W48S87-72 Datasheet, PDF (8/19 Pages) Cypress Semiconductor – Desktop/Notebook Frequency Generator

W48S87-72
Table 5. Additional Frequency Selections through Serial Data Interface Data Bytes
Date Byte 0
Date Byte 7
Bit 5
SEL_4
Bit 4 60/66_SEL Bit 2
SEL_3
(Pin 18)
SEL_2
BIT 1
SEL_1
BIT 0
CPU0:3
SEL_0 SDRAM0:7
0
0
X
0
0
0
75.0
0
0
X
0
0
1
75.0
0
0
X
0
1
0
83.31
0
0
X
0
1
1
33.41
0
0
X
1
0
0
50.11
0
0
X
1
0
1
68.52
0
0
X
1
1
0
60.0
0
0
0
1
1
1
60.0
0
0
1
1
1
1
66.82
0
1
0
X
X
X
60.0
0
1
1
X
X
X
66.6
1
0
0
X
X
X
60.0
1
0
1
X
X
X
66.6
1
1
0
X
X
X
60.0
1
1
1
X
X
X
66.6
PCI_F
PCI0:5
CPU/2
32
32
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
CPU/2
Spread
Spectrum%
±0.5
±0.5
±0.5
±0.5
±0.5
±0.5
±0.5
±0.5
±0.5
±0.5
–0.5
±0.5
–0.5
±0.5
–0.5
Table 6. Select Function for Data Byte 0, Bits 0:1
Input Conditions
Function
Data Byte 0
Bit 1
Bit 0
CPU0:3,
SRAM0:7
Normal Operation
0
0
Note 2
Test Mode
0
1
X1/2
Spread Spectrum On
1
0
Note 2
Three-state
1
1
Hi-Z
Notes:
2. CPU, SDRAM, and PCI frequency selections are listed in Table 1 and Table 5.
3. In Test Mode, the 48-/24-MHz clock outputs are:
- X1/2 if 48-MHz is selected.
- X1/4 if 24-MHz is selected.
Output Conditions
PCI_F,
PCI0:5
Note 2
X1/4
Note 2
Hi-Z
REF0:2, IOAPIC
14.318 MHz
X1
14.318 MHz
Hi-Z
48/24MHZ
48 or 24 MHz
Note 3
48 or 24 MHz
Hi-Z
8