Intel 6300ESB ICH, Design Manual

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72
Intel
®
855GME Chipset and Intel
®
6300ESB ICH Embedded Platform Design Guide
4.1.10 Pentium
®
M/Celeron
®
M Processor System Bus Strapping
The Intel Pentium M/Celeron M processor and GMCH both have pins that require termination for
proper component operation.
For the Intel Pentium M/Celeron M processor, a stuffing option shall be provided for the TEST[3]
pin to allow a 1 k
Ω
±5 percent pull-down to ground for testing purposes. For proper processor
operation, the resistor shall not be stuffed. Resistors for the stuffing option on these pins shall be
placed within 2.0 inches of the Intel Pentium M/Celeron M processor.
Figure 2 illustrates the
recommended layout for the stuffing options. For normal operation, these resistors shall not be
stuffed.
The Intel Pentium M/Celeron M processor’s ITP signals, TDI, TMS, TRST and TCK shall assume
default logic values even if the ITP debug port is not used. The TDO signal may be left open or no
connect in this case.
Table 18 summarizes the default strapping resistors for these signals. These
resistors shall be connected to the Intel Pentium M/Celeron M processor within 2.0 inches from
their respective pins.
Note: Table 18 is applicable only when neither the onboard ITP nor ITP interposer are planned to be
used. Refer to Section 4.2.2 on cautions against designs with lack of debug tools support. Intel does
not recommend use of the ITP interposer debug port if there is a dependence only on the
motherboard termination resistors.
Figure 33. COMP2 and COMP0 18-mil Wide Dog Bones and Traces
PRIMARY SIDE SECONDARY SIDE
SECONDARY SIDE
COMP0
18 - mil Dog Bone
18 - mil Trace
27.4
Ω
1%
27.4
CO MP1
PRIMARY SIDE
PRIMARY SIDE
SECONDARY SIDE
SECONDARY SIDE
COMP0
COMP2
18- mil Dog Bone
18 -mil Trace
27.4
Ω
1%
27.4
Ω
1%
COMP1
COMP3