| 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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