[150] | 1 | ; Project name : XTIDE Universal BIOS |
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[3] | 2 | ; Description : Functions for finding Disk Parameter Table. |
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| 3 | |
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[376] | 4 | ; |
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[526] | 5 | ; XTIDE Universal BIOS and Associated Tools |
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| 6 | ; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2013 by XTIDE Universal BIOS Team. |
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[376] | 7 | ; |
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| 8 | ; This program is free software; you can redistribute it and/or modify |
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| 9 | ; it under the terms of the GNU General Public License as published by |
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| 10 | ; the Free Software Foundation; either version 2 of the License, or |
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| 11 | ; (at your option) any later version. |
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[526] | 12 | ; |
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[376] | 13 | ; This program is distributed in the hope that it will be useful, |
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| 14 | ; but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 15 | ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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[526] | 16 | ; GNU General Public License for more details. |
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[376] | 17 | ; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html |
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[526] | 18 | ; |
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[376] | 19 | |
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[3] | 20 | ; Section containing code |
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| 21 | SECTION .text |
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| 22 | |
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| 23 | ;-------------------------------------------------------------------- |
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[262] | 24 | ; Checks if drive is handled by this BIOS, and return DPT pointer. |
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[3] | 25 | ; |
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[294] | 26 | ; FindDPT_ForDriveNumberInDL |
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[3] | 27 | ; Parameters: |
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[262] | 28 | ; DL: Drive number |
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[3] | 29 | ; DS: RAMVARS segment |
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| 30 | ; Returns: |
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[262] | 31 | ; CF: Cleared if drive is handled by this BIOS |
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| 32 | ; Set if drive belongs to some other BIOS |
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| 33 | ; DI: DPT Pointer if drive is handled by this BIOS |
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| 34 | ; Zero if drive belongs to some other BIOS |
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[3] | 35 | ; Corrupts registers: |
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[262] | 36 | ; Nothing |
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[150] | 37 | ;-------------------------------------------------------------------- |
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| 38 | ALIGN JUMP_ALIGN |
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[294] | 39 | FindDPT_ForDriveNumberInDL: |
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[262] | 40 | xchg di, ax ; Save the contents of AX in DI |
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| 41 | |
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[294] | 42 | ; |
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[262] | 43 | ; Check Our Hard Disks |
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| 44 | ; |
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[433] | 45 | mov ax, [RAMVARS.wFirstDrvAndCount] ; Drive count to AH, First number to AL |
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[262] | 46 | add ah, al ; One past last drive to AH |
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| 47 | |
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[258] | 48 | %ifdef MODULE_SERIAL_FLOPPY |
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[262] | 49 | cmp dl, ah ; Above last supported? |
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| 50 | jae SHORT .HardDiskNotHandledByThisBIOS |
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[294] | 51 | |
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[262] | 52 | cmp dl, al ; Below first supported? |
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| 53 | jae SHORT .CalcDPTForDriveNumber |
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| 54 | |
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[294] | 55 | ALIGN JUMP_ALIGN |
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| 56 | .HardDiskNotHandledByThisBIOS: |
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[262] | 57 | ; |
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| 58 | ; Check Our Floppy Disks |
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[294] | 59 | ; |
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[262] | 60 | call RamVars_UnpackFlopCntAndFirstToAL |
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| 61 | js SHORT .DiskIsNotHandledByThisBIOS |
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[294] | 62 | |
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[277] | 63 | cbw ; Always 0h (no floppy drive covered above) |
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| 64 | adc ah, al ; Add in first drive number and number of drives |
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| 65 | |
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[262] | 66 | cmp ah, dl ; Check second drive if two, first drive if only one |
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| 67 | jz SHORT .CalcDPTForDriveNumber |
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| 68 | cmp al, dl ; Check first drive in all cases, redundant but OK to repeat |
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[294] | 69 | jnz SHORT .DiskIsNotHandledByThisBIOS |
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[262] | 70 | %else |
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[294] | 71 | cmp dl, ah ; Above last supported? |
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[262] | 72 | jae SHORT .DiskIsNotHandledByThisBIOS |
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[294] | 73 | |
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[262] | 74 | cmp dl, al ; Below first supported? |
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[294] | 75 | jb SHORT .DiskIsNotHandledByThisBIOS |
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[258] | 76 | %endif |
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[567] | 77 | ; Fall to .CalcDPTForDriveNumber |
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[150] | 78 | |
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| 79 | ;-------------------------------------------------------------------- |
