source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Inc/RamVars.inc @ 414

Last change on this file since 414 was 414, checked in by aitotat@…, 12 years ago

Changes to XTIDE Universal BIOS:

  • MEMPIOVARS no longer overflow when not building MODULE_EBIOS.
File size: 3.8 KB
Line 
1; Project name  :   XTIDE Universal BIOS
2; Description   :   RAMVARS struct containing BIOS variables stored in RAM.
3
4;
5; XTIDE Universal BIOS and Associated Tools
6; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2012 by XTIDE Universal BIOS Team.
7;
8; This program is free software; you can redistribute it and/or modify
9; it under the terms of the GNU General Public License as published by
10; the Free Software Foundation; either version 2 of the License, or
11; (at your option) any later version.
12;
13; This program is distributed in the hope that it will be useful,
14; but WITHOUT ANY WARRANTY; without even the implied warranty of
15; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16; GNU General Public License for more details.     
17; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
18;
19
20%ifndef RAMVARS_INC
21%define RAMVARS_INC
22
23; Segment when RAMVARS is stored to top of interrupt vectors.
24%ifndef USE_AT
25LITE_MODE_RAMVARS_SEGMENT   EQU     30h
26%endif
27
28; RAM Variables.
29; Variables should be kept to minimum since they might be located
30; at the top of interrupt vectors.
31struc RAMVARS
32    .fpOldI13h          resb    4   ; Far pointer to old INT 13h handler
33    .wSignature         resb    2   ; Sign for finding stolen 1 kiB
34    .bTimeoutTicksLeft  resb    1
35    .bLastTimeoutUpdate resb    1
36
37    .wDrvCntAndFirst:
38    .bFirstDrv          resb    1   ; Number of first drive for this BIOS
39    .wDrvCntAndFlopCnt:             ; Both the hard disk and floppy counts in one word
40                                    ; (yes, misaligned, but it is only used this way during initialization)
41    .bDrvCnt            resb    1   ; Number of drives handled by this BIOS
42
43    ; Variables for drive number translation
44%ifdef MODULE_HOTKEYS
45    .xlateVars          resb    XLATEVARS_size
46%endif
47endstruc
48
49
50; Variables for translating drive numbers.
51%ifdef MODULE_HOTKEYS
52    struc XLATEVARS
53    %ifdef MODULE_SERIAL_FLOPPY
54        .bFlopCreateCnt:
55        .bFlopCntAndFirst   resb    1   ; Normally, packed starting floppy drive number (high order 7 bits)
56                                        ; and number of drives (low order bit, max 2 drives supported).
57                                        ; During initialization, until the end of DetectDrives_FromAllIDEControllers,
58                                        ; this byte contains the raw number of floppy drives seen (using .bFlopCreateCnt)
59    %else
60                            resb    1   ; alignment
61    %endif
62        .bXlatedDrv         resb    1   ; Drive number after translation
63        .wFDandHDswap:
64        .bFDSwap            resb    1   ; Floppy Drive to swap to 00h and vice versa
65        .bHDSwap            resb    1   ; Hard Drive to swap to 80h and vice versa
66    endstruc
67%endif
68
69
70%ifdef MODULE_SERIAL_FLOPPY
71  %ifndef CHECK_FOR_UNUSED_ENTRYPOINTS
72    %if RAMVARS.xlateVars != RAMVARS.bDrvCnt+1 || XLATEVARS.bFlopCreateCnt != 0
73        %error "bFlopCreateCnt needs to be the first thing in XLATEVARS, and .xlateVars needs to come immediately after .bDrvCnt.  In at least one place, we read .wDrvCntAndFlopCnt to get both counts in one fetch"
74    %endif
75  %endif
76%endif
77
78RAMVARS_SIGNATURE       EQU "Xu"    ; RAMVARS signature for .wSignature
79
80;
81; IDEPACK NOTE: The first six bytes of this structure are directly put on the
82; wire for MODULE_SERIAL, please do not change the order or insert other members.
83;
84struc IDEPACK   ; PIOVARS and MEMPIOVARS overwrite the first 7 bytes
85    .bFeatures              resb    1
86    .bDrvAndHead            resb    1   ; LBA28 27...24
87
88    .wSectorCountAndLbaLow:
89    .bSectorCount           resb    1
90    .bSectorNumber:
91    .bLbaLow                resb    1   ; LBA 7...0
92
93    .wCylinder:
94    .wLbaMiddleAndHigh:
95    .bLbaMiddle             resb    1   ; LBA 15...8
96    .bLbaHigh               resb    1   ; LBA 23...16
97
98    .bCommand               resb    1
99    .bDeviceControl         resb    1   ; Offset 7 shared with PIOVARS and MEMPIOVARS
100                            resb    1   ; Used by PIOVARS and MEMPIOVARS
101
102%ifdef MODULE_EBIOS
103    ; Parameters for 48-bit LBA
104    .bLbaLowExt             resb    1   ; LBA48 31...24
105    .wLbaMiddleAndHighExt:
106    .bLbaMiddleExt          resb    1   ; LBA48 39...32
107    .bLbaHighExt            resb    1   ; LBA48 47...40
108%endif
109
110    .intpack                resb    INTPACK_size
111endstruc
112
113EXTRA_BYTES_FOR_INTPACK     EQU (IDEPACK_size - INTPACK_size)
114
115
116%endif ; RAMVARS_INC
Note: See TracBrowser for help on using the repository browser.