RIVA128ZX Datasheet, PDF (71/85 Pages) STMicroelectronics – 128-BIT 3D MULTIMEDIA ACCELERATOR

128-BIT 3D MULTIMEDIA ACCELERATOR
RIVA128ZX
Command Register (0x05 - 0x04)
Bits Function
15:9 Reserved
8
SERR_ENABLE is an enable bit for the SERR# driver.
0=Disables the SERR# driver
1=Enables the SERR# driver
7:6
Reserved
5
PALETTE_SNOOP indicates that VGA compatible devices should snoop their
palette registers.
0=Palette accesses treated like all other accesses
1=Enables special palette snooping behavior
4
WRITE_AND_INVAL is an enable bit for using the Memory Write and Invali-
date command.
1=The RIVA128ZX as bus master may generate the command
0=The Memory Write command must be used instead of Memory Write and
Invalidate
3
Reserved
2
BUS_MASTER indicates that the device can act as a master on the PCI bus.
0=Disables the RIVA128ZX from generating PCI accesses
1=Allows the RIVA128ZX to behave as a bus master
1
MEMORY_SPACE indicates that the RIVA128ZX will respond to memory
space accesses.
0=Device response disabled
1=Enables response to Memory space accesses. The device will decode and
respond to the 16MByte ranges as well as the default VGA memory range
when it is enabled. The VGA decode range may change based upon the
value in the VGA graphics Miscellaneous Register GR06, bits[3:2] and other
enable bits, see RIVA128ZX Programming Reference Manual [2].
0
IO_SPACE indicates that the device will respond to I/O space accesses. This
bit enables I/O space accesses for the VGA function as defined in the PCI
specification. These include 0x3B0 - 0x3BB, 0x3C0 - 0x3DF and their aliases.
RWI
R-0
RW0
R-0
RW0
RW0
R-0
RW0
RW0
RW0
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