[3] | 1 | ; File name : AH8h_HParams.asm |
---|
| 2 | ; Project name : IDE BIOS |
---|
| 3 | ; Created date : 27.9.2007 |
---|
[43] | 4 | ; Last update : 24.9.2010 |
---|
[3] | 5 | ; Author : Tomi Tilli |
---|
| 6 | ; Description : Int 13h function AH=8h, Read Disk Drive Parameters. |
---|
| 7 | |
---|
| 8 | ; Section containing code |
---|
| 9 | SECTION .text |
---|
| 10 | |
---|
| 11 | ;-------------------------------------------------------------------- |
---|
| 12 | ; Int 13h function AH=8h, Read Disk Drive Parameters. |
---|
| 13 | ; |
---|
| 14 | ; AH8h_HandlerForReadDiskDriveParameters |
---|
| 15 | ; Parameters: |
---|
| 16 | ; AH: Bios function 8h |
---|
| 17 | ; DL: Drive number |
---|
| 18 | ; Parameters loaded by Int13h_Jump: |
---|
| 19 | ; DS: RAMVARS segment |
---|
| 20 | ; Returns: |
---|
| 21 | ; CH: Maximum cylinder number, bits 7...0 |
---|
| 22 | ; CL: Bits 7...6: Cylinder number bits 9...8 |
---|
| 23 | ; Bits 5...0: Maximum sector number (1...63) |
---|
| 24 | ; DH: Maximum head number (0...255) |
---|
| 25 | ; DL: Number of drives |
---|
| 26 | ; AH: Int 13h/40h floppy return status |
---|
| 27 | ; CF: 0 if successfull, 1 if error |
---|
| 28 | ; IF: 1 |
---|
| 29 | ; Corrupts registers: |
---|
| 30 | ; Flags |
---|
| 31 | ;-------------------------------------------------------------------- |
---|
| 32 | ALIGN JUMP_ALIGN |
---|
| 33 | AH8h_HandlerForReadDiskDriveParameters: |
---|
[32] | 34 | call RamVars_IsDriveHandledByThisBIOS |
---|
| 35 | jnc SHORT .GetDriveParametersForForeignHardDiskInDL |
---|
| 36 | |
---|
[3] | 37 | push bx |
---|
| 38 | call AH8h_GetDriveParameters |
---|
| 39 | pop bx |
---|
[35] | 40 | jmp Int13h_ReturnWithValueInDL |
---|
[3] | 41 | |
---|
[32] | 42 | ALIGN JUMP_ALIGN |
---|
| 43 | .GetDriveParametersForForeignHardDiskInDL: |
---|
| 44 | call Int13h_CallPreviousInt13hHandler |
---|
[43] | 45 | jc SHORT .ReturnErrorFromPreviousInt13hHandler |
---|
[32] | 46 | call RamVars_GetCountOfKnownDrivesToDL |
---|
[35] | 47 | jmp Int13h_ReturnWithValueInDL |
---|
[43] | 48 | .ReturnErrorFromPreviousInt13hHandler: |
---|
| 49 | jmp Int13h_PopDiDsAndReturn |
---|
[3] | 50 | |
---|
[32] | 51 | |
---|
[3] | 52 | ;-------------------------------------------------------------------- |
---|
| 53 | ; Returns L-CHS parameters for drive and total hard disk count. |
---|
| 54 | ; |
---|
[28] | 55 | ; AH8h_GetDriveParameters |
---|
[3] | 56 | ; Parameters: |
---|
| 57 | ; DL: Drive number |
---|
| 58 | ; DS: RAMVARS segment |
---|
| 59 | ; Returns: |
---|
| 60 | ; CH: Maximum cylinder number, bits 7...0 |
---|
| 61 | ; CL: Bits 7...6: Cylinder number bits 9...8 |
---|
| 62 | ; Bits 5...0: Maximum sector number (1...63) |
---|
| 63 | ; DH: Maximum head number (0...255) |
---|
| 64 | ; DL: Number of drives |
---|
| 65 | ; DS:DI: Ptr to DPT |
---|
| 66 | ; AH: Int 13h/40h floppy return status |
