1 | ; Project name : XTIDE Universal BIOS |
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2 | ; Description : Int 13h handler that is used to initialize |
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3 | ; XTIDE Universal BIOS when our INT 19h was not called. |
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4 | |
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5 | ; |
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6 | ; XTIDE Universal BIOS and Associated Tools |
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7 | ; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2013 by XTIDE Universal BIOS Team. |
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8 | ; |
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9 | ; This program is free software; you can redistribute it and/or modify |
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10 | ; it under the terms of the GNU General Public License as published by |
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11 | ; the Free Software Foundation; either version 2 of the License, or |
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12 | ; (at your option) any later version. |
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13 | ; |
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14 | ; This program is distributed in the hope that it will be useful, |
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15 | ; but WITHOUT ANY WARRANTY; without even the implied warranty of |
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16 | ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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17 | ; GNU General Public License for more details. |
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18 | ; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html |
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19 | ; |
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20 | |
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21 | ; Section containing code |
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22 | SECTION .text |
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23 | |
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24 | TEMPORARY_VECTOR_FOR_SYSTEM_INT13h EQU 21h ; MS-DOS |
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25 | |
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26 | |
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27 | Int13hBiosInit_Handler: |
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28 | LOAD_BDA_SEGMENT_TO ds, ax |
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29 | |
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30 | ; Now install our handler and call 19h since non-standard motherboard BIOS did not |
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31 | ; do that or our INT 19h hander was replaced by other BIOS. |
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32 | mov WORD [BIOS_BOOT_LOADER_INTERRUPT_19h*4], Int19h_BootLoaderHandler |
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33 | mov [BIOS_BOOT_LOADER_INTERRUPT_19h*4+2], cs |
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34 | int BIOS_BOOT_LOADER_INTERRUPT_19h ; Does not return |
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35 | |
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36 | |
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37 | ;-------------------------------------------------------------------- |
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38 | ; Int13hBiosInit_RestoreSystemHandler |
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39 | ; Parameters: |
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40 | ; Nothing |
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41 | ; Returns: |
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42 | ; Nothing |
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43 | ; Corrupts registers: |
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44 | ; AX, DS, ES |
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45 | ;-------------------------------------------------------------------- |
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46 | Int13hBiosInit_RestoreSystemHandler: |
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47 | LOAD_BDA_SEGMENT_TO ds, ax |
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48 | |
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49 | ; Is our very late init handler in place |
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50 | cmp WORD [BIOS_DISK_INTERRUPT_13h*4], Int13hBiosInit_Handler |
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51 | jne SHORT .SystemHandlerAlreadyInPlace |
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52 | |
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53 | les ax, [TEMPORARY_VECTOR_FOR_SYSTEM_INT13h*4] |
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54 | mov [BIOS_DISK_INTERRUPT_13h*4], ax |
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55 | mov [BIOS_DISK_INTERRUPT_13h*4+2], es |
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56 | .SystemHandlerAlreadyInPlace: |
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57 | ret |
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