INT 0x10 - 0x00 - Set video mode

Request/Call:

reg	value	descr
AH	0x00
AL	mode	Video Mode (see below)

Return:

Nothing

Parameters information

	text / grph	text resolution	char box	pixel resolution	colors	display pages	screen addr	system
00h	T	40×25	8×8		16gray	8	B800	CGA,PCjr
	T	40×25	8×14		16gray	8	B800	EGA
	T	40×25	8×16		16	8	B800	MCGA
	T	40×25	9×16		16	8	B800	VGA
01h	T	40×25	8×8		16	8	B800	CGA,PCjr
	T	40×25	8×14		16	8	B800	EGA
	T	40×25	8×16		16	8	B800	MCGA
	T	40×25	9×16		16	8	B800	VGA
02h	T	80×25	8×8		16gray	4	B800	CGA,PCjr
	T	80×25	8×14		16gray	4/8	B800	EGA
	T	80×25	8×16		16	4/8	B800	MCGA
	T	80×25	9×16		16	4/8	B800	VGA
03h	T	80×25	8×8		16	4	B800	CGA,PCjr
	T	80×25	8×14		16	4/8	B800	EGA
	T	80×25	8×16		16	4/8	B800	MCGA
	T	80×25	9×16		16	4/8	B800	VGA
04h	G	40×25	8×8	320×200	4		B800	CGA,PCjr,EGA,MCGA,VGA
05h	G	40×25	8×8	320×200	4gray		B800	CGA,PCjr,EGA
	G	40×25	8×8	320×200	4		B800	MCGA,VGA
06h	G	80×25	8×8	640×200	2		B800	CGA,PCjr,EGA,MCGA,VGA
07h	T	80×25	9×14		mono	no page	B000	MDA,Hercules
	T	80×25	9×16		mono	8	B000	EGA, VGA
08h	G	20×25	8×8	160×200	16			PCjr, Tandy 1000
	T	132×25	8×8		16		B800	ATI EGA/VGA Wonder ₍₁₎
	T	132×25	8×8		mono		B000	ATI EGA/VGA Wonder ₍₁₎
	G	90×43	8×8	720×352	mono		B000	Hercules + MSHERC.COM
09h	G	40×25	8×8	320×200	16			PCjr
0Ah	G	80×25	8×8	640×200	4			PCjr, Tandy 1000
0Bh		reserved (used internally by EGA BIOS)
	G			640×200	16			Tandy 1000 SL/TL
0Ch		reserved (used internally by EGA BIOS)
0Dh	G	40×25	8×8	320×200	16	8	A000	EGA,VGA
0Eh	G	80×25	8×8	640×200	16	4	A000	EGA,VGA
0Fh	G	80×25	8×14	640×350	mono	2	A000	EGA,VGA
10h	G	80×25	8×14	640×350	4	2	A000	64k EGA
	G			640×350	16		A000	256k EGA,VGA
11h	G	80×30	8×16	640×480	mono		A000	VGA,MCGA,ATI EGA,ATI VIP
12h	G	80×30	8×16	640×480	16/256k		A000	VGA,ATI VIP
	G	80×30	8×16	640×480	16/64		A000	ATI EGA Wonder
	G			640×480	16			UltraVision+256K EGA
13h	G	40×25	8×8	320×200	256/256k		A000	VGA,MCGA,ATI VIP
14h	T	132×25	Nx16		16			XGA, IBM Enhanced VGA ₍₂₎
	G	80×25	8×8	640×200				Lava Chrome II EGA
	G			640×400	16			Tecmar VGA/AD
15h	G	80×25	8×14	640×350				Lava Chrome II EGA
16h	G	80×25	8×14	640×350				Lava Chrome II EGA
	G			800×600	16			Tecmar VGA/AD
17h	G	80×34	8×14	640×480				Lava Chrome II EGA
	T	132×25						Tecmar VGA/AD
18h	T	132×44	8×8		mono			Tseng Labs EVA
	T	132×44	8×8		16/256	2	B000	Tseng ET4000 chipset
	G	80×34	8×14	640×480				Lava Chrome II EGA
	G		1	024×768	16			Tecmar VGA/AD
19h	T	132×25	8×14		mono			Tseng Labs EVA
	T	132×25	8×14		16/256	4	B000	Tseng ET4000 chipset
1Ah	T	132×28	8×13		mono			Tseng Labs EVA
	T	132×28	8×13		16/256	4	B000	Tseng ET4000 chipset
	G			640×350	256			Tecmar VGA/AD
1Bh	G			640×400	256			Tecmar VGA/AD
1Ch	G			640×480	256			Tecmar VGA/AD
1Dh	G			800×600	256			Tecmar VGA/AD
