238
Recommended BIOS Settings
Chapter 7
AMD-761™ System Controller Software/BIOS Design Guide
24081D—February 2002
Preliminary Information
Registers
-----
Bits
Description
Initialized/
Required
Value
Actual
Value
Key
fcn( )
Notes
0x0x1x48h
DDR PDL Configuration Register 1
31:24
Clk_Dly
yyh
c
Half Period of the System Clock
23:16
SW_Cal_Dly
xxh
B
FSB
Delay for DQS:
100 MHz = 69h
133 MHz = 6Bh
15:8
Cal_Dly
yyh
c
SW_Cal_Dly in # of Buffers
7:0
Act_Dly
xxh
c
From SW_Recal or Direct Write
0x0x1x4Ch
DDR PDL Configuration Register 2
31:24
Clk_Dly
yyh
c
Half Period of the System Clock
23:16
SW_Cal_Dly
xxh
B
FSB
Delay for DQS:
100 MHz = 69h
133 MHz = 6Bh
15:8
Cal_Dly
yyh
c
SW_Cal_Dly in # of Buffers
7:0
Act_Dly
xxh
c
from SW_Recal or Direct Write
0x0x1x50h
DDR PDL Configuration Register 3
31:24
Clk_Dly yyh
c
Half Period of the System
Clock
23:16
SW_Cal_Dly
xxh
B
FSB
Delay for DQS:
100 MHz = 69h
133 MHz = 6Bh
15:8
Cal_Dly
yyh
c
SW_Cal_Dly in # of Buffers
7:0
Act_Dly
xxh
c
from SW_Recal or Direct Write
0x0x1x54h
DDR PDL Configuration Register 4
31:24
Clk_Dly yyh
c
Half Period of the System
Clock
23:16
SW_Cal_Dly
xxh
B
FSB
Delay for DQS:
100 MHz = 69h
133 MHz = 6Bh
15:8
Cal_Dly
yyh
c
SW_Cal_Dly in # of Buffers
7:0
Act_Dly
xxh
c
From SW_Recal or Direct Write
0x0x1x58h
DDR PDL Configuration Register 5
31:24
Clk_Dly
yyh
c
Half Period of the System Clock
23:16
SW_Cal_Dly
xxh
B
FSB
Delay for DQS:
100 MHz = 69h
133 MHz = 6Bh
15:8
Cal_Dly
yyh
c
SW_Cal_Dly in # of Buffers
7:0
Act_Dly
xxh
c
From SW_Recal or Direct Write
KEY:
B= Mandatory BIOS function
A= AGP setup by BIOS
c = Calculated/set by AMD-761™ internal logic
P= Power management setup by BIOS
o = Setup by OS or OS driver
F = Performance enhancement set by BIOS
r = Hardcoded and reserved
u = PCI operational user interface
E = Elective BIOS function