ICS94228 Datasheet, PDF (6/17 Pages) Integrated Circuit Systems – Programmable System Clock Chip for AMD - K7™ processor

ICS94228
Serial Configuration Command Bitmap
Byte0: Functionality and Frequency Select Register (default = 0)
Bit5
SSB1
Bit4
SSB0
Bit3 Bit2 Bit1 Bit0
FS3 FS2 FS1 FS0
CPUCLK
AGPCLK
PCICLK
0
0 0000
233.33 77.78
38.88
0
0 0001
220.00 73.33
36.67
0
0 0010
210.00 70.00
35.00
0
0 0011
200.00 66.67
33.33
0
0 0100
190.00 76.00
38.00
0
0 0101
180.00 72.00
36.00
0
0 0110
170.00 68.00
34.00
0
0 0111
150.00 75.00
37.50
0
0 1000
140.00 70.00
35.00
0
0 1001
120.00 60.00
30.00
0
0 1010
110.00 66.00
33.00
0
0 1011
66.67
66.67
33.33
0
0 1100
200.00 66.67
33.33
0
0 1101
166.67 66.67
33.33
0
0 1110
100.00 66.67
33.33
0
0 1111
133.33 66.67
33.33
0
1 0000
200.00 66.67
33.33
0
1 0001
166.67 66.67
33.33
0
1 0010
100.00 66.67
33.33
0
1 0011
133.33 66.67
33.33
1
0 0100
200.00 66.67
33.33
1
0 0101
166.67 66.67
33.33
1
0 0110
100.00 66.67
33.33
1
0 0111
133.33 66.67
33.33
1
1 1000
200.00 66.67
33.33
1
1 1001
166.67 66.67
33.33
1
1 1010
100.00 66.67
33.33
1
1 1011
133.33 66.67
33.33
1
0 1100
200.00 66.67
33.33
1
0 1101
166.67 66.67
33.33
1
0 1110
100.00 66.67
33.33
1
0 1111
133.33 66.67
33.33
Bit 6: 0 = Hardware select; 1 = I²C select. Default is OFF.
Bit 7: 0 = Spread off; 1 = Spread spectrum enable. Default is OFF
Spread Percentage
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
+/- 0.25% Center Spread
0 to -0.5% Down Spread
0 to -0.5% Down Spread
0 to -0.5% Down Spread
0 to -0.5% Down Spread
+/- 0.50% Center Spread
+/- 0.50% Center Spread
+/- 0.50% Center Spread
+/- 0.50% Center Spread
+/- 0.75% Center Spread
+/- 0.75% Center Spread
+/- 0.75% Center Spread
+/- 0.75% Center Spread
0 to +0.5% Up Spread
0 to +0.5% Up Spread
0 to +0.5% Up Spread
0 to +0.5% Up Spread
0447E—05/07/04
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