QG5000XSL9TH Datasheet, PDF (311/458 Pages) Intel Corporation – Intel 5000X Chipset Memory Controller Hub (MCH)

Functional Description
Figure 5-7. FB-DIMM Channel Schematic
NORTHBOUND
14
SOUTHBOUND
10
NORTHBOUND
14
SOUTHBOUND
10
CLOCK
GENERATOR
A FB-DIMM channel consists of 14 unidirectional differential signal pairs referred to as
the Northbound path, 10 unidirectional differential signal pairs referred to as the
Southbound path, and a differential reference clock.
NOTE: The northbound signal pairs are enumerated from 0 to 13. Signal pair 13 is not
active but must be connected to properly terminate the FB-DIMM channel. See
sections, Figure 2.2.1, “FB-DIMM Branch 0” on page 29 and Figure 2.2.2, “FB-DIMM
Branch 1” on page 30.
The southbound path is used to convey DIMM commands and write data to the
addressed DIMMs. The northbound path returns read data and status from the
addressed DIMM.
The northbound and southbound paths are used to convey FB-DIMM frames that are
synchronized to the reference clock. Each frame consists of 12 data transfers.
Southbound frames contain a payload of 8 bytes per frame per channel. Northbound
frames contain a payload of 16 bytes per frame per channel.
Intel^® 5000X Chipset Memory Controller Hub (MCH) Datasheet
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