Intel Pentium 4 672 HH80547PG1122MH User Manual

                                               

   

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Intel is working with two logic analyzer vendors to provide logic analyzer interfaces (LAIs) for use 
in debugging Pentium 4 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 Pentium 4 processor systems, the LAI is critical in providing the ability to 
probe and capture system bus signals. There are two sets of considerations to keep in mind when 
designing a Pentium 4 processor system that can make use of an LAI: mechanical and electrical.

The LAI is installed between the processor socket and the Pentium 4 processor. The LAI pins plug 
into the socket, while the Pentium 4 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 Pentium 4 
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 include space normally 
occupied by the Pentium 4 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 system bus; 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 they provide.