20h	G			240×128			B000	HP 95LX
21h	T	132×60			16	2	B800	Tseng ET4000 chipset
	G	80×43	8×8	720×348	mono		B000	DESQview 2.x+Hercules ₍₃₎
22h	T	132×44	8×8					Tseng Labs EVA
	T	132×44	8×8		16/256	2	B800	Tseng ET4000 chipset
	T	132×44	8×8					Ahead Systems EGA2001
	T	132×44	8×8		16	2	B800	Ahead B
	T	132×44			16			Orchid Prodesigner VGA
	T	132×43						Allstar Peacock (VGA)
	G	80×43	8×8	720×348	mono		B800	DESQview 2.x+Hercules ₍₃₎
23h	T	132×25	6×14					Tseng Labs EVA
	T	132×25	8×14		16/256	4	B800	Tseng ET4000 chipset
	T	132×25	8×14					Ahead Systems EGA2001
	T	132×25	8×14		16	4	B800	Ahead B
	T	132×25	8×8		16		B800	ATI EGA Wonder,ATI VIP
	T	132×28						Allstar Peacock (VGA)
	T	132×28			16			Orchid Prodesigner VGA
24h	T	132×28	6×13					Tseng Labs EVA
	T	132×28	8×13		16/256	4	B800	Tseng ET4000 chipset
	T	132×28	8×12		16	1	B800	Ahead B
	T	132×25						Allstar Peacock (VGA)
	T	132×25			16			Orchid Prodesigner VGA
25h	G	80×60	8×8	640×480				Tseng Labs EVA
	G	80×60	8×8	640×480	16/256	1	A000	Tseng ET4000 chipset
	G			640×480	16			VEGA VGA
	G	80×60	8×8	640×480	16		A000	Orchid Prodesigner VGA
	G	80×60	8×8	640×480	16	1	A000	Ahead B (same as 26h)
	G			640×480	16			NEC GB-1
26h	T	80×60	8×8					Tseng Labs EVA
	T	80×60	8×8		16/256	2	B800	Tseng ET4000 chipset
	T	80×60						Allstar Peacock (VGA)
	T	80×60			16			Orchid ProDesigner VGA
	G	80×60	8×8	640×480				Ahead Systems EGA2001
	G	80×60	8×8	640×480	16	1	A000	Ahead B (same as 25h)
27h	T	132×25	8×8		mono		B000	ATI EGA Wonder,ATI VIP
	G			720×512	16			VEGA VGA
	G			720×512	16			Genoa
28h	T	???x???						VEGA VGA
29h	G			800×600	16			VEGA VGA
	G	100×37	8×16	800×600	16		A000	Orchid
	G			800×600	16		A000	STB,Genoa,Sigma
	G			800×600	16			Allstar Peacock (VGA)
	G	100×37	8×16	800×600	16/256	1	A000	Tseng ET3000/4000 chipset
	G			800×600	???			EIZO MDB10
2Ah	T	100×40						Allstar Peacock (VGA)
	T	100×40	8×16		16			Orchid Prodesigner VGA
	T	100×40	8×15		16/256	4	B800	Tseng ET4000 chipset
2Dh	G			640×350	256			VEGA VGA
	G			640×350	256/256k		A000	Orchid, Genoa, STB
	G	80×25	8×14	640×350	256/256k	1	A000	Tseng ET3000/4000 chipset
2Eh	G			640×480	256			VEGA VGA
	G	80×30	8×16	640×480	256/256k		A000	Orchid
	G			640×480	256/256k		A000	STB,Genoa,Sigma
	G	80×30	8×16	640×480	256/256k	1	A000	Tseng ET3000/4000 chipset
2Fh	T	160×50	8×8 1	280×400	16	4	B800	Ahead B (Wizard/3270)
	G			720×512	256			VEGA VGA
	G			720×512	256			Genoa
	G	80×25	8×16	640×400	256/256k	1	A000	Tseng ET4000 chipset
30h	G			800×600	256			VEGA VGA
	G	100×37	8×16	800×600	256/256k		A000	Orchid
	G			800×600	256/256k		A000	STB,Genoa,Sigma
	G			720×350	2			3270 PC
	G			800×600	256			Cardinal
	G			???x???			B800	AT&T 6300
	G	100×37	8×16	800×600	256/256k	1	A000	Tseng ET3000/4000 chipset
32h	T	80×34	8×10		16	4	B800	Ahead B (Wizard/3270)
