VT8601 Via, VT8601 Datasheet - Page 46

• Manufacturer Part Number: VT8601
• Description: Slot-1 / Socket-370 PCI North Bridge
• Manufacturer: Via

Device 0 Offset 61 - Shadow RAM Control 1 ................. RW
Device 0 Offset 62 - Shadow RAM Control 2 ................. RW
Revision 1.3 September 8, 1999
7-6
5-4
3-2
1-0
7-6
5-4
3-2
1-0
7HFKQRORJLHV ,QF
CC000h-CFFFFh
C8000h-CBFFFh
C4000h-C7FFFh
C0000h-C3FFFh
DC000h-DFFFFh
D8000h-DBFFFh
D4000h-D7FFFh
D0000h-D3FFFh
:H &
:H &R R QQHFW
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ..................................default
01 Write enable
10 Read enable
11 Read/write enable
QQHFW
-40-
Device 0 Offset 63 - Shadow RAM Control 3 ................. RW
7-6
5-4
3-2
1-0
E0000h-EFFFFh
F0000h-FFFFFh
Memory Hole
SMI Mapping Control
Note: The A0000-BFFFF address range is reserved
for use by VGA controllers for system access to the
VGA frame buffer. Since frame buffer accesses are
normally directed to the system VGA controller (with
its separate memory subsystem), system DRAM
locations in the A0000-BFFFF range would normally
be unused.
allows this block of system memory to be used by
directing Axxxx-Bxxxx accesses to corresponding
memory addresses in system DRAM instead of
directing those accesses to the PCI bus for VGA
frame buffer access.
00 Read/write disable ................................. default
01 Write enable
10 Read enable
11 Read/write enable
00 Read/write disable ................................. default
01 Write enable
10 Read enable
11 Read/write enable
00 None .................................................... default
01 512K-640K
10 15M-16M (1M)
11 14M-16M (2M)
00 Disable SMI Address Redirection ......... default
01 Allow access to DRAM Axxxx-Bxxxx for both
10 Reserved
11 Allow SMI Axxxx-Bxxxx DRAM access
normal and SMI cycles
Setting the above bits appropriately
Device 0 Bus 0 Host Bridge Registers
VT8601 Apollo ProMedia