
C9726
Clock Generator for VIA VT8371/Athlon (K7) Chipset Systems
Approved Product
Cypress Semiconductor Corporation
525 Los Coches St.
Milpitas, CA 95035. Tel: 408-263-6300, Fax: 408-263-6571
http://www.cypress.com
Document#: 38-07047 Rev. **
05/03/2001
Page 7 of 16
Frequency Selection Table
Input Conditions
Data Byte 0, Bit 3 = 1
Bit2
S4
S3
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Output
Frequency
CPU
Spread%
Bit 1
Bit 6
S2
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
Bit 5
S1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
Bit 4
S0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
PCI
Byte0, Bit7 = 0
Byte0, Bit7 = 1
133.3
75
100.2
66.8
79
110
115
120
133.3
83.3
100.2
66.8
124
129
138
143
85
87.5
90
92.5
95
147
152
154
157
159
162
166
171
180
190
200
33.3
37.5
33.3
33.4
39.5
36.7
38.3
30
33.3
27.7
33.3
33.4
31.0
32.3
34.5
35.8
28.3
29.2
30
30.8
31.7
36.8
30.4
30.8
31.4
31.8
32.4
33.2
34.2
36
38
40
+/-0.5
+/-0.5
+/-0.5
+/-0.5
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
See table 3, Page 6
Table 6.
Dial-a-Frequency
Feature
See Ap Note AN-0025 for a description of the Dial-a-Frequency Feature
P is a large value PLL constant that depends on the frequency selection achieved through the hardware
selectors (S3, S2, S1, S0) or through the software selectors (byte0, bits 6,5,4,2,1). P value may be
determined from the following table: