ICS9LPRS480 Datasheet, PDF (21/25 Pages) Integrated Device Technology – Programmable System Clock Chip for ATI RS780 - K8TM based Systems

Integrated
Circuit
Systems, Inc.
ICS9LPRS480
Byte
17
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SMBUS Table: SB_SRC Frequency Control Register
Name
Control Function Type
N Div10
RW
N Div9
RW
N Div8
N Div7
N Div6
N Div5
RW
N Divider Programming
RW
Byte16 bit(7:0) and Byte15
bit(7:6)
RW
RW
N Div4
RW
N Div3
RW
0
1
The decimal representation of M and N Divider in
Byte 16 and 17 configure the SB_SRC VCO
frequency. See M/N Caculation Tables for VCO
frequency formulas.
Default
X
X
X
X
X
X
X
X
Byte
18
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SMBUS Table: SB_SRC Spread Spectrum Control Register
Name
Control Function Type
0
1
SSP7
RW
SSP6
RW
SSP5
SSP4
SSP3
SSP2
Spread Spectrum
Programming bit(7:0)
RW
RW
Bytes 18 and 19 set the the SB_SRC spread
pecentages. Please contact ICS for the
RW
appropriate values.
RW
SSP1
RW
SSP0
RW
Default
X
X
X
X
X
X
X
X
Byte
19
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SMBUS Table: SB_SRC Spread Spectrum Control Register
Name
Control Function Type
0
1
SSP15
RW
SSP14
RW
SSP13
SSP12
SSP11
SSP10
Spread Spectrum
Programming bit(14:8)
RW
RW
Bytes 18 and 19 set the the SB_SRC spread
pecentages. Please contact ICS for the
RW
appropriate values.
RW
SSP9
RW
SSP8
RW
Default
X
X
X
X
X
X
X
X
Byte
20
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SMBUS Table: SB_SRC Output Divider Control Register
Name
Control Function Type
SB_SRC NDiv0
LSB N Divider Programming RW
Reserved
Reserved
Reserved
SB_SRCDiv3
RW
SB_SRCDiv2
SB_SRCDiv1
SRC Divider Ratio
RW
Programming Bits
RW
SB_SRCDiv0
RW
0
1
SB_SRC M/N programming.
0000:/2 ; 0100:/4
0001:/3 ; 0101:/6
0010:/5 ; 0110:/10
0011:/15 ; 0111:/18
1000:/8 ; 1100:/16
1001:/12 ; 1101:/24
1010:/20 ; 1110:/40
1011:/36 ; 1111:/72
Default
X
X
X
X
X
X
X
X
Byte
21
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SMBus Table: Device ID register
Name
Control Function
Device ID7
Device ID6
Device ID5
Device ID4
Device ID3
Device ID
Device ID2
Device ID1
Device ID0
Type
R
R
R
R
R
R
R
R
0
1
76 hex
Default
0
1
1
1
0
1
1
0
1391D—02/02/09
21