source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Boot/BootMenu.asm@ 144

Last change on this file since 144 was 130, checked in by Tomi Tilli, 14 years ago

Changes to XTIDE Universal BIOS:

  • Boot menu finally works but timeout and drive numbers not yet implemented.
File size: 5.8 KB
RevLine 
[88]1; Project name : XTIDE Universal BIOS
[3]2; Description : Displays Boot Menu.
3
4; Section containing code
5SECTION .text
6
7;--------------------------------------------------------------------
8; Displays Boot Menu and returns Drive or Function number.
9;
10; BootMenu_DisplayAndReturnSelection
11; Parameters:
12; DS: RAMVARS segment
13; Returns:
[95]14; DX: Untranslated drive number to be used for booting
[3]15; Corrupts registers:
16; All General Purpose Registers
17;--------------------------------------------------------------------
18ALIGN JUMP_ALIGN
19BootMenu_DisplayAndReturnSelection:
20 call DriveXlate_Reset
21 call BootMenuPrint_TheBottomOfScreen
22 call BootMenu_Enter ; Get selected menuitem index to CX
23 call BootMenuPrint_ClearScreen
[88]24 cmp cx, BYTE NO_ITEM_SELECTED
[95]25 je SHORT BootMenu_DisplayAndReturnSelection ; Clear screen and display menu
[130]26 ; Fall to BootMenu_GetDriveToDXforMenuitemInCX
[88]27
[128]28;--------------------------------------------------------------------
[130]29; BootMenu_GetDriveToDXforMenuitemInCX
[128]30; Parameters:
31; CX: Index of menuitem selected from Boot Menu
32; DS: RAMVARS segment
33; Returns:
34; DX: Drive number to be used for booting
35; Corrupts registers:
36; CX
37;--------------------------------------------------------------------
38ALIGN JUMP_ALIGN
[130]39BootMenu_GetDriveToDXforMenuitemInCX:
[128]40 mov dx, cx ; Copy menuitem index to DX
41 call FloppyDrive_GetCountToCX
42 cmp dx, cx ; Floppy drive?
43 jb SHORT .ReturnFloppyDriveInDX
44 sub dx, cx ; Remove floppy drives from index
45 or dl, 80h
46.ReturnFloppyDriveInDX:
47 ret
[88]48
[128]49
[88]50;--------------------------------------------------------------------
51; Enters Boot Menu or submenu.
52;
53; BootMenu_Enter
54; Parameters:
55; Nothing
56; Returns:
57; CX: Index of selected item or NO_ITEM_SELECTED
58; Corrupts registers:
[127]59; AX, BX, DI
[88]60;--------------------------------------------------------------------
[3]61ALIGN JUMP_ALIGN
[88]62BootMenu_Enter:
63 mov bx, BootMenuEvent_Handler
64 CALL_MENU_LIBRARY DisplayWithHandlerInBXandUserDataInDXAX
65 xchg cx, ax
[3]66 ret
67
68
69;--------------------------------------------------------------------
70; Returns number of menuitems in Boot Menu.
71;
[124]72; BootMenu_GetMenuitemCountToAX
[3]73; Parameters:
74; DS: RAMVARS segment
75; Returns:
[124]76; AX: Number of boot menu items
[3]77; Corrupts registers:
[124]78; CX
[3]79;--------------------------------------------------------------------
80ALIGN JUMP_ALIGN
[124]81BootMenu_GetMenuitemCountToAX:
[32]82 call RamVars_GetHardDiskCountFromBDAtoCX
83 xchg ax, cx
[124]84 call FloppyDrive_GetCountToCX
[3]85 add ax, cx
86 ret
87
88
89;--------------------------------------------------------------------
[124]90; BootMenu_GetHeightToAHwithItemCountInAL
[3]91; Parameters:
[124]92; AL: Number of menuitems
[3]93; Returns:
[88]94; AH: Boot menu height
[3]95; Corrupts registers:
[124]96; AL, CX, DI
[3]97;--------------------------------------------------------------------
98ALIGN JUMP_ALIGN
