Specifications

Intel
®
810E2 Chipset Platform
R
Design Guide
163
7.2. Intel
®
ICH2 Checklist
7.2.1. PCI Interface
Checklist Items Recommendations
All All inputs to the ICH2 must not be left floating. Many GPIO signals are fixed inputs that
must be pulled up to different sources. See GPIO section for recommendations.
PERR#, SERR#
PLOCK#, STOP#
DEVSEL#, TRDY#
IRDY#, FRAME#
REQ#[0:4],
GPIO[0:1], THRM#
These signals require a pull-up resistor. Recommend an 8.2 k
Ω pull-up resistor to VCC3.3
or a 2.7 k
Ω pull-up resistor to VCC5. See PCI 2.2 Component Specification for pull-up
recommendations for VCC3.3 and VCC5.
PCIRST# The PCIRST# signal should be buffered to form the IDERST# signal.
33
Ω series resistor to IDE connectors.
PCIGNT# No external pull-up resistors are required on PCI GNT signals. However, if external pull-up
resistors are implemented they must be pulled up to VCC3.3.
PME# This signal has an integrated pull-up of 24K.
SERIRQ External weak (8.2 kΩ) pull-up resistor to VCC3.3 is recommended.
GNT[A]# /GPIO[16],
GNT[B]/ GNT[5]#/
GPIO[17]
No extra pull-up needed. These signals have integrated pull-ups of 24 kΩ.
GNT[A] has an added strap function of “top block swap”. The signal is sampled on the
rising edge of PWROK. Default value is high or disabled due to pull-up. A Jumper to a pull-
down resistor can be added to manually enable the function.
7.2.2. Hub Interface
Checklist Items Recommendations
HL[11] No pull-up resistor required. Use a no-stuff or a test point to put the ICH2 into NAND chain
mode testing
HL_COMP Tie the COMP pin to a 40 Ω 1% or 2% (or 39 Ω - 1%) pull-up resistor (to VCC1.8) via a
10-mil wide, very short (~0.5 inch) trace. ZCOMP No longer supported.
7.2.3. LAN Interface
Checklist
Items
Recommendations Comments
1 Trace Spacing: 5 mils wide, 10 mil spacing
2 LAN Max Trace Length Intel
®
ICH2 to CNR:
L = 3” to 9” (0.5” to 3” on card)
To meet timing
requirements.
3 Stubs due to R-pak CNR/LOM stuffing option should not be
present.
To minimize inductance.
4 Maximum Trace Lengths: ICH2 to Intel
®
82562EH: L = 4.5
inches to 10 inches; 82562ET: L = 3.5 inches to 10 inches;
82562EM: L = 4.5 inches to 8.5 inches.
To meet timing
requirements.