33h	T	132×44	8×8		16		B800	ATI EGA Wonder,ATI VIP
	T	80×34	8×8		16	4	B800	Ahead B (Wizard/3270)
34h	T	80×66	8×8		16	4	B800	Ahead B (Wizard/3270)
36h	G			960×720	16			VEGA VGA
	G			960×720	16			STB
	G			960×720	16			Tseng ET3000 only
37h	G		1	024×768	16			VEGA VGA
	G	128×48	8×16 1	024×768	16		A000	Orchid
	G		1	024×768	16		A000	STB,Genoa,Sigma
	G		1	024×768	16			Definicon
	G	128×48	8×16 1	024×768	16	1	A000	Tseng ET3000/4000
	T	132×44	8×8		mono		B800	ATI EGA Wonder,ATI VIP
38h	G		1	024×768	256			STB VGA/EM-16 Plus (1MB)
	G	128×48	8×16 1	024×768	256/256k	1	A000	Tseng ET4000 chipset
	G		1	024×768	256			Orchid ProDesigner II
3Dh	G		1	280×1024	16			Definicon
	G	128×64	8×16 1	280×1024	16	1	A000	Tseng ET4000 BIOS v3.00 ₍₆₎
3Eh	G		1	280×961	16			Definicon
40h	G	80×25	8×16	640×400	2	1	B800	AT&T 6300, AT&T VDC600
	G	80×25	8×16	640×400	2	1	B800	Compaq Portable
	T	80×43						VEGA VGA, Tecmar VGA/AD
	T	80×43						Video7 V-RAM VGA
	T	80×43						Tatung VGA
	T	100×30			16			MORSE VGA
41h	G			640×200	16	1		AT&T 6300
	T	132×25						VEGA VGA
	T	132×25						Tatung VGA
	T	132×25						Video7 V-RAM VGA
	T	100×50			16			MORSE VGA
42h	G	80×25	8×16	640×400	16			AT&T 6300, AT&T VDC600
	T	132×43						VEGA VGA
	T	132×43						Tatung VGA
	T	132×43						Video7 V-RAM VGA
	T	80×34	9×10		4	4	B800	Ahead B (Wizard/3270)
	T	100×60			16			MORSE VGA
43h	G	640×200 of 640×400 viewport						AT&T 6300 (unsupported)
	T	80×60						VEGA VGA
	T	80×60						Tatung VGA
	T	80×60						Video7 V-RAM VGA
	T	80×45	9×8		4	4	B800	Ahead B (Wizard/3270)
	T	100×75			16			MORSE VGA
44h		disable VDC and DEB output						AT&T 6300
	T	100×60						VEGA VGA
	T	100×60						Tatung VGA
	T	100×60						Video7 V-RAM VGA
45h	T	132×28						Tatung VGA
	T	132×28						Video7 V-RAM VGA
46h	G	100×40	8×15	800×600	2			AT&T VDC600
47h	G	100×37	8×16	800×600	16			AT&T VDC600
48h	G	80×50	8×8	640×400	2		B800	AT&T 6300, AT&T VDC600
49h	G	80×30	8×16	640×480				Lava Chrome II EGA
4Dh	T	120×25						VEGA VGA
4Eh	T	120×43						VEGA VGA
4Fh	T	132×25						VEGA VGA
	T	132×60						some Oak Tech VGA
50h	G	80×30	8×16	640×480	16			Paradise EGA-480
	T	80×30	8×16		16/256k		B800	Trident TVGA 8800/8900
	T	80×34						Lava Chrome II EGA
	T	80×43			mono			VEGA VGA
	G			640×480	mono???			Taxan 565 EGA
	T	132×25	9×14		mono			Ahead Systems EGA2001
	T	132×25	9×14		4	4	B800	Ahead B
	T	132×25	8×14		16	8	B800	OAK Technologies VGA-16
	T	132×30			16			MORSE VGA
51h	T	80×30	8×16					Paradise EGA-480
	T	80×30						Lava Chrome II EGA
	G	80×34	8×14	640×480	16			ATI EGA Wonder
	T	80×43	8×11		16/256k		B800	Trident TVGA 8800/8900
	T	132×25			mono			VEGA VGA
	T	132×43	8×8		16	5	B800	OAK Technologies VGA-16
	T	132×28	9×12		4	4	B800	Ahead B
	T	132×50			16			MORSE VGA
52h	T	80×60						Lava Chrome II EGA
