ICS951413 Datasheet, PDF (14/23 Pages) Integrated Circuit Systems – Programmable System Clock Chip for ATI RS400 P4-based Systems

Integrated
Circuit
Systems, Inc.
ICS951413
SMBus Table: SRC Spread Spectrum Control Register
Byte 18 Pin #
Name
Control Function
Bit 7
-
Reserved
Reserved
Bit 6
-
SSP14
Bit 5
-
SSP13
Bit 4
-
Bit 3
-
Bit 2
-
SSP12
SSP11
SSP10
Spread Spectrum
Programming b(14:8)
Bit 1
-
SSP9
Bit 0
-
SSP8
Type
0
1
R
-
-
RW
RW
RW
These Spread Spectrum
bits in Byte 17 and 18 will
RW
program the spread
RW
pecentage of SRC
RW
RW
PWD
0
X
X
X
X
X
X
X
SMBus Table: Programmable Output Divider Register
Byte 19 Pin #
Name
Control Function
Bit 7
-
Bit 6
-
Bit 5
-
CPUDiv3
CPUDiv2
CPUDiv1
CPU Divider Ratio
Programming Bits
Bit 4
-
CPUDiv0
Bit 3
-
Bit 2
-
Bit 1
-
PCIDiv3
PCIDiv2
PCIDiv1
PCI Divider Ratio
Programming Bits
Bit 0
-
PCIDiv0
Type
0
1
RW
RW See Table 3: CPU Divider
RW
Ratios
RW
RW
RW See Table 4: PCI Divider
RW
Ratios
RW
PWD
X
X
X
X
X
X
X
X
SMBus Table: Programmable Output Divider Register
Byte 20 Pin #
Name
Control Function
Bit 7
-
Bit 6
-
Bit 5
-
SRC_Div3
SRC_Div2
SRC_Div1
SRC_ Divider Ratio
Programming Bits
Bit 4
-
SRC_Div0
Bit 3
-
Bit 2
-
Bit 1
-
ATIG_Div3
ATIG_Div2
ATIG_Div1
ATIG_ Divider Ratio
Programming Bits
Bit 0
-
ATIG_Div0
Type
RW
RW
RW
RW
RW
RW
RW
RW
0
1
See Table 5: ATIG and
SRC Divider Ratios
PWD
X
X
X
X
X
X
X
X
SMBusTable: Test Byte Register
Byte 21 Test
Test Function
Bit 7
`
ICS ONLY TEST
Bit 6
ICS ONLY TEST
Bit 5
ICS ONLY TEST
Bit 4
ICS ONLY TEST
Bit 3
ICS ONLY TEST
Bit 2
ICS ONLY TEST
Bit 1
ICS ONLY TEST
Bit 0
ICS ONLY TEST
Type
RW
RW
RW
RW
RW
RW
RW
RW
Test Result
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
PWD
0
0
0
0
0
0
0
0
0929C—03/07/05
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