
932S890C
RD890 SYSTEM CLOCK FOR AMD-BASED SERVERS
IDT
RD890 SYSTEM CLOCK FOR AMD-BASED SERVERS
13
932S890C
REV D 052011
SMBus Table: Output Enable Control Register
B yte
0
Name
Description
Type
0
1
Default
Bit 7
HTT1_OE
Output Enable
RW
Low /Low
Enabled
1
Bit 6
HTT0_OE
Output Enable
RW
Low /Low
Enabled
1
Bit 5
REF0_OE
Output Enable
RW
Low
Enabled
1
Bit 4
REF1_OE
Output Enable
RW
Low
Enabled
1
Bit 3
SIO_0_OE
Output Enable
RW
Hi-Z
Enabled
1
Bit 2
SIO_1_OE
Output Enable
RW
Low
Enabled
1
Bit 1
48MHz_1_OE
Output Enable
RW
Low
Enabled
1
Bit 0
48MHz_0_OE
Output Enable
RW
Low
Enabled
1
SMBus Table:Output Enable Control Register
Byte
1
Name
Control Function
Type
0
1
Default
Bit 7
SR C13_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 6
SR C12_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 5
SR C11_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 4
SR C10_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 3
SRC9_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 2
SRC8_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 1
SRC7_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 0
SRC6_OE
Output Enable
R W
Low /Low
Enabled
1
SMBus Table: Output Enable Control Register
Byte
2
Name
Control Function
Type
0
1
Default
Bit 7
SRC5_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 6
SRC4_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 5
SRC3_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 4
SRC2_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 3
SRC1_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 2
SRC0_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 1
SATA_OE
Output Enable
R W
Low /Low
Enabled
1
Bit 0
CPU0_OE
Output Enable
R W
Low /Low
Enabled
1
SMBus Table: CPU/H TT Frequency and Output Enable Control Register
Byte
3
Name
Control Function
Type
0
1
Default
Bit 7
CPU3_OE
Output enable
R W
Low /Low
Enabled
1
Bit 6
CPU2_OE
Output enable
R W
Low /Low
Enabled
1
Bit 5
CPU1_OE
Output enable
R W
Low /Low
Enabled
1
Bit 4
CPU SS Enable
Spread Enable
R W
SS Off
SS On
0
Bit 3
CPU Spread Type
Dow n or Center Spread
RW
0.5% Dow n Spread
0.5% Center Spread
(+/-0.25%)
0
Bit 2
CPU_FS2
CPU Frequency Select
RW
1
Bit 1
CPU_FS1
CPU Frequency Select
R W
0
Bit 0
CPU_FS0
CPU Frequency Select LSB
RW
0
SMBus Table: SRC Frequency C ontrol Register
Byte
4
Name
Control Function
Type
0
1
Default
Bit 7
0
Bit 6
0
Bit 5
0
Bit 4
SRC SS Enable
Spread Enable
R W
SS Off
SS On
0
Bit 3
SRC Spread Type
Dow n or Center Spread
RW
0.5% Dow n Spread
0.5% Center Spread
0
Bit 2
SRC_FS2
SRC Frequency Select
RW
1
Bit 1
SRC_FS1
SRC Frequency Select
R W
0
Bit 0
SRC_FS0
SRC Frequency Select LSB
RW
0
Reserved
See CPU Frequency Select Table
Default value corresponds to 200MHz.
Note that HTT frequency tracks the CPU frequency
and is equal to 1/2 for C PU.
See SRC Frequency Select Table
Default Corresponds to 100MHz