STG3005A2S STMicroelectronics, STG3005A2S Datasheet - Page 82

• Manufacturer Part Number: STG3005A2S
• Description: 128-BIT 3D MULTIMEDIA ACCELERATOR
• Manufacturer: STMicroelectronics

RIVA128ZX
Byte offsets 0x4F - 0x4C
AGP Command Register (0x4F - 0x4C = CAP_PTR + 8)
82/85
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
31:24
23:10
Bits
7:3
2:0
9
8
0x4F
Function
This field is set to the minimum request depth of the target as reported in its
RQ field.
Reserved
SBA_ENABLE enables sideband addressing when set. The RIVA128ZX does
not implement sideband addressing.
AGP_ENABLE allows the RIVA128ZX to act as an AGP master and initiate
AGP operations. The target must be enabled before enabling the RIVA128ZX
0 = disabled
1 = AGP operations enabled
Reserved
The DATA_RATE field must be set to 0x01 to indicate 66MHz /1x transfer
mode or 0x02 for 133MHz/2x transfer mode. This value must also be set on
the target before being enabled. The initial value 0x00 indicates PCI opera-
tion.
0x4E
128-BIT 3D MULTIMEDIA ACCELERATOR
0x4D
8
7
6
5
0x4C
4
R W 0x00
3
R W 0
R W -
R W I
R - 0
R - 0
R - 0
2
1
0