W164 Datasheet, PDF (7/11 Pages) Cypress Semiconductor – Spread Spectrum Desktop/Notebook System Frequency Generator

W164
Table 5. Additional Frequency Selections through Serial Data Interface Data Bytes
Input Conditions
Output Frequency
Data Byte 3, Bit 3 = 1
Bit 7
SEL_3
Bit 6
SEL_2
Bit 5
SEL_1
Bit 4
SEL_0
CPU, SDRAM
Clocks (MHz)
PCI Clocks
(MHz)
0
0
0
0
68.5
34.25
0
0
0
1
75
37.5
0
0
1
0
83.3
41.6
0
0
1
1
66.8
33.4
0
1
0
0
103
34.25
0
1
0
1
112
37.3
0
1
1
0
133.3
33.3
0
1
1
1
100
33.3
1
0
0
0
117
39.0
1
0
0
1
117
29.25
1
0
1
0
124
31.0
1
0
1
1
129
32.25
1
1
0
0
138
34.5
1
1
0
1
143
35.75
1
1
1
0
148
37.0
1
1
1
1
153
38.25
If Spread Is On
Spread Percentage
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
±0.5% Center
Table 6. Select Function for Data Byte 3, Bits 0:1
Input Conditions
Data Byte 3
Function
Bit 1
Bit 0
CPU0:1
Normal Operation
0
0
Note 2
Test Mode
0
1
X1/2
Spread Spectrum
1
0
±0.5%
Three-state
1
1
Hi-Z
Note:
2. CPU and PCI frequency selections are listed in Table 1 and Table 5.
Output Conditions
PCI_F, PCI1:6
Note 2
CPU/2, 3, or 4
±0.5%
Hi-Z
REF2X,
IOAPIC
14.318 MHz
X1
14.318 MHz
Hi-Z
48MHZ
48 MHz
X1/2
48 MHz
Hi-Z
24MHZ
24 MHz
X1/4
24 MHz
Hi-Z
Rev 1.0, November 28, 2006
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