---|
| 67 | ; CF: 0 if successfull, 1 if error |
---|
| 68 | ; Corrupts registers: |
---|
| 69 | ; AL, BX |
---|
| 70 | ;-------------------------------------------------------------------- |
---|
| 71 | ALIGN JUMP_ALIGN |
---|
| 72 | AH8h_GetDriveParameters: |
---|
| 73 | call FindDPT_ForDriveNumber |
---|
| 74 | call AccessDPT_GetLCHSfromPCHS ; AX=sectors, BX=cylinders, DX=heads |
---|
| 75 | call AH8h_ReserveCylinders |
---|
| 76 | call AH8h_PackReturnValues |
---|
| 77 | xor ax, ax ; Clear AH and CF |
---|
| 78 | ret |
---|
| 79 | |
---|
| 80 | |
---|
| 81 | ;-------------------------------------------------------------------- |
---|
| 82 | ; Reserves diagnostic cylinder if so configured. |
---|
| 83 | ; |
---|
| 84 | ; AH8h_ReserveCylinders |
---|
| 85 | ; Parameters: |
---|
| 86 | ; BX: Total number of L-CHS cylinders available |
---|
| 87 | ; DS:DI: Ptr to DPT |
---|
| 88 | ; Returns: |
---|
| 89 | ; BX: Number of L-CHS cylinders available after reserving |
---|
| 90 | ; Corrupts registers: |
---|
| 91 | ; CX |
---|
| 92 | ;-------------------------------------------------------------------- |
---|
| 93 | ALIGN JUMP_ALIGN |
---|
| 94 | AH8h_ReserveCylinders: |
---|
| 95 | test BYTE [cs:ROMVARS.wFlags], FLG_ROMVARS_MAXSIZE |
---|
| 96 | jnz SHORT .Return |
---|
| 97 | dec bx ; Reserve diagnostic cylinder |
---|
| 98 | ALIGN JUMP_ALIGN |
---|
| 99 | .Return: |
---|
| 100 | ret |
---|
| 101 | |
---|
| 102 | |
---|
| 103 | ;-------------------------------------------------------------------- |
---|
| 104 | ; Packs L-CHS values to INT 13h, AH=08h return values. |
---|
| 105 | ; |
---|
| 106 | ; AH8h_PackReturnValues |
---|
| 107 | ; Parameters: |
---|
| 108 | ; AX: Number of L-CHS sectors per track (1...63) |
---|
| 109 | ; BX: Number of L-CHS cylinders available (1...1024) |
---|
| 110 | ; DX: Number of L-CHS heads (1...256) |
---|
[32] | 111 | ; DS: RAMVARS segment |
---|
[3] | 112 | ; Returns: |
---|
| 113 | ; CH: Maximum cylinder number, bits 7...0 |
---|
| 114 | ; CL: Bits 7...6: Cylinder number bits 9...8 |
---|
| 115 | ; Bits 5...0: Maximum sector number (1...63) |
---|
| 116 | ; DH: Maximum head number (0...255) |
---|
| 117 | ; DL: Number of drives |
---|
| 118 | ; Corrupts registers: |
---|
| 119 | ; AX, BX |
---|
| 120 | ;-------------------------------------------------------------------- |
---|
| 121 | ALIGN JUMP_ALIGN |
---|
| 122 | AH8h_PackReturnValues: |
---|
| 123 | dec bx ; Cylinder count to last cylinder |
---|
| 124 | dec dx ; Head count to max head number |
---|
| 125 | mov dh, dl ; Max head number to DH |
---|
| 126 | mov ch, bl ; Cylinder bits 7...0 to CH |
---|
| 127 | mov cl, bh ; Cylinder bits 9...8 to CL |
---|
| 128 | eROR_IM cl, 2 ; Cylinder bits 9...8 to CL bits 7...6 |
---|
| 129 | or cl, al ; Sectors per track to CL bits 5...0 |
---|
[32] | 130 | jmp RamVars_GetCountOfKnownDrivesToDL |
---|