source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH8h_HParams.asm@ 261

Last change on this file since 261 was 261, checked in by gregli@…, 13 years ago

Basic maintenance to enable the unused code check to work again, no real code change. Verified no unused code.
File size: 5.8 KB
Line 
1; Project name : XTIDE Universal BIOS
2; Description : Int 13h function AH=8h, Read Disk Drive Parameters.
3
4; Section containing code
5SECTION .text
6
7;--------------------------------------------------------------------
8; Int 13h function AH=8h, Read Disk Drive Parameters.
9;
10; AH8h_HandlerForReadDiskDriveParameters
11; Parameters:
12; DL: Translated Drive number
13; DS:DI: Ptr to DPT (in RAMVARS segment)
14; SS:BP: Ptr to IDEPACK
15; Returns with INTPACK:
16; BL: Drive Type (for floppies only)
17; CH: Maximum cylinder number, bits 7...0
18; CL: Bits 7...6: Cylinder number bits 9...8
19; Bits 5...0: Maximum sector number (1...63)
20; DH: Maximum head number (0...255)
21; DL: Number of drives
22; ES:DI: Floppy DPT (for floppies only)
23; AH: Int 13h/40h floppy return status
24; CF: 0 if successfull, 1 if error
25;--------------------------------------------------------------------
26AH8h_HandlerForReadDiskDriveParameters:
27
28 call RamVars_IsDriveHandledByThisBIOS
29 jnc SHORT .OurDrive
30
31 call Int13h_CallPreviousInt13hHandler
32 jnc SHORT .MidGame
33 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
34
35.OurDrive:
36 call AH8h_GetDriveParameters
37
38%ifdef MODULE_SERIAL_FLOPPY
39 push cs ; setup registers if we are a floppy drive, in all cases
40 pop es ; if it is not a floppy drive, these values will not be put in INTPACK
41 mov di, AH8h_FloppyDPT
42%endif
43 ;; fall-through
44
45.MidGame:
46 call RamVars_GetCountOfKnownDrivesToAX ; assume hard disk for now, will discard if for floppies
47
48 test byte [bp+IDEPACK.intpack+INTPACK.dl], 080h
49 jnz .Done
50
51 mov [bp+IDEPACK.intpack+INTPACK.bl], bl
52
53 mov [bp+IDEPACK.intpack+INTPACK.es], es
54 mov [bp+IDEPACK.intpack+INTPACK.di], di
55
56 call FloppyDrive_GetCountToAX
57
58.Done:
59 mov ah, dh
60
61 mov [bp+IDEPACK.intpack+INTPACK.cx], cx
62 xchg [bp+IDEPACK.intpack+INTPACK.dx], ax ; recover DL for BDA last status byte determination
63
64 xor ah, ah
65%ifdef MODULE_SERIAL_FLOPPY
66 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH_ALHasDriveNumber
67%else
68 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
69%endif
70
71
72;--------------------------------------------------------------------
73; Returns L-CHS parameters for drive and total hard disk count.
74;
75; AH8h_GetDriveParameters
76; Parameters:
77; DS:DI: Ptr to DPT (in RAMVARS segment)
78; Returns:
79; CH: Maximum cylinder number, bits 7...0
80; CL: Bits 7...6: Cylinder number bits 9...8
81; Bits 5...0: Maximum sector number (1...63)
82; DH: Maximum head number (0...255)
83; Corrupts registers:
84; AX, BX
85;--------------------------------------------------------------------
86AH8h_GetDriveParameters:
87 call AccessDPT_GetLCHStoAXBLBH
88 ; Fall to .PackReturnValues
89
90;--------------------------------------------------------------------
91; Packs L-CHS values to INT 13h, AH=08h return values.
92;
93; .PackReturnValues
94; Parameters:
95; AX: Number of L-CHS cylinders available (1...1024)
96; BL: Number of L-CHS heads (1...256)
97; BH: Number of L-CHS sectors per track (1...63)
98; DS: RAMVARS segment
99; Returns:
100; CH: Maximum cylinder number, bits 7...0
101; CL: Bits 7...6: Cylinder number bits 9...8
102; Bits 5...0: Maximum sector number (1...63)
103; DH: Maximum head number (0...255)
104; Corrupts registers:
105; AX, BX
106;--------------------------------------------------------------------
107.PackReturnValues:
108 dec ax ; AX = Number of last cylinder
109 dec bx ; BL = Number of last head
110 xchg cx, ax
111 xchg cl, ch ; CH = Last cylinder bits 0...7
112 eROR_IM cl, 2 ; CL bits 6...7 = Last cylinder bits 8...9
113 or cl, bh ; CL bits 0...5 = Sectors per track
114 mov dh, bl ; DH = Maximum head number
115
116%ifdef MODULE_SERIAL_FLOPPY
117 mov bl,[di+DPT.bFlagsHigh]
118%ifndef CHECK_FOR_UNUSED_ENTRYPOINTS ; not sure why this is needed for preprocessor-only
119 eSHR_IM bl,FLGH_DPT_SERIAL_FLOPPY_TYPE_FIELD_POSITION
120%endif
121%endif
122 ret
123
124%ifdef MODULE_SERIAL_FLOPPY
125;
126; Floppy Disk Parameter Table. There is no way to specify more than one of these
127; for any given system, so no way to make this drive or media specific.
128; So we return fixed values out of the ROM for callers who might be expecting this information.
129;
130; On AT systems, we return the information for a 1.44 MB disk,
131; and on XT systems, we return the information for a 360 KB disk.
132;
133AH8h_FloppyDPT:
134%ifdef USE_AT
135 db 0ah << 4 | 0fh ; Offset 0: Drive timings, 1.44MB values
136%else
137 db 0dh << 4 | 0fh ; Offset 0: Drive timings, 360KB values
138%endif
139
140 db 1h << 1 | 0 ; Offset 1: Typical values of 1 for head load time
141 ; DMA used (although it actually is not, but is more restrctive)
142 db 25h ; Offset 2: Inactiviy motor turn-off delay,
143 ; Typical value of 25h for 2 second delay
144 db 02h ; Offset 3: Sector size, always 512
145
146%ifdef USE_AT
147 db 12h ; Offset 4: Sectors per track, 1.44MB value
148 db 1bh ; Offset 5: Sector gap, 1.44MB value
149%else
150 db 09h ; Offset 4: Sectors per track, 360KB value
151 db 2ah ; Offset 5: Sector gap, 360KB value
152%endif
153
154 db 0ffh ; Offset 6: Data length
155
156%ifdef USE_AT
157 db 6ch ; Offset 7: Format gap length, 1.44MB value
158%else
159 db 50h ; Offset 7: Format gap length, 360KB value
160%endif
161
162 db 0f6h ; Offset 8: Fill byte for format
163 db 0fh ; Offset 9: Head setting time
164 db 08h ; Offset A: Wait for motor startpu time
165
166%ifdef USE_AT
167 db 79 ; Offset B: Maximum track number, 1.44MB value
168 db 0 ; Offset C: Data transfer rate, 1.44MB value
169 db 4 ; Offset D: Diskette CMOS drive type, 1.44MB value
170%else
171 db 39 ; Offset B: Maximum track number, 360KB value
172 db 80h ; Offset C: Data transfer rate, 360KB value
173 db 1 ; Offset D: Diskette CMOS drive type, 360KB value
174%endif
175%endif
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