ICS950218 Datasheet, PDF (12/19 Pages) Integrated Circuit Systems – Programmable Timing Control Hub TM for P4 TM

Integrated
Circuit
Systems, Inc.
ICS950218
Byte 19: Group Skew Control Register
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
These 4bits control
CPU-3V66(3:2)
These 4 bits control
CPU-3V66(1:0)
PWD
0
1
0
0
0
1
0
0
Programming Sequence
0 0 0 0 0ps Reserved
0 1 0 0 150ps Reserved
1 0 0 0 300ps Reserved
1 1 0 0 450ps Reserved
1 1 0 1 600ps Reserved
1 1 1 0 750ps Reserved
1 1 1 1 900ps Reserved
Reserved
Reserved
Byte 20: Group Skew Control Register
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
These 4bits control
CPU-PCI(9:0)
Resreved
PWD
1
0
0
0
1
0
0
0
Programming Sequence
0 0 0 0 0ps Reserved
0 1 0 0 150ps Reserved
1 0 0 0 300ps Reserved
1 1 0 0 450ps Reserved
1 1 0 1 600ps Reserved
1 1 1 0 750ps Reserved
1 1 1 1 900ps Reserved
Reserved
Reserved
Byte 21: Slew Rate Control Register
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
PCICLK_2_Slew 1
PCICLK_2_Slew 1
PCICLK (1:0)_Slew 0
PCICLK (1:0)_Slew 0
3V66 (3:2)_Slew 1
3V66 (3:2)_Slew 1
3V66 (1:0)_Slew 1
3V66 (1:0)_Slew 0
PWD
1
0
1
0
1
0
1
0
Description
PCICLK2 clock slew rate control bits.
01 = strong:11 = normal; 10 = weak
PCICLK(1:0) clock slew rate control bits.
01 = strong: 11 = normal; 10 = weak
3V66 (2:1) clock slew rate control bits.
01 = strong: 11 = normal; 10 = weak
3V66 (1:0) clock slew rate control bits.
01 = strong: 11 = normal; 10 = weak
Byte 22: Slew Rate Control Register
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
REF Slew 1
REF Slew 0
PCI (9:7) Slew 1
PCI (9:7) Slew 0
PCI (6:5) Slew 1
PCI (6:5) Slew 0
PCI (4:3) Slew 1
PCI (4:3) Slew 0
PWD
1
0
1
0
1
0
1
0
Description
REF clock slew rate control bits.
01 = strong: 11 = normal; 10 = weak
PCI (9:7)) clock slew rate control bits.
01 = strong: 11 = normal; 10 = weak
PCI (6:5) clock slew rate control bits.
01 = strong: 11 = normal; 10 = weak
PCI (4:3) clock slew rate control bits.
01 = strong: 11 = normal; 10 = weak
0466B—03/17/04
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