	T	80×60	8×8		16/256k		B800	Trident TVGA 8800/8900
	G	94×29	8×14	752×410	16			ATI EGA Wonder
	G	100×75	8×8	800×600	16	1	A000	OAK Technologies VGA-16
	T	132×43			mono			VEGA VGA
	T	132×44	9×8		mono			Ahead Systems EGA2001
	T	132×44	9×8		4	2	B800	Ahead B
	T	132×60			16			MORSE VGA
53h	G	100×40	8×14	800×560	16			ATI EGA Wonder,ATI VIP
	G			640×480	256			Oak VGA
	T	132×25	8×14		16/256k		B800	Trident TVGA 8800/8900
	T	132×43						Lava Chrome II EGA
	T	80×60			16			MORSE VGA
	G							AX PC
54h	G	100×42	8×14	800×600	16		A000	ATI EGA Wonder, VGA Wonder
	G			800×600	256			Oak VGA
	T	132×25						Lava Chrome II EGA
	T	132×30	8×16		16/256k		B800	Trident TVGA 8800/8900
	T	132×43	8×8					Paradise EGA-480
	T	132×43	7×9		16/256k		B800	Paradise VGA
	T	132×43	8×9		16/256k		B800	Paradise VGA on multisync
	T	132×43						Taxan 565 EGA
	T	132×43						AST VGA Plus
	T	132×43						Hewlett-Packard D1180A
	T	132×43	7×9		16			AT&T VDC600
55h	T	80×66	8×8		16/256k		A000	ATI VIP
	T	132×25	8×14					Paradise EGA-480
	T	132×25	7×16		16/256k		B800	Paradise VGA
	T	132×25	8×16		16/256k		B800	Paradise VGA on multisync
	T	132×25						Taxan 565 EGA
	T	132×25						AST VGA Plus
	T	132×25						Hewlett-Packard D1180A
	T	132×25	7×16		16			AT&T VDC600
	T	132×43	8×11		16/256k		B800	Trident TVGA 8800/8900
	G	94×29	8×14	752×410				Lava Chrome II EGA
	G	128×48	8×16 1	024×768	16/256k		A000	ATI VGA Wonder v4+ ₍₄₎
	G		1	024×768	16/256h			ATI VGA Wonder Plus
56h	T	132×43	8×8		3???	2	B000	NSI Smart EGA+
	T	132×43	7×9		4		B000	Paradise VGA
	T	132×43	8×9		4		B000	Paradise VGA on multisync
	T	132×43			mono			Taxan 565 EGA
	T	132×43	7×9		2			AT&T VDC600
	T	132×60	8×8		16/256k		B800	Trident TVGA 8800/8900
	G		1	024×768	16			Oak VGA
57h	T	132×25	8×14		3???	4	B000	NSI Smart EGA+
	T	132×25	7×16		4		B000	Paradise VGA
	T	132×25	8×16		4		B000	Paradise VGA on multisync
	T	132×25			mono			Taxan 565 EGA
	T	132×25	7×16		2			AT&T VDC600
	T	132×25	9×14		16/256k		B800	Trident TVGA 8800/8900
58h	G	100×75	8×8	800×600	16/256k		A000	Paradise VGA
	G	100×75	8×8	800×600	16			AT&T VDC600
	T	80×33	8×14		16		B800	ATI EGA Wonder,ATI VIP
	G			800×600	16			AST VGA Plus, Compaq VGA
	G			800×600	16			Dell VGA
	G			800×600	16			Hewlett-Packard D1180A
	G			800×600	???			ELT VGA PLUS 16
	T	132×30	9×16		16/256k		B800	Trident TVGA 8800/8900
59h	G	100×75	8×8	800×600	2		A000	Paradise VGA
	G	100×75	8×8	800×600	2			AT&T VDC600
	T	80×66	8×8		16/256k		A000	ATI VIP
	G			800×600	2			AST VGA Plus, Compaq VGA
	G			800×600	2			Dell VGA
	G			800×600	2			Hewlett-Packard D1180A
	T	132×43	9×11		16/256k		B800	Trident TVGA 8800/8900
5Ah	T	132×60	9×8		16/256k		B800	Trident TVGA 8800/8900
5Bh	G			800×600	16			Maxxon, SEFCO TVGA, Imtec
	G			640×350	256			Genoa 6400