[124]99BootMenu_GetHeightToAHwithItemCountInAL:
[128]100 add al, BOOT_MENU_HEIGHT_WITHOUT_ITEMS
[124]101 xchg cx, ax
[88]102 CALL_DISPLAY_LIBRARY GetColumnsToALandRowsToAH
[124]103 sub ah, MENU_SCREEN_BOTTOM_LINES*2 ; Leave space for bottom info
[88]104 MIN_U ah, cl
[3]105 ret
106
107
108;--------------------------------------------------------------------
[130]109; BootMenu_GetMenuitemToAXforAsciiHotkeyInAL
[3]110; Parameters:
[130]111; AL: ASCII hotkey
[3]112; Returns:
[130]113; AX: Menuitem index
[3]114; Corrupts registers:
[130]115; CX
[3]116;--------------------------------------------------------------------
117ALIGN JUMP_ALIGN
[130]118BootMenu_GetMenuitemToAXforAsciiHotkeyInAL:
119 call Char_ALtoUpperCaseLetter
[92]120 call BootMenu_GetLetterForFirstHardDiskToCL
[130]121 xor ah, ah
[3]122 cmp al, cl ; Letter is for Hard Disk?
123 jae SHORT .StartFromHardDiskLetter
124 sub al, 'A' ; Letter to Floppy Drive menuitem
125 ret
126ALIGN JUMP_ALIGN
127.StartFromHardDiskLetter:
128 sub al, cl ; Hard Disk index
[124]129 call FloppyDrive_GetCountToCX
[130]130 add ax, cx ; Menuitem index
[3]131 ret
132
[128]133
[3]134;--------------------------------------------------------------------
135; Returns letter for first hard disk. Usually it will be 'c' but it
136; can be higher if more than two floppy drives are found.
137;
[92]138; BootMenu_GetLetterForFirstHardDiskToCL
[3]139; Parameters:
140; Nothing
141; Returns:
142; CL: Upper case letter for first hard disk
143; Corrupts registers:
144; CH
145;--------------------------------------------------------------------
146ALIGN JUMP_ALIGN
[92]147BootMenu_GetLetterForFirstHardDiskToCL:
[124]148 call FloppyDrive_GetCountToCX
[3]149 add cl, 'A'
150 MAX_U cl, 'C'
151 ret
152
153
154;--------------------------------------------------------------------
[124]155; BootMenu_GetMenuitemToDXforDriveInDL
[3]156; Parameters:
157; DL: Drive number
158; Returns:
[124]159; DX: Menuitem index (assuming drive is available)
[3]160; Corrupts registers:
[124]161; Nothing
[3]162;--------------------------------------------------------------------
163ALIGN JUMP_ALIGN
[124]164BootMenu_GetMenuitemToDXforDriveInDL:
165 xor dh, dh ; Drive number now in DX
[128]166 test dl, dl
167 jns SHORT .ReturnItemIndexInDX ; Return if floppy drive (HD bit not set)
[124]168 call FloppyDrive_GetCountToCX
[127]169 and dl, ~80h ; Clear HD bit
[124]170 add dx, cx
171.ReturnItemIndexInDX:
[3]172 ret
173
174
175;--------------------------------------------------------------------
176; Checks is drive number valid for this system.
177;
178; BootMenu_IsDriveInSystem
179; Parameters:
180; DL: Drive number
181; DS: RAMVARS segment
182; Returns:
[28]183; CF: Set if drive number is valid
[3]184; Clear if drive is not present in system
185; Corrupts registers:
[28]186; AX, CX
[3]187;--------------------------------------------------------------------
188ALIGN JUMP_ALIGN
189BootMenu_IsDriveInSystem:
[128]190 test dl, dl ; Floppy drive?
[130]191 jns SHORT .IsFloppyDriveInSystem
[32]192 call RamVars_GetHardDiskCountFromBDAtoCX ; Hard Disk count to CX
193 or cl, 80h ; Set Hard Disk bit to CX
[28]194 jmp SHORT .CompareDriveNumberToDriveCount
[130]195.IsFloppyDriveInSystem:
[124]196 call FloppyDrive_GetCountToCX
[28]197.CompareDriveNumberToDriveCount:
[124]198 cmp dl, cl ; Set CF when DL is smaller
[3]199 ret
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