; CD-ROM creating CDROM.ASM from from within FASMW IDE. ;; ;; ;; ;; See CDROM.ASM for further details. ;; ;; ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ;; ;; v1.00a - Alpha release; CD-ROM compatible booter; learning the CD/DVD/BD boot ;; ;; process. Fill in the blanks and get yourself moving. I am working the ;; ;; rest of the code out, now that it boots. ;; ;; ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; format binary as "bin" ; Tell FASM to make an BIN image ORG 0 BootSector: ; Label in order to determine size of code for ; padding at the end. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Start Boot Procedure ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Begin: ; Begining of instructions CLI ; Turn off intterrupts MOV [CDDriveNumber],DL ; Save boot drive mov ax,07C0h ; Boot Segment mov gs,ax mov ds,ax mov es,ax mov fs,ax STI ; Turn interrupts back on MOV SI,WelcomeMessage ; Save pointer to welcome message CALL PrintString ; Print the welcome message MOV SI,TheEndOfTheLine CALL PrintString MOV AL,[CDDriveNumber] MOV CL,8 CALL ToHex MOV SI,DriveNumberReported CALL PrintString MOV SI,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,TheEndOfTheLine CALL PrintString MOV DL,[CDDriveNumber] ; Prepare to read CD-ROM, load boot drive MOV AH,4Bh ; Use function 4Bh MOV AL,1 MOV SI,DiskResultsBuffer ; Results buffer to load INT 13h ; Call Check Extensions Present? JC Failure MOV SI,DiskResultsBufferMessage ; Loading this one CALL PrintString MOV SI,SizeOfPacketInBytes CALL PrintString MOV AL,[DiskResultsBuffer] MOV CL,8 CALL ToHex MOV SI,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,TheEndOfTheLine CALL PrintString MOV SI,BootMediaType CALL PrintString MOV AL,[DiskResultsBuffer+1] MOV CL,8 CALL ToHex MOV SI,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,TheEndOfTheLine CALL PrintString MOV SI,DriveNumberFromPacket CALL PrintString MOV AL,[DiskResultsBuffer+2] MOV CL,8 CALL ToHex MOV SI,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,TheEndOfTheLine CALL PrintString MOV DL,[DiskResultsBuffer+2] MOV [CDDriveNumber],DL MOV DL,[CDDriveNumber] ; Prepare to read CD-ROM, load boot drive MOV AH,41h ; Use function 41h MOV BX,55AAh ; Signature? INT 13h ; Call Check Extensions Present? JC Failure ; Nope, get out of here... ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Need to save the return here: ;; AH = Major Version Number ;; BX = 0AA55h ;; CX = Interface support bitmask: ;; 1 - Device Access using packet structure (assumed by me) ;; 2 - Drive Locking and Ejecting ;; 4 - Enhanced Disk Drive Support ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; MOV AX,CX MOV CL,16 CALL ToHex MOV SI,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,IsEqualToTheCX CALL PrintString MOV SI,MessageReadTheDrive call PrintString MOV DL,[CDDriveNumber] ; Set it up again MOV AH,42h ; Read from drive function MOV SI,DiskAddressPacket ; Load SI with address of the Disk Address ; Packet INT 13h ; Call read sector from drive JC Failure ; Nope, hosed, get out ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Need to read sector information for the boot directory. ;; The Disk Address Packet starts with: ;; db 10h - Initial Volume Descriptor, which has the important data we need ;; to get to the root directory where our OS is stored. ;; db 0 - Unused, should be zero ;; dw 1 - Number of sectors to read (initial one should be one) ;; dd 1000:0000 - Initial segment:offset where to load the read in sector(S) ;; dq 16 - Starting sector to read in, then we need to get to the root directory ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; MOV ES,[DiskAddressPacket.Segment] MOV DI,[DiskAddressPacket.Offset] MOV EAX,[ES:DI+158] ; LBA of root directory, where all things start. MOV CL,32 CALL ToHex MOV SI,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,IsEqualToTheEAX CALL PrintString MOV SI,MessageReadTheDrive call PrintString Failure: mov AL,AH ; Put the error into lowest bits mov cl,8 ; only 8 bits call ToHex ; Get what is in the XX to display MOV SI,FailureMessage ; reboot message CALL PrintString mov si,HexBuffer CALL PrintString MOV SI,AddTheHAtTheEnd CALL PrintString MOV SI,TheEndOfTheLine CALL PrintString mov SI,PressAnyKeyMessage CALL PrintString MOV AH,0 ; Reboot on error INT 16h ; BIOS GetKey INT 19h ; BIOS Reboot ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; PrintString ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; PrintString: PUSHA ; Save Registers .Loop: LODSB ; Load SI into AL, increment SI one byte OR AL,AL ; AL = 0? JZ .Done ; If yes, get out MOV AH,0Eh MOV BH,0 MOV BL,7 ; character attribute INT 10h ; Display character in AL JMP .Loop ; Do it again .Done: POPA ; Replace registers RET ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; PrintMyDot - Increments through the numbers in order to see the number of ;; ;; sectors that have been loaded. ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; PrintMyDot: mov ah,0Eh mov al,[BootDotNumber] int 10h inc al cmp al,58 jb .PDExit mov al,'0' .PDExit: mov [BootDotNumber],al ret ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ToHex ;; Loads HexBuffer with ASCII corresponding to 8, 16, or 32 bit interger in ;; hex. ;; Requires interger in AL, AX, or EAX depending on bit size ;; Requires the number of bits in the CL ;; Returns a full buffer or an empty buffer on error ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ToHex: pusha MOV BX,0x0000 ; Load BX with pointer offset MOV [TheEAX],EAX ; Save the EAX MOV [TheCL],CL ; Save the CL CMP CL,0x08 ; Check for 8 bits JNE .Check16 JMP .Loop1 ; Start loading the buffer .Check16: CMP CL,0x10 ; Check for 16 bits JNE .Check32 JMP .Loop1 ; Start loading the buffer .Check32: CMP CL,0x20 ; Check for 32 bits JNE .ErrorBits .Loop1: MOV EAX,[TheEAX] ; Reload EAX with the converter SUB CL,0x04 ; Lower bit count by 4 bits SHR EAX,CL AND AL,0x0F ADD AL,'0' CMP AL,'9' JBE .LoadBuff1 ADD AL,'A'-'0'-10 ; Convert to "A" to "F" JMP .LoadBuff1 .Loop2: MOV EAX,[TheEAX] ; Reload EAX again SUB CL,4 ; Lower bit count by 8 bits SHR EAX,CL AND AL,0x0F ADD AL,'0' CMP AL,'9' JBE .LoadBuff2 ADD AL,'A'-'0'-10 ; Convert A,B,C,D,E,F JMP .LoadBuff2 .LoadBuff1: MOV [HexBuffer+BX],AL ; Load buffer with AL INC BX ; Increment buffer pointer JMP .Loop2 ; Do next byte .LoadBuff2: MOV [HexBuffer+BX],AL ; Load buffer with AL INC BX ; Increment buffer pointer CMP CL,0x00 ; Check if we're done JNE .Loop1 ; Do next Byte .ErrorBits: MOV AL,0x00 MOV [HexBuffer+BX],AL ; End the string with a zero popa RET ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Program Data ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; DataSector: DW 0 CDDriveNumber: db 0 absoluteSector: DB 0 absoluteHead: DB 0 absoluteTrack: DB 0 BootDotNumber: DB '1' Cluster: DW 0 FileName: DB 'SMIDDYOS.SYS' ; FAT Filename, 8.3, or 11 characters DiskResultsBufferMessage: db 'Disk Buffer on in here...',13,10,0 IsEqualToTheCX db ' = CX contents from INT 13h Function 41h.',13,10,0 IsEqualToTheEAX db ' = EAX contents is the sector of the root directory contents.',13,10,0 WelcomeMessage: DB 'smiddy OS CD boot v1.00a',13,10,0 ; Saving space. MessageReadTheDrive: db 'Read the Drive, free and clear, make it hap',"'",'n cap',"'",'n!',13,10,0 FailureMessage: db 'Failure: ',0 DriveNumberReported: db 'Drive number reported: ',0 PressAnyKeyMessage: db 'Press any key to reboot...',13,10,0 AddTheHAtTheEnd: db 'h',0 TheEndOfTheLine: db 13,10,0 ; Used to print the end of the line string SizeOfPacketInBytes: db 'The size of packet in bytes: ',0 BootMediaType: db 'The boot media type: ',0 DriveNumberFromPacket: db 'Drive number from packet: ',0 DiskAddressPacket: db 16,0 dw 1 .Offset: dw 0 ; Offset :0000 .Segment: dw 1000h ; Segment 1000: .End: dq 16 ; Sector 16 or 10h on CD-ROM DiskResultsBuffer: times 30 db 0 ; Return buffer from int 13h ah=48h HexBuffer: DB 0,0,0,0,0,0,0,0,0 ; Buffer for hex text string TheEAX: dd 0 ; Saves EAX TheCL: db 0 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; 512 Byte Code Boot Signature ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; TIMES 2046-($-BootSector) DB 0 DW 0AA55h ; Bootloading sector signature (for CD/DVD/BD) This works on VirtualBox, Virtual PC, but not on VM Ware 8.0 or my main PC, and a Dell XPS One. It does work on Legacy PCs that I have. I need to figure out why it doesn't on the others. I am guessing it needs UDF and a bootable version at that, which I will research next. I should have the CDFS from this legacy CD-ROM style setup in the next week or so, so I can sort thru directories and load files. Enjoy! |
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14 Nov 2011, 04:22 |
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bitshifter 14 Nov 2011, 19:40
Thanks for sharing your code.
I will try it on a few machines and report results... |
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14 Nov 2011, 19:40 |
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