	T	80×30	8×16				B800	ATI VGA Wonder (undoc)
	G	100×75	8×8	800×600	16/256k		A000	Trident TVGA 8800, 8900
	G			800×600	???			Vobis MVGA
5Ch	G			640×400	256			Logix, ATI Prism Elite
	G			640×400	256			Maxxon, SEFCO TVGA, Imtec
	G	80×25	8×16	640×400	256/256	k	A000	Zymos Poach, Hi Res 512
	G	80×25	8×16	640×400	256/256	k	A000	Trident TVGA 8800/8900
	G			640×480	256			Genoa 6400
5Dh	G			640×480	256			Logix, ATI Prism Elite
	G			640×480	256			Maxxon, SEFCO TVGA, Imtec
	G	80×30	8×16	640×480	256/256	k	A000	Zymos Poach, Hi Res 512
	G	80×30	8×16	640×480	256/256	k	A000	Trident TVGA 8800 (512K)
5Eh	G			640×400	256			Paradise VGA,VEGA VGA
	G			640×400	256			AST VGA Plus
	G			640×400	256			Compaq VGA, Dell VGA
	G	80×25	8×16	640×400	256			AT&T VDC600
	G			800×600	16			Logix, ATI Prism Elite
	G			800×600	256			Genoa 6400
	G	100×75	8×8	800×600	256/256	k	A000	Zymos Poach, Trident 8900
	G	100×75	8×8	800×600	256/256	k	A000	Hi Res 512
5Fh	G			640×480	256			Paradise VGA
	G			640×480	256			AST VGA Plus
	G			640×480	256			Compaq VGA, Dell VGA
	G			640×480	256			Hewlett-Packard D1180A
	G	80×30	8×16	640×480	256			AT&T VDC600 (512K)
	G		1	024×768	16			Logix, ATI Prism Elite
	G		1	024×768	16			Maxxon, Genoa 6400, Imtec
	G	128×48	8×16 1	024×768	16/256	k	A000	Zymos Poach, Hi Res 512
	G	128×48	8×16 1	024×768	16/256	k	A000	Trident TVGA 88/8900 512K
60h	G	80x???		???x400				Corona/Cordata BIOS 4.10+
	G			752×410				VEGA VGA
	G			752×410	16			Tatung VGA
	G			752×410	16			Video7 V-RAM VGA
	G	80×25	8×16	640×400	256	1	A000	Ahead A, Ahead B
	G	128×48	8×16 1	024×768	4/256	k	A000	Trident TVGA 8900
	T	132×25	8×14		16/64	8	B800	Quadram Ultra VGA
61h	G			???x400				Corona/Cordata BIOS 4.10+
	G			720×540				VEGA VGA
	G			720×540	16			Tatung VGA
	G			720×540	16			Video7 V-RAM VGA
	G	80×25	8×16	640×400	256		A000	ATI VGA Wonder,VGA Wonder+
	G	80×30	8×16	640×480	256	1	A000	Ahead A, Ahead B (512K)
	G	96×64	8×16	768×1024	16/256	k	A000	Trident TVGA 88/8900 512K
	T	132×29	8×12		16/64	8	B800	Quadram Ultra VGA
62h	G			800×600				VEGA VGA
	G			800×600	16			Tatung VGA
	G			800×600	16			Video7 V-RAM VGA
	G	80×30	8×16	640×480	256		A000	ATI VGA Wonder,VGA Wonder+
	G	100×75	8×8	800×600	256	1	A000	Ahead A, Ahead B (512K)
	G	128×48	8×16 1	024×768	256/256	k	A000	Trident TVGA 8900, Zymos
	T	132×32	8×11		16/64	6	B800	Quadram Ultra VGA
63h	G		1	024×768	2			Video7 V-RAM VGA
	G	100×42	8×14	800×600	256		A000	ATI VGA Wonder,VGA Wonder+
	G	128×48	7×16 1	024×768	256	1	A000	Ahead B (1MB)
	T	132×44	8×8		16/64	5	B800	Quadram Ultra VGA
	G			720×540	16			MORSE VGA
64h	G		1	024×768	4			Video7 V-RAM VGA
	G	128×48	8×16 1	024×768	256		A000	ATI VGA Wonder Plus
	G			800×600	16			MORSE VGA
	G			800×600	???			SAMPO-Mira VGA
65h	G		1	024×768	16			Video7 V-RAM VGA