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| 80 | ; Finds Disk Parameter Table for drive number. |
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[294] | 81 | ; Not intended to be called except by FindDPT_ForDriveNumberInDL |
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[150] | 82 | ; |
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[567] | 83 | ; .CalcDPTForDriveNumber |
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[150] | 84 | ; Parameters: |
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| 85 | ; DL: Drive number |
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| 86 | ; DS: RAMVARS segment |
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[567] | 87 | ; DI: Saved copy of AX from entry at FindDPT_ForDriveNumberInDL |
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[150] | 88 | ; Returns: |
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| 89 | ; DS:DI: Ptr to DPT |
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[567] | 90 | ; CF: Clear |
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[150] | 91 | ; Corrupts registers: |
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[3] | 92 | ; Nothing |
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| 93 | ;-------------------------------------------------------------------- |
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| 94 | ALIGN JUMP_ALIGN |
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[262] | 95 | .CalcDPTForDriveNumber: |
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[150] | 96 | push dx |
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[3] | 97 | |
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[258] | 98 | %ifdef MODULE_SERIAL_FLOPPY |
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[433] | 99 | mov ax, [RAMVARS.wFirstDrvAndCount] |
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[294] | 100 | |
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[258] | 101 | test dl, dl |
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| 102 | js .harddisk |
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| 103 | |
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| 104 | call RamVars_UnpackFlopCntAndFirstToAL |
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| 105 | add dl, ah ; add in end of hard disk DPT list, floppies start immediately after |
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[294] | 106 | |
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| 107 | ALIGN JUMP_ALIGN |
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[258] | 108 | .harddisk: |
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| 109 | sub dl, al ; subtract off beginning of either hard disk or floppy list (as appropriate) |
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| 110 | %else |
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| 111 | sub dl, [RAMVARS.bFirstDrv] ; subtract off beginning of hard disk list |
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| 112 | %endif |
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[262] | 113 | |
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[294] | 114 | .CalcDPTForNewDrive: |
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[150] | 115 | mov al, LARGEST_DPT_SIZE |
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[294] | 116 | |
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[150] | 117 | mul dl |
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[522] | 118 | add ax, RAMVARS_size ; Clears CF (will not overflow) |
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[3] | 119 | |
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[150] | 120 | pop dx |
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[262] | 121 | |
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| 122 | xchg di, ax ; Restore AX from entry at FindDPT_ForDriveNumber, put DPT pointer in DI |
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[150] | 123 | ret |
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| 124 | |
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[294] | 125 | ALIGN JUMP_ALIGN |
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| 126 | .DiskIsNotHandledByThisBIOS: |
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[259] | 127 | ; |
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[262] | 128 | ; Drive not found... |
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| 129 | ; |
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| 130 | xor ax, ax ; Clear DPT pointer |
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[294] | 131 | stc ; Is not supported by our BIOS |
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| 132 | |
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[262] | 133 | xchg di, ax ; Restore AX from save at top |
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[259] | 134 | ret |
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| 135 | |
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[271] | 136 | |
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[259] | 137 | ;-------------------------------------------------------------------- |
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[521] | 138 | ; Iteration routines for FindDPT_MasterOrSingleForIdevarsOffsetInDL and |
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[621] | 139 | ; FindDPT_SlaveForIdevarsOffsetInDL, for use with FindDPT_IterateAllDPTs |
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[294] | 140 | ; |
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[271] | 141 | ; Returns when DPT is found on the controller with Idevars offset in DL |
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| 142 | ; |
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[521] | 143 | ; IterateFindSecondDPTforIdevars |
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[271] | 144 | ; IterateFindFirstDPTforIdevars |
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[567] | 145 | ; DL: Offset to IDEVARS to search from DPTs |
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[524] | 146 | ; SI: Offset to this callback function |
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[271] | 147 | ; DS:DI: Ptr to DPT to examine |
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| 148 | ; Returns: |
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[567] | 149 | ; CF: Cleared if wanted DPT found |
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[271] | 150 | ; Set if wrong DPT |
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| 151 | ;-------------------------------------------------------------------- |
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[521] | 152 | IterateFindSecondDPTforIdevars: |
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| 153 | call IterateFindFirstDPTforIdevars |
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[621] | 154 | jc SHORT WrongController |
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[524] | 155 | mov si, IterateFindFirstDPTforIdevars |
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[621] | 156 | SetCFandReturn: |
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[524] | 157 | stc |
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[621] | 158 | WrongController: |
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[524] | 159 | ret |
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[521] | 160 | |
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[294] | 161 | IterateFindFirstDPTforIdevars: |
