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AMD-761™ System Controller Programmer’s Interface
Chapter 2
AMD-761™ System Controller Software/BIOS Design Guide
24081D—February 2002
Preliminary Information
DDR PDL Calibration Control
Dev0:F1:0x40
Register Description
This register allows BIOS control of the calibration circuit for the AMD-761™ system controller’s 18 programmable delay
lines.
Note that this register is not initialized at reset time but must be initialized by BIOS for proper operation. This action
should be done prior to attempting DRAM access.
31
30
29
28
27
26
25
24
Bit
Reserved
Reset
0
0
0
0
0
0
0
0
R/W
R
23
22
21
20
19
18
17
16
Bit
Reserved
Reset
0
0
0
0
0
0
0
0
R/W
R
15
14
13
12
11
10
9
8
Bit
Reserved
Reset
0
0
0
0
0
0
0
0
R/W
R
7
6
5
4
3
2
1
0
Bit
SW_Recal
Use_Act_Dly Auto_Cal_En Act_Dly_Inh
Reserved
Auto_Cal_Period
Reset
X
X
X
X
0
0
X
X
R/W
R/W
W
R/W
R/W
R
R/W