Riser Card Topologies; Typical Hot-Plug Topology - Intel Pentium M Processor Design Manual

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Intel Pentium M Processor and Intel
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Intel 82870P2 (Intel P64H2)
Figure 84.

Typical Hot-Plug Topology

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Table 64. Intel P64H2 Hot-Plug Length Requirements
Configuration
66 MHz, 4 Slots / 0 Device
100 MHz, 2 Slots / 1 Device
100 MHz, 2 Slots / 0 Device
100 MHz, 1 Slot / 1 Device
133 MHz, 1 Slot / 0 Devices
NOTE: During simulation, slot to slot lengths were held constant for some configurations. Therefore, no range
may be given for these length requirements.
8.1.4

Riser Card Topologies

The following guidelines are for systems that use a PCI-X riser card. A PCI-X riser card is card
intended to extend the PCI-X signals. The riser card will contain a PCI-X card edge break-out and
PCI-X connector slots. The riser's PCI-X card edge break-out is plugged into the motherboard's
PCI-X slot and the riser's PCI-X connector slots are used to plug in PCI-X adapter cards. These
guidelines assume a PCI/PCI-X riser card with a 0.7 – 1.0 inch long trace length between slots.
These simulations require the clocks for each device and riser card slot to be tuned within 500 ps,
or 2.85 inches, of each other. For the riser slot to also support a standard PCI/PCI-X adapter card,
the tuning must also include the adapter card length.
The following topologies denote an upper and lower portion to the length requirements. The PCI
specification requires the original 32-bit signals to have a card length of 0.75 to 1.5 inches. The
64-bit extension specifies the additional signals in the extension to have a length of 1.75 inches to
2.75 inches. Upper indicates the signals on the extension while Lower indicates signals lying in the
original 32-bit space.
In some of the riser card topologies, series resistors are required. These series resistors must be
placed on all signals listed in
126
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E7501 Chipset Platform
P64H2 to
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Intel
Switch
P64H2
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Intel
Switch
2.0" – 6.0"
2.5" – 3.5"
3.5" – 4.5"
4.0" – 5.0"
1.5" – 3.5"
Table
Switch to
Switch1
Slot
Switch to
Switch2
Switch
Switch to
Device Down
P64H2 to
Switch to Slot
0.5" – 3.0"
0.5" – 0.75"
1.0" – 1.75"
1.75" – 2.25"
0.5" – 3.0"
61.
Slot 1
Slot 2
Switch to
Slot
Device
Down
Switch to
Switch to Switch
Device Down
0.5" N/A
0.75" 1.5" – 2.5"
1.0" – 1.75" N/A
N/A 3.5" – 4.5"
N/A N/A
Design Guide