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[271] | 162 | cmp dl, [di+DPT.bIdevarsOffset] ; Clears CF if matched |
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[621] | 163 | jne SHORT SetCFandReturn |
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[271] | 164 | ret |
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| 165 | |
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| 166 | |
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| 167 | ;-------------------------------------------------------------------- |
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[262] | 168 | ; Finds pointer to first unused Disk Parameter Table. |
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| 169 | ; Should only be used before DetectDrives is complete (not valid after this time). |
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[3] | 170 | ; |
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[262] | 171 | ; FindDPT_ForNewDriveToDSDI |
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[3] | 172 | ; Parameters: |
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| 173 | ; DS: RAMVARS segment |
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| 174 | ; Returns: |
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[262] | 175 | ; DS:DI: Ptr to first unused DPT |
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[3] | 176 | ; Corrupts registers: |
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[262] | 177 | ; AX |
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[3] | 178 | ;-------------------------------------------------------------------- |
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[262] | 179 | ALIGN JUMP_ALIGN |
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| 180 | FindDPT_ForNewDriveToDSDI: |
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| 181 | push dx |
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[294] | 182 | |
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[262] | 183 | %ifdef MODULE_SERIAL_FLOPPY |
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| 184 | mov dx, [RAMVARS.wDrvCntAndFlopCnt] |
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| 185 | add dl, dh |
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| 186 | %else |
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| 187 | mov dl, [RAMVARS.bDrvCnt] |
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| 188 | %endif |
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[294] | 189 | |
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[567] | 190 | jmp SHORT FindDPT_ForDriveNumberInDL.CalcDPTForNewDrive |
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[3] | 191 | |
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[152] | 192 | ;-------------------------------------------------------------------- |
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[233] | 193 | ; IterateToDptWithFlagsHighInBL |
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[152] | 194 | ; Parameters: |
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| 195 | ; DS:DI: Ptr to DPT to examine |
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[567] | 196 | ; BL: Bit(s) to test in DPT.bFlagsHigh |
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[152] | 197 | ; Returns: |
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[567] | 198 | ; CF: Cleared if wanted DPT found |
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[262] | 199 | ; Set if wrong DPT |
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[152] | 200 | ; Corrupts registers: |
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| 201 | ; Nothing |
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| 202 | ;-------------------------------------------------------------------- |
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[567] | 203 | %ifdef MODULE_SERIAL |
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[152] | 204 | ALIGN JUMP_ALIGN |
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[294] | 205 | IterateToDptWithFlagsHighInBL: |
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| 206 | test [di+DPT.bFlagsHigh], bl ; Clears CF |
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[262] | 207 | jnz SHORT .ReturnRightDPT |
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| 208 | stc |
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[294] | 209 | .ReturnRightDPT: |
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[3] | 210 | ret |
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[567] | 211 | %endif |
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[3] | 212 | |
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| 213 | ;-------------------------------------------------------------------- |
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[233] | 214 | ; FindDPT_ToDSDIforSerialDevice |
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[161] | 215 | ; Parameters: |
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| 216 | ; DS: RAMVARS segment |
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| 217 | ; Returns: |
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| 218 | ; DS:DI: Ptr to DPT |
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[567] | 219 | ; CF: Cleared if wanted DPT found |
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| 220 | ; Set if DPT not found, or no DPTs present |
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[161] | 221 | ; Corrupts registers: |
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[621] | 222 | ; BL, SI |
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[161] | 223 | ;-------------------------------------------------------------------- |
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[265] | 224 | %ifdef MODULE_SERIAL |
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[294] | 225 | ALIGN JUMP_ALIGN |
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| 226 | FindDPT_ToDSDIforSerialDevice: |
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[233] | 227 | mov bl, FLGH_DPT_SERIAL_DEVICE |
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[567] | 228 | ; Fall to FindDPT_ToDSDIforFlagsHighInBL |
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[265] | 229 | %endif |
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[294] | 230 | |
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[233] | 231 | ;-------------------------------------------------------------------- |
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[567] | 232 | ; FindDPT_ToDSDIforFlagsHighInBL |
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[233] | 233 | ; Parameters: |
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| 234 | ; DS: RAMVARS segment |
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[567] | 235 | ; BL: Bit(s) to test in DPT.bFlagsHigh |
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[233] | 236 | ; Returns: |
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| 237 | ; DS:DI: Ptr to DPT |
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[567] | 238 | ; CF: Cleared if wanted DPT found |
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| 239 | ; Set if DPT not found, or no DPTs present |
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[233] | 240 | ; Corrupts registers: |
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| 241 | ; SI |
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| 242 | ;-------------------------------------------------------------------- |
