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Method for Switching Trace Data Based on Current Trace Results and Controlling Patching and Tracing from the Service Processor or System Code

IP.com Disclosure Number: IPCOM000117780D
Original Publication Date: 1996-Jun-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 59K

Publishing Venue

IBM

Related People

Day, LL: AUTHOR [+3]

Abstract

Disclosed is a method for changing the input data into the trace logic based on the current state of the trace state machine. The trace state machine controls the muxing of all data into the trace logic. The state machine may change the data muxing every cycle based off its program.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Method for Switching Trace Data Based on Current Trace Results and
Controlling Patching and Tracing from the Service Processor or System
Code

      Disclosed is a method for changing the input data into the
trace logic based on the current state of the trace state machine.
The trace state machine controls the muxing of all data into the
trace logic.  The state machine may change the data muxing every
cycle based off its program.

      Also, this invention allows system operating code and/or the
service processor to control the trace/patch logic on the chip.  This
control is accomplished with all basic control registers being
available for reading and writing by the operating system code and/or
the service processor.

      Past trace arrays relied on setting up the data to be traced at
the beginning of the test.  Therefore, the data to be traced had to
be available to the input of the trace array from the start.  But
with hardware limitations restricting the size, width in particular,
of the trace arrays, one can no longer count on having all the needed
data coming into the trace array at one time.

      This solution involves setting up a trace state machine that
uses a microcontroller of multiple trace control words with each word
having independent control over what data is allowed to enter the
trace logic.  As various conditions are found, the microcontroller
will advance through different trace control words which then will
allow different data to be directed into the t...