Intel PentiumD 950 HH80553PG0964M User Manual

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Intel is working with two logic analyzer vendors to provide logic analyzer interfaces 

(LAIs) for use in debugging processor systems. Tektronix and Agilent should be 

contacted to get specific information about their logic analyzer interfaces. The following 

information is general in nature. Specific information must be obtained from the logic 

analyzer vendor. 

Due to the complexity of the processor systems, the LAI is critical in providing the 

ability to probe and capture FSB signals. There are two sets of considerations to keep in 

mind when designing a processor system that can make use of an LAI: mechanical and 

electrical.

The LAI is installed between the processor socket and the processor. The LAI lands plug 

into the processor socket, while the processor lands 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 processor heatsink. If this is the case, the logic analyzer vendor will provide a 

cooling solution as part of the LAI.

The LAI will also affect the electrical performance of the FSB; therefore, it is critical to 

obtain electrical load models from each of the logic analyzers to be able to run system 

level simulations to prove that their tool will work in the system. Contact the logic 

analyzer vendor for electrical specifications and load models for the LAI solution it 

provides.