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Code: Select all

mov edi, packetCommand
	xor eax, eax
	mov ecx, 12
	rep stosb
	mov [packetCommand], byte 0xA8
	mov dword [packetCommand+2], 10000000h  ;16th  sector
	mov dword [packetCommand+6], 01000000h  ;1 sectors to read
	mov [packetSize], 12                                 ;packet size is 12 bytes
	call sendDataPacket

Code: Select all

sendDataPacket:
	pusha
	mov     [ATAFeatures],0
    mov     [ATASectorsCount],0
	mov     [ATASectorNumber],
	mov     AX,[CDBlockSize]
	mov     [ATACylinder],AX
	mov     [ATAHead],0
	mov     [ATACommand],0A0h
	call    sendCommandToHDD
	cmp     [devErrorCode],0 ;
	jne .error
	xor eax, eax
	mov al, [channel]
	shl eax, 2
	mov dx, [basePort+eax]
	add dx, 7
	mov ecx, 0xFFF
@@:
	dec ecx
	jz .error
	in      AL,DX
	test    AL,80h   ;BSY
	jnz     @b
	test    AL,1     ;ERR
	jnz     @b
	test    AL,08h   ; DRQ
	jz      @b
	
	sub dx, 7
	movzx ecx, [packetSize]
	shr ecx, 1
	mov esi, packetCommand
	xchg bx, bx
@@:
	rep outsw
	
	add dx, 7
	mov ecx, 0xFFF
@@:
	dec ecx
	jz .error
	in      AL,DX                     ;device returns 0xD
	test    AL,80h   ;BSY
	jnz     @b
	test    AL,1     ;ERR
	jnz     @b
	test    AL,08h   ;DRQ
	jz      @b
	
	mov edi, CDDataBuf
	movzx ecx, [CDBlockSize]
	shr ecx, 1
	rep insw
	
	mov [devErrorCode], 0
	popa 
	ret
.error:
	mov [devErrorCode], 1
	popa
	ret

Code: Select all

mov     byte[packetCommand],028h
        
	mov     AX,word [CDSectorAddress+2]
    xchg    AL,AH
	mov     word [ packetCommand+2],AX
	mov     AX,word [CDSectorAddress]
	xchg    AL,Ah
	mov     word [packetCommand+4],AX

	mov     byte [packetCommand+8],1
        call    sendDataPacket
	mov esi, CDDataBuf
	mov edi, 0xB8000
	mov ecx, 2048
	mov ah, 0xE
@@:
	lodsb
	stosw
	loop @b
	jmp $
packetSize db 10
packetCommand   DB 12 DUP (0)

CDBlockSize     DW 2048

CDSectorAddress DD 16
align 16
CDDataBuf       DB 4096 DUP (' ')