Implementation; Intel Pentium M Processor And Intel Celeron M Processor On-Die Logic Analyzer Trigger Support (Odlat); Onboard Debug Port Routing Guidelines - Intel 855PM Design Manual

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and debug groups within Intel (as well as by third party BIOS vendors, OEMs, and other developers).
For the Intel Pentium M and Intel Celeron M processors, Agilent* Corporation will develop this tool
and will likely be the only visibility to this critical system bus.
Note: Any Intel 855PM chipset based systems designed without FSB LAI support may severely limit the
ability of various Intel validation, test, and debug groups from debugging various issues in a reasonable
amount of time.
For this reason, it is critical that FSB LAI support is provided. There are two primary pieces to
providing this support:
1. Providing a motherboard with a processor socket. The FSB LAI is an interposer that plugs into
the CPU socket, and the CPU then plugs into the LAI. The use of non-standard sockets may
also prohibit the LAI from working as the locking mechanism may become inaccessible. It is
important to check the LAI design guidelines to ensure a particular socket will work. Note that
the LAI was designed to accommodate the most common (and at the time the only known) Intel
Pentium M processor sockets on the market.
2. Observing FSB LAI keepout requirements. There are several options to achieving this.
Removing the motherboard from the case is typically the first step to meeting keepout
requirements. If any components that would otherwise be in the keepout area can be relocated
for debug purposes (i.e. axial lead devices that can be de-soldered and re-soldered to the other
side of the board, parts that can be removed and blue-wired further away, etc.) that is also an
acceptable method of meeting keepout requirements. If keepouts still can not be met, Intel
strongly recommends that a separate debug motherboard be built which has the same bill of
material (BOM) and Netlist, but with FSB LAI keepout requirements met (this also gives the
opportunity to add other test-points).
4.2.2.2.

Implementation

Details from Agilent* Corporation on the FSB LAI mechanicals (i.e. design guide with keepout volume
info) are currently available for ordering. Please contact your local Intel field representative on how to
obtain the latest design info. See Section 4.3.1.4 for more details.
4.2.3. Intel Pentium M Processor and Intel Celeron M Processor On-
Die Logic Analyzer Trigger Support (ODLAT)
The Intel Pentium M and Intel Celeron M processor provides support for three address/data recognizers
on-die for setting on-die logic analyzer triggers (ODLAT) or breakpoints. Details from American
Arium* on the ODLAT are currently available for ordering.
4.3.

Onboard Debug Port Routing Guidelines

For systems incorporating the Intel Pentium M and Intel Celeron M processors, the debug port should be
implemented as either an onboard debug port or via an interposer. Please reference the document
ITP700 Debug Port Design Guide, which can be found on
http://www.intel.com/design/Xeon/guides/24967912.pdf, for the most up to date information.
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Intel 855PM Chipset Platform Design Guide
FSB Design Guidelines
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