source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH8h_HParams.asm@ 465

Last change on this file since 465 was 434, checked in by aitotat@…, 12 years ago

Changes to XTIDE Universal BIOS:

  • Quick fix to AH=00h: Error code is again preserved if entry DL contains foreign drive number.
File size: 6.5 KB
Line 
1; Project name : XTIDE Universal BIOS
2; Description : Int 13h function AH=8h, Read Disk Drive Parameters.
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; Section containing code
21SECTION .text
22
23;--------------------------------------------------------------------
24; Int 13h function AH=8h, Read Disk Drive Parameters.
25;
26; AH8h_HandlerForReadDiskDriveParameters
27; Parameters:
28; DL: Translated Drive number
29; DS:DI: Ptr to DPT (in RAMVARS segment)
30; SS:BP: Ptr to IDEPACK
31; Returns with INTPACK:
32; BL: Drive Type (for floppies only)
33; CH: Maximum cylinder number, bits 7...0
34; CL: Bits 7...6: Cylinder number bits 9...8
35; Bits 5...0: Maximum sector number (1...63)
36; DH: Maximum head number (0...254)
37; DL: Number of drives!!!
38; ES:DI: Floppy DPT (for floppies only)
39; AH: Int 13h/40h floppy return status
40; CF: 0 if successful, 1 if error
41;--------------------------------------------------------------------
42AH8h_HandlerForReadDiskDriveParameters:
43 test di, di
44 jz SHORT .NotOurDrive
45
46 call AH8h_GetDriveParameters
47
48%ifdef MODULE_SERIAL_FLOPPY
49 push cs ; setup registers if we are a floppy drive, in all cases
50 pop es ; if it is not a floppy drive, these values will not be put in INTPACK
51 mov di, AH8h_FloppyDPT
52%endif
53 ;; fall-through
54
55.MidGame:
56 call RamVars_GetCountOfKnownDrivesToAX ; assume hard disk for now, will discard if for floppies
57
58 test byte [bp+IDEPACK.intpack+INTPACK.dl], 080h
59 jnz .Done
60
61 mov [bp+IDEPACK.intpack+INTPACK.bl], bl
62
63 mov [bp+IDEPACK.intpack+INTPACK.es], es
64 mov [bp+IDEPACK.intpack+INTPACK.di], di
65
66 call FloppyDrive_GetCountToAX
67
68.Done:
69 mov ah, dh
70
71 mov [bp+IDEPACK.intpack+INTPACK.cx], cx
72 xchg [bp+IDEPACK.intpack+INTPACK.dx], ax ; recover DL for BDA last status byte determination
73
74 xor ah, ah
75%ifdef MODULE_SERIAL_FLOPPY
76 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH_ALHasDriveNumber
77%else
78 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
79%endif
80
81.NotOurDrive:
82 call Int13h_CallPreviousInt13hHandler
83 jnc SHORT .MidGame
84 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
85
86
87;--------------------------------------------------------------------
88; Returns L-CHS parameters for drive and total hard disk count.
89;
90; AH8h_GetDriveParameters
91; Parameters:
92; DS:DI: Ptr to DPT (in RAMVARS segment)
93; Returns:
94; CH: Maximum cylinder number, bits 7...0
95; CL: Bits 7...6: Cylinder number bits 9...8
96; Bits 5...0: Maximum sector number (1...63)
97; DH: Maximum head number (0...254)
98; Corrupts registers:
99; AX, BX
100;--------------------------------------------------------------------
101AH8h_GetDriveParameters:
102 call AccessDPT_GetLCHStoAXBLBH
103%ifdef RESERVE_DIAGNOSTIC_CYLINDER
104 dec ax
105%endif
106 MIN_U ax, MAX_LCHS_CYLINDERS
107 ; Fall to .PackReturnValues
108
109;--------------------------------------------------------------------
110; Packs L-CHS values to INT 13h, AH=08h return values.
111;
112; .PackReturnValues
113; Parameters:
114; AX: Number of L-CHS cylinders available (1...1024)
115; BL: Number of L-CHS heads (1...255)
116; BH: Number of L-CHS sectors per track (1...63)
117; DS: RAMVARS segment
118; Returns:
119; CH: Maximum cylinder number, bits 7...0
120; CL: Bits 7...6: Cylinder number bits 9...8
121; Bits 5...0: Maximum sector number (1...63)
122; DH: Maximum head number (0...254)
123; Corrupts registers:
124; AX, BX
125;--------------------------------------------------------------------
126.PackReturnValues:
127 dec ax ; AX = Number of last cylinder
128 dec bx ; BL = Number of last head
129 xchg cx, ax
130 xchg cl, ch ; CH = Last cylinder bits 0...7
131 eROR_IM cl, 2 ; CL bits 6...7 = Last cylinder bits 8...9
132 or cl, bh ; CL bits 0...5 = Sectors per track
133 mov dh, bl ; DH = Maximum head number
134
135%ifdef MODULE_SERIAL_FLOPPY
136 mov bl, [di+DPT.bFlagsHigh]
137%ifndef CHECK_FOR_UNUSED_ENTRYPOINTS ; not sure why this is needed for preprocessor-only
138 eSHR_IM bl, FLGH_DPT_SERIAL_FLOPPY_TYPE_FIELD_POSITION
139%endif
140%endif
141 ret
142
143%ifdef MODULE_SERIAL_FLOPPY
144;
145; Floppy Disk Parameter Table. There is no way to specify more than one of these
146; for any given system, so no way to make this drive or media specific.
147; So we return fixed values out of the ROM for callers who might be expecting this information.
148;
149; On AT systems, we return the information for a 1.44 MB disk,
150; and on XT systems, we return the information for a 360 KB disk.
151;
152AH8h_FloppyDPT:
153%ifdef USE_AT
154 db 0ah << 4 | 0fh ; Offset 0: Drive timings, 1.44MB values
155%else
156 db 0dh << 4 | 0fh ; Offset 0: Drive timings, 360KB values
157%endif
158
159 db 1h << 1 | 0 ; Offset 1: Typical values of 1 for head load time
160 ; DMA used (although it actually is not, but is more restrictive)
161 db 25h ; Offset 2: Inactivity motor turn-off delay,
162 ; Typical value of 25h for 2 second delay
163 db 02h ; Offset 3: Sector size, always 512
164
165%ifdef USE_AT
166 db 12h ; Offset 4: Sectors per track, 1.44MB value
167 db 1bh ; Offset 5: Sector gap, 1.44MB value
168%else
169 db 09h ; Offset 4: Sectors per track, 360KB value
170 db 2ah ; Offset 5: Sector gap, 360KB value
171%endif
172
173 db 0ffh ; Offset 6: Data length
174
175%ifdef USE_AT
176 db 6ch ; Offset 7: Format gap length, 1.44MB value
177%else
178 db 50h ; Offset 7: Format gap length, 360KB value
179%endif
180
181 db 0f6h ; Offset 8: Fill byte for format
182 db 0fh ; Offset 9: Head setting time
183 db 08h ; Offset A: Wait for motor startup time
184
185%ifdef USE_AT
186 db 79 ; Offset B: Maximum track number, 1.44MB value
187 db 0 ; Offset C: Data transfer rate, 1.44MB value
188 db 4 ; Offset D: Diskette CMOS drive type, 1.44MB value
189%else
190 db 39 ; Offset B: Maximum track number, 360KB value
191 db 80h ; Offset C: Data transfer rate, 360KB value
192 db 1 ; Offset D: Diskette CMOS drive type, 360KB value
193%endif
194%endif
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