FSB Design Guidelines
R
Intel
®
855PM Chipset Platform Design Guide
37
Table 1. FSB Common Clock Signal Internal Layer Routing Guidelines
Signal Names
Total Trace Length
CPU MCH
Transmission Line
Type
Min
(inches)
Max
(inches)
Nominal
Impedance
(
)
Width &
spacing
(mils)
ADS#
ADS#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
BNR#
BNR#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
BPRI#
BPRI#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
BR0#
BREQ0#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
DBSY#
DBSY#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
DEFER#
DEFER#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
DPWR#
DPWR#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
DRDY#
DRDY#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
HIT#
HIT#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
HITM#
HITM#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
LOCK#
HLOCK#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
RS[2:0]#
RS[2:0]#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
TRDY#
HTRDY#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
RESET#
1
CPURST#
Strip-line
1.0
6.5
55 ± 15%
4 & 8
NOTE:
For topologies where an ITP700FLEX debug port is implemented, see Section 4.1.5 for RESET#
(CPURST#) implementation details.