Integrated Functions (Continued)
Table 4-36 summarizes the VGA Configuration Registers.
Detailed register/bit formats are given in Table 4-37. See
Section 3.3.2.2 “Configuration Registers” on page 50 on
how to access these registers.
Table 4-36. VGA Configuration Registers Summary
Index
Type
Name/Function
Default Value
B9h
R/W
R/W
VGACTL: VGA Control Register
VGAM: VGA Mask Register
00h (SMI generation disabled)
xxxxxxxxh
BAh-BDh
Table 4-37. VGA Configuration Registers
Bit
Description
Index B9h
VGACTL Register (R/W)
Default Value = 00h
7:3
2
Reserved: Set to 0.
SMI generation for VGA memory range B8000h to BFFFFh: 0 = Disable; 1 = Enable.
SMI generation for VGA memory range B0000h to B7FFFh: 0 = Disable; 1 = Enable.
SMI generation for VGA memory range A0000h to AFFFFh: 0 = Disable; 1 = Enable.
1
0
Index BAh-BDh
VGAM Register (R/W)
Default Value = xxxxxxxxh
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
SMI generation for address range AF800h to AFFFFh: 0 = Disable; 1 = Enable.
SMI generation for address range AF000h to AF7FFh: 0 = Disable; 1 = Enable.
SMI generation for address range AE800h to AEFFFh: 0 = Disable; 1 = Enable.
SMI generation for address range AE000h to AE7FFh: 0 = Disable; 1 = Enable.
SMI generation for address range AD800h to ADFFFh: 0 = Disable; 1 = Enable.
SMI generation for address range AD000h to AD7FFh: 0 = Disable; 1 = Enable.
SMI generation for address range AC800h to ACFFFh: 0 = Disable; 1 = Enable.
SMI generation for address range AC000h to AC7FFh: 0 = Disable; 1 = Enable.
SMI generation for address range AB800h to ABFFFh: 0 = Disable; 1 = Enable.
SMI generation for address range AB000h to AB7FFh: 0 = Disable; 1 = Enable.
SMI generation for address range AA800h to AAFFFh: 0 = Disable; 1 = Enable.
SMI generation for address range AA000h to AA7FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A9800h to A9FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A9000h to A97FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A8800h to A8FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A8000h to A87FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A7800h to A7FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A7000h to A77FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A6800h to A6FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A6000h to A67FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A5800h to A5FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A5000h to A57FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A4800h to A4FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A4000h to A47FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A3800h to A3FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A3000h to A37FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A2800h to A2FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A2000h to A27FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A1800h to A1FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A1000h to A17FFh: 0 = Disable; 1 = Enable.
SMI generation for address range A0800h to A0FFFh: 0 = Disable; 1 = Enable.
SMI generation for address range A0000h to A07FFh: 0 = Disable; 1 = Enable.
8
7
6
5
4
3
2
1
0
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