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[567] | 243 | %ifdef MODULE_SERIAL |
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| 244 | ;%ifdef MODULE_IRQ |
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| 245 | ;ALIGN JUMP_ALIGN |
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| 246 | ;FindDPT_ToDSDIforFlagsHighInBL: ; This label is unused |
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| 247 | ;%endif |
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| 248 | mov si, IterateToDptWithFlagsHighInBL |
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| 249 | jmp SHORT FindDPT_IterateAllDPTs |
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[489] | 250 | %endif |
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[161] | 251 | |
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| 252 | ;-------------------------------------------------------------------- |
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[567] | 253 | ; FindDPT_MasterOrSingleForIdevarsOffsetInDL |
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| 254 | ; Parameters: |
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| 255 | ; DL: Offset to IDEVARS to search for |
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| 256 | ; DS: RAMVARS segment |
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| 257 | ; Returns: |
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| 258 | ; DS:DI: Ptr to first DPT with same IDEVARS as in DL |
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| 259 | ; CF: Cleared if wanted DPT found |
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| 260 | ; Set if DPT not found, or no DPTs present |
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| 261 | ; Corrupts registers: |
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| 262 | ; SI |
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| 263 | ;-------------------------------------------------------------------- |
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| 264 | FindDPT_MasterOrSingleForIdevarsOffsetInDL: |
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| 265 | mov si, IterateFindFirstDPTforIdevars |
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| 266 | jmp SHORT FindDPT_IterateAllDPTs |
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| 267 | |
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| 268 | ;-------------------------------------------------------------------- |
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| 269 | ; FindDPT_SlaveForIdevarsOffsetInDL |
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| 270 | ; Parameters: |
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| 271 | ; DL: Offset to IDEVARS to search for |
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| 272 | ; DS: RAMVARS segment |
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| 273 | ; Returns: |
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| 274 | ; DS:DI: Ptr to second DPT with same IDEVARS as in DL |
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| 275 | ; CF: Cleared if wanted DPT found |
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| 276 | ; Set if DPT not found, or no DPTs present |
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| 277 | ; Corrupts registers: |
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| 278 | ; SI |
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| 279 | ;-------------------------------------------------------------------- |
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| 280 | FindDPT_SlaveForIdevarsOffsetInDL: |
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| 281 | mov si, IterateFindSecondDPTforIdevars |
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| 282 | ; Fall to FindDPT_IterateAllDPTs |
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| 283 | |
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| 284 | ;-------------------------------------------------------------------- |
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[3] | 285 | ; Iterates all Disk Parameter Tables. |
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| 286 | ; |
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[271] | 287 | ; FindDPT_IterateAllDPTs |
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[3] | 288 | ; Parameters: |
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[152] | 289 | ; AX,BX,DX: Parameters to callback function |
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| 290 | ; CS:SI: Ptr to callback function |
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[567] | 291 | ; Callback routine should return CF=clear if found |
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[152] | 292 | ; DS: RAMVARS segment |
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[3] | 293 | ; Returns: |
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[152] | 294 | ; DS:DI: Ptr to wanted DPT (if found) |
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[258] | 295 | ; If not found, points to first empty DPT |
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[567] | 296 | ; CF: Cleared if wanted DPT found |
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[262] | 297 | ; Set if DPT not found, or no DPTs present |
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[3] | 298 | ; Corrupts registers: |
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[150] | 299 | ; Nothing unless corrupted by callback function |
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[3] | 300 | ;-------------------------------------------------------------------- |
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| 301 | ALIGN JUMP_ALIGN |
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[271] | 302 | FindDPT_IterateAllDPTs: |
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[3] | 303 | push cx |
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[258] | 304 | |
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| 305 | mov di, RAMVARS_size ; Point DS:DI to first DPT |
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[294] | 306 | eMOVZX cx, [RAMVARS.bDrvCnt] |
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[262] | 307 | jcxz .NotFound ; Return if no drives |
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[294] | 308 | |
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[3] | 309 | ALIGN JUMP_ALIGN |
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| 310 | .LoopWhileDPTsLeft: |
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| 311 | call si ; Is wanted DPT? |
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[262] | 312 | jnc SHORT .Found ; If so, return |
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| 313 | add di, BYTE LARGEST_DPT_SIZE ; Point to next DPT |
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[258] | 314 | loop .LoopWhileDPTsLeft |
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[262] | 315 | |
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| 316 | .NotFound: |
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| 317 | stc |
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| 318 | |
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| 319 | ALIGN JUMP_ALIGN |
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| 320 | .Found: |
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[3] | 321 | pop cx |
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| 322 | ret |
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