Debug Tools Specifications
8 Debug Tools Specifications
For debug purposes, the socket LS pin definition has allocated signals to install a logic
analyzer probe head to observe Intel QPI traffic.
8.1
Logic Analyzer Interface
Due to the complexity of Intel Xeon Processor E7-8800/4800/2800 Product Families
processor-based multiprocessor systems, the Logic Analyzer Interface (LAI) is critical in
providing the ability to probe and capture high-speed signals. There are two sets of
considerations to keep in mind when designing a Intel Xeon Processor E7-8800/4800/
2800 Product Families processor-based system that can make use of an LAI:
mechanical and electrical.
8.1.1
Mechanical Considerations
The LAI is installed between the processor socket and the processor. The LAI pins plug
into the socket, while the processor pins plug into a socket on the LAI. Cabling that is
part of the LAI egresses the system to allow an electrical connection between the
processor and a logic analyzer. The maximum volume occupied by the LAI, known as
the keepout volume, as well as the cable egress restrictions, should be obtained from
the logic analyzer vendor. System designers must make sure that the keepout volume
remains unobstructed inside the system. Note that it is possible that the keepout
volume reserved for the LAI may differ from the space normally occupied by the Intel
Xeon Processor E7-8800/4800/2800 Product Families processor heatsink. If this is the
case, the logic analyzer vendor will provide a cooling solution as part of the LAI.
8.1.2
Electrical Considerations
Instrumented Intel QPI links will require equalization settings unique for that topology.
The platform will need to load updated optimized equalization settings for instrumented
links. The method of obtaining the new set of E.Q settings is via the Signal Integrity
Support Tools for Advanced Interfaces (SISTAI) tools, following the same procedures.
§
Datasheet Volume 1 of 2
173
INTEL [ INTEL ]
