[54] | 1 | ; Project name : Assembly Library |
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| 2 | ; Description : Functions for register operations. |
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| 3 | |
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[376] | 4 | ; |
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| 5 | ; XTIDE Universal BIOS and Associated Tools |
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| 6 | ; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2012 by XTIDE Universal BIOS Team. |
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| 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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| 12 | ; |
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| 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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| 16 | ; GNU General Public License for more details. |
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| 17 | ; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html |
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| 18 | ; |
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| 19 | |
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[54] | 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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| 24 | ; Registers_ExchangeDSSIwithESDI |
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| 25 | ; Parameters |
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| 26 | ; Nothing |
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| 27 | ; Returns: |
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| 28 | ; DS:SI and ES:DI are exchanged. |
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| 29 | ; Corrupts registers: |
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| 30 | ; Nothing |
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| 31 | ;-------------------------------------------------------------------- |
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| 32 | ALIGN JUMP_ALIGN |
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| 33 | Registers_ExchangeDSSIwithESDI: |
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| 34 | push ds |
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| 35 | push es |
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| 36 | pop ds |
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| 37 | pop es |
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| 38 | xchg si, di |
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| 39 | ret |
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| 40 | |
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| 41 | |
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| 42 | ;-------------------------------------------------------------------- |
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| 43 | ; Registers_CopySSBPtoESDI |
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[106] | 44 | ; Registers_CopySSBPtoDSSI |
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| 45 | ; Registers_CopyDSSItoESDI |
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| 46 | ; Registers_CopyESDItoDSSI |
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[54] | 47 | ; Parameters |
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| 48 | ; Nothing |
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| 49 | ; Returns: |
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| 50 | ; Copies farm pointer to different segment/pointer register pair |
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| 51 | ; Corrupts registers: |
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| 52 | ; Nothing |
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| 53 | ;-------------------------------------------------------------------- |
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[105] | 54 | ALIGN JUMP_ALIGN |
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| 55 | Registers_CopySSBPtoESDI: |
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| 56 | COPY_SSBP_TO_ESDI |
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| 57 | ret |
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[54] | 58 | |
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[131] | 59 | %ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS |
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[106] | 60 | ALIGN JUMP_ALIGN |
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| 61 | Registers_CopySSBPtoDSSI: |
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| 62 | COPY_SSBP_TO_DSSI |
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| 63 | ret |
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[54] | 64 | |
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[106] | 65 | ALIGN JUMP_ALIGN |
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| 66 | Registers_CopyDSSItoESDI: |
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| 67 | COPY_DSSI_TO_ESDI |
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| 68 | ret |
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[54] | 69 | |
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[106] | 70 | ALIGN JUMP_ALIGN |
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| 71 | Registers_CopyESDItoDSSI: |
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| 72 | COPY_ESDI_to_DSSI |
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| 73 | ret |
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| 74 | %endif |
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| 75 | |
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| 76 | |
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[54] | 77 | ;-------------------------------------------------------------------- |
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[149] | 78 | ; Registers_NormalizeESSI |
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| 79 | ; Registers_NormalizeESDI |
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| 80 | ; Parameters |
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| 81 | ; DS:SI or ES:DI: Ptr to normalize |
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| 82 | ; Returns: |
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| 83 | ; DS:SI or ES:DI: Normalized pointer |
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| 84 | ; Corrupts registers: |
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| 85 | ; AX, CX |
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[370] | 86 | ; |
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| 87 | ; Inline of NORMALIZE_FAR_POINTER so that we can share the last 2/3 of the |
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[207] | 88 | ; routine with Registers_NormalizeFinish. |
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[370] | 89 | ; |
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[149] | 90 | ;-------------------------------------------------------------------- |
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[370] | 91 | %ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS OR EXCLUDE_FROM_XTIDECFG |
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[149] | 92 | ALIGN JUMP_ALIGN |
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| 93 | Registers_NormalizeESSI: |
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[207] | 94 | mov cx, si |
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| 95 | and si, byte 0fh |
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| 96 | jmp Registers_NormalizeFinish |
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[149] | 97 | |
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| 98 | ALIGN JUMP_ALIGN |
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| 99 | Registers_NormalizeESDI: |
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[207] | 100 | mov cx, di |
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| 101 | and di, byte 0fh |
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| 102 | ;;; fall-through |
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| 103 | |
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[370] | 104 | ALIGN JUMP_ALIGN |
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| 105 | Registers_NormalizeFinish: |
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[207] | 106 | eSHR_IM cx, 4 |
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| 107 | mov ax, es |
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| 108 | add ax, cx |
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| 109 | mov es, ax |
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[149] | 110 | ret |
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[222] | 111 | %endif |
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[149] | 112 | |
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[222] | 113 | |
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[149] | 114 | ;-------------------------------------------------------------------- |
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[106] | 115 | ; Registers_SetZFifNullPointerInDSSI (commented to save bytes) |
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[54] | 116 | ; Parameters |
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| 117 | ; DS:SI: Far pointer |
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| 118 | ; Returns: |
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| 119 | ; ZF: Set if NULL pointer in DS:SI |
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| 120 | ; Corrupts registers: |
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| 121 | ; Nothing |
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| 122 | ;-------------------------------------------------------------------- |
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[105] | 123 | ;ALIGN JUMP_ALIGN |
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| 124 | ;Registers_SetZFifNullPointerInDSSI: |
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| 125 | ; push ax |
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| 126 | ; mov ax, ds |
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| 127 | ; or ax, si |
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| 128 | ; pop ax |
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| 129 | ; ret |
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