Signal Description
2.18
System Setup
2.18.1
Clocking
In addition to 33-MHz and 66-MHz PCI output clocking, the Intel® 6702PXH 64-bit PCI Hub
requires 100-MHz and 133-MHz outputs to support PCI-X. Table 2-36 shows the Intel® 6702PXH
64-bit PCI Hub clock domains.
Table 2-36. Intel® 6702PXH 64-bit PCI Hub Clocking
Clock Domain
Frequency
Source
External
Usage
PCI Express*
PCI
100 MHz Differential
133/100/66/33 MHz
10-100KHz
PCI Express* differential clocks.
Internal
PCI Bus. These only go to the external PCI Bus.
SMBus
Source
Synchronous
This pin is controlled by the driver of the SMBus
interface, and will run between 10 and 100 kHz.
TCK
0-16 MHz
External
JTAG clock.
Figure 2-12. Intel® 6702PXH 64-bit PCI Hub Clocking Diagram
The Intel® 6702PXH 64-bit PCI Hub component uses a 100-MHz differential pair clock inputs to
generate all of its core and PCI clocks. The differential clock inputs EXP_CLK and EXP_CLK#
are part of the PCI Express interface. Board design must insure that all voltages supplying the
Intel® 6702PXH 64-bit PCI Hub (VCC, VCCEXP, VCC33 and VCC15) are valid before these PCI
Express clocks begin running.
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Intel® 6702PXH 64-bit PCI Hub Datasheet
INTEL [ INTEL ]