	G	128×48	8×16 1	024×768	16		A000	ATI VGA Wonder
66h	G			640×400	256			Tatung VGA
	G			640×400	256			Video7 V-RAM VGA
67h	G			640×480	256			Video7 V-RAM VGA
	G	128×48	8×16 1	024×768	4		A000	ATI VGA Wonder
69h	G			720×540	256			Video7 V-RAM VGA
6Ah	G			800×600	16		A000	VESA standard interface
	G			800×600	16			Genoa 6400
	G			800×600	16		A000	Ahead A
	G	100×75	8×8	800×600	16	1	A000	Ahead B (VESA) (see 71h)
	G			800×600	16			Zymos Poach, Hi Res 512
	G			800×600	16			Epson LT-386SX in CRT Mode
	G			800×600	16			Compuadd 316SL in CRT Mode
	G	100×42	8×14	800×600			A000	ATI VGA Wonder (undoc)
70h	G			800×600	16			C&T chipset, Cardinal
	G	90×28	8×14	720×392	16	1	A000	Ahead B
	T	40×25	8×8		16	8	B800	Quadram (CGA double scan)
		extended mode set (see AX=0070h)						Everex Micro Enhancer EGA
71h	G	100×35	8×16	800×600	16of64		A000	NSI Smart EGA+
	G			960×720	16			C&T chipset, Cardinal
	G	100×75	8×8	800×600	16	1	A000	Ahead B (same as 6Ah)
	T	80×25	8×8		16	8	B800	Quadram (CGA double scan)
72h	G		1	024×768	16			C&T chipset, Cardinal
	T	80×60	8×8		16		B800	Quadram Ultra VGA
	G			640×480	32768		A000	ATI
73h	G	80×60	8×8	640×480	16???		A000	Quadram Ultra VGA
74h	G			640×400	2		B800	Toshiba 3100 AT&T mode
	G	128×48	8×16 1	024×768	16	1	A000	Ahead A, Ahead B (512K)
	T	80×66	8×8		16		B800	Quadram Ultra VGA
75h	G	128×48	8×16 1	024×768	4	1	A000	Ahead B
	G	80×66		640×528	16???		A000	Quadram Ultra VGA
	G			640×528	16			Geno Super EGA Hirez+
76h	G	128×48	8×16 1	024×768	2	1	A000	Ahead B
	T	94×29	8×14		16		B800	Quadram Ultra VGA
77h	G	94×29		752×410	16???		A000	Quadram Ultra VGA
	G			752×410	16			Genoa Super EGA Hirez+
78h	G			640×400	256			STB VGA/EM-16 Plus
	G			640×400	256			Cardinal, C&T chipset
	T	100×75	8×8		16		B800	Quadram Ultra VGA
79h	G			640×480	256			Cardinal, C&T chipset
	G	100×75		800×600	16???		A000	Quadram Ultra VGA
	G			800×600	16			Genoa Super EGA Hirez+
7Ah	G			720×540	256			C&T chipset, Cardinal
	T	114×60	8×8		16		B800	Quadram Ultra VGA
7Bh	G			800×600	256			C&T chipset, Cardinal
	G	114×60		912×480	16???		A000	Quadram Ultra VGA
	G			912×480	16			Genoa Super EGA Hirez+
7Ch	G			512×512	16			Genoa
7Dh	G			512×512	256			Genoa
7Eh		special mode set (see AX=007Eh)						Paradise VGA, AT&T VDC600
7Fh		special function set (see AX=007Fh)						Paradise VGA, AT&T VDC600
82h	T	80×25			B&W			AT&T VDC overlay mode ₍₅₎
83h	T	80×25						AT&T VDC overlay mode ₍₅₎
86h	G			640×200	B&W			AT&T VDC overlay mode ₍₅₎
88h	G	90×43	8×8	720×352	mono		B000	Hercules + MSHERC.COM
8xh								EGA, MCGA or VGA ignore bit 7, see below
9xh								EGA, MCGA or VGA ignore bit 7, see below
C0h	G			640×400	2/prog	pallet		AT&T VDC overlay mode ₍₅₎
C4h		disable output						AT&T VDC overlay mode ₍₅₎
D0h	G			640×400	2		B800	DEC VAXmate AT&T mode

