[3] | 1 | ; File name : AHCh_HSeek.asm
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| 2 | ; Project name : IDE BIOS
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| 3 | ; Created date : 13.12.2007
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| 4 | ; Last update : 12.4.2010
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| 5 | ; Author : Tomi Tilli
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| 6 | ; Description : Int 13h function AH=Ch, Seek.
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| 7 |
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| 8 | ; Section containing code
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| 9 | SECTION .text
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| 10 |
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| 11 | ;--------------------------------------------------------------------
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| 12 | ; Int 13h function AH=Ch, Seek.
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| 13 | ;
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| 14 | ; AHCh_HandlerForSeek
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| 15 | ; Parameters:
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| 16 | ; AH: Bios function Ch
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| 17 | ; CH: Cylinder number, bits 7...0
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| 18 | ; CL: Bits 7...6: Cylinder number bits 9 and 8
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| 19 | ; Bits 5...0: Starting sector number (1...63)
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| 20 | ; DH: Starting head number (0...255)
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| 21 | ; DL: Drive number
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| 22 | ; Parameters loaded by Int13h_Jump:
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| 23 | ; DS: RAMVARS segment
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| 24 | ; Returns:
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| 25 | ; AH: BIOS Error code
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| 26 | ; CF: 0 if succesfull, 1 if error
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| 27 | ; IF: 1
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| 28 | ; Corrupts registers:
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| 29 | ; Flags
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| 30 | ;--------------------------------------------------------------------
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| 31 | ALIGN JUMP_ALIGN
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| 32 | AHCh_HandlerForSeek:
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| 33 | push dx
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| 34 | push cx
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| 35 | push bx
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| 36 | push ax
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| 37 | call AHCh_SeekToCylinder
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| 38 | jmp Int13h_PopXRegsAndReturn
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| 39 |
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| 40 |
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| 41 | ;--------------------------------------------------------------------
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| 42 | ; Seeks to a cylinder.
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| 43 | ;
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| 44 | ; AHCh_SeekToCylinder
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| 45 | ; Parameters:
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| 46 | ; CH: Cylinder number, bits 7...0
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| 47 | ; CL: Bits 7...6: Cylinder number bits 9 and 8
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| 48 | ; Bits 5...0: Starting sector number (1...63)
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| 49 | ; DH: Starting head number (0...255)
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| 50 | ; DL: Drive Number
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| 51 | ; DS: RAMVARS segment
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| 52 | ; Returns:
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| 53 | ; DS:DI: Ptr to DPT
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| 54 | ; AH: BIOS Error code
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| 55 | ; CF: 0 if succesfull, 1 if error
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| 56 | ; Corrupts registers:
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| 57 | ; AL, BX, CX, DX
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| 58 | ;--------------------------------------------------------------------
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| 59 | ALIGN JUMP_ALIGN
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| 60 | AHCh_SeekToCylinder:
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| 61 | call FindDPT_ForDriveNumber ; DS:DI now points to DPT
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| 62 | mov ax, HCMD_SEEK<<8 ; Load cmd to AH, AL=zero sector cnt
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| 63 | call HCommand_OutputCountAndLCHSandCommand
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| 64 | jc SHORT .Return ; Return if error
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| 65 | mov bx, di ; DS:BX now points to DPT
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| 66 | jmp HStatus_WaitIrqOrRdy ; Wait for IRQ or RDY
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| 67 | .Return:
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| 68 | ret
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