if AL bit 7=1, prevents EGA,MCGA & VGA from clearing display
function updates byte at 40:49; bit 7 of byte 40:87 (EGA/VGA Display Data Area) is set to the value of AL bit 7

(1) ATI

for ATI EGA Wonder, mode 08h is only valid if SMS.COM is loaded resident.

SMS maps mode 08h to mode 27h if the byte at location 0040:0063 is 0B4h, otherwise to mode 23h, thus selecting the appropriate (monochrome or color) 132×25 character mode.

for ATI VGA Wonder, mode 08h is the same, and only valid if VCONFIG loaded resident

(2) XGA

early XGA boards support 132-column text but do not have this BIOS mode

(3) DESQview

DESQview intercepts calls to change into these two modes (21h is page 0, 22h is page 1) even if there is no Hercules graphics board installed

[4] ATI BIOS

ATI Bios v4-1.00 has a text-scrolling bug in this mode

(5) AT&T & VDC overlay

for AT&T VDC overlay modes, BL contains the DEB mode, which may be 06h, 40h, or 44h

(6)Tseng

BIOS text support is broken in this undocumented mode; scrolling moves only about 1/3 of the screen (and does even that portion incorrectly), while screen clears only clear about 3/4.

2023/01/10 15:53 · frater

Detecting Graphics Card

Ahead Adapter

the installation check for Ahead adapters is the signature “AHEAD” at C000h:0025h

ATI

the installation check for ATI adapters is the signature “761295520” at C000h:0031h;

the byte at C000h:0043h indicates the chipset revision:

31h for 18800
32h for 18800-1
33h for 18800-2
34h for 18800-4
35h for 18800-5

the two bytes at C000h:0040h indicate the adapter type

“31” VGA Wonder
“32” EGA Wonder800+

Card accessories

the byte at C000h:0042h contains feature flags

bit 1: mouse port present
bit 4: programmable video clock

additionnal features

the byte at C000h:0044h contains additional feature flags if chipset byte > 30h

bit 0: 70 Hz non-interlaced display
bit 1: Korean (double-byte) characters
bit 2: 45 MHz memory clock rather than 40 MHz
bit 3: zero wait states
bit 4: paged ROMs
bit 6: no 8514/A monitor support
bit 7: HiColor DAC

Genoa Adapter

the installation check for Genoa video adapters is the signature 77h XXh 99h 66h at C000h:0037h, where XXh is

00h for Genoa 6200/6300
11h for Genoa 6400/6600
22h for Genoa 6100
33h for Genoa 5100/5200
55h for Genoa 5300/5400

Paradise adapter

the installation check for Paradise adapters is the signature “VGA=” at C000h:007Dh

Notes

IBM standard modes do not clear the screen if the high bit of AL is set (EGA or higher only) (see mode 0x8? and 0x9? and notes)

the Tseng ET4000 chipset is used by the Orchid Prodesigner II, Diamond SpeedSTAR VGA, Groundhog Graphics Shadow VGA, Boca Super X VGA

Table des matières