Agilent Technologies FS2334 Manuale Utente
17
TimingZoom Analysis
The TimingZoom feature of the 1690x logic analyzer allows for efficient timing analysis
of all the signals on the DDR2 DIMM bus.
of all the signals on the DDR2 DIMM bus.
Please refer to the “Setting up the 16900 Analyzer” section of this manual on the use of
the general purpose probe feature to determine how to attach the logic analyzer to the
probe.
the general purpose probe feature to determine how to attach the logic analyzer to the
probe.
Load the logic analyzer configuration file for timing, FS234_2. It doesn't matter whether
you select to load "Configs only" or "Configs and Data". You are now ready to start
making measurements.
you select to load "Configs only" or "Configs and Data". You are now ready to start
making measurements.
For timing analysis operation above 600 MHz you need to use the ½ Channel Timing
Mode, which provides bandwidth to 1.2GHz. This mode makes every other pod
available to the user so 4 cards are required. These must be configured via the cables
supplied with the cards as a single logic analyzer module. Refer to the appropriate
Agilent Technologies manual for information on how to connect analyzer cards together
to create multi-card modules.
Mode, which provides bandwidth to 1.2GHz. This mode makes every other pod
available to the user so 4 cards are required. These must be configured via the cables
supplied with the cards as a single logic analyzer module. Refer to the appropriate
Agilent Technologies manual for information on how to connect analyzer cards together
to create multi-card modules.
Please note that 6 of the ECC bits and their Data Strobe (DQS8) are contained on an
extra Header (#14), which will require an additional logic analyzer card in order to probe.
extra Header (#14), which will require an additional logic analyzer card in order to probe.
Decoding DDR Commands
No Protocol Decoder is used for timing analysis. However, symbols are pre-defined for
the DDR2 Command bus. These decode the RAS, CAS, and WE lines to display the
DDR Command as “Read”, “Write”, etc., so you don’t have to refer to the DDR chip data
sheet to see what command is being executed. These decoded values are displayed by
setting the display base (in the listing window) or the label property (in the waveform
window) to “Symbols”. The display base defaults to hexadecimal.
the DDR2 Command bus. These decode the RAS, CAS, and WE lines to display the
DDR Command as “Read”, “Write”, etc., so you don’t have to refer to the DDR chip data
sheet to see what command is being executed. These decoded values are displayed by
setting the display base (in the listing window) or the label property (in the waveform
window) to “Symbols”. The display base defaults to hexadecimal.
Taking a Trace, Triggering, and Seeing Measurement Results
Timing analysis is the simplest setup and there are no special factors involved in
analyzer trigger setup, initiating a trace, and viewing results. For the Command bus you
can use the pre-defined symbols to specify mnemonically the command you wish to
trigger on. These are set up by default and are accessible in the trigger tab. The default
waveform display also shows DDR Commands mnemonically.
analyzer trigger setup, initiating a trace, and viewing results. For the Command bus you
can use the pre-defined symbols to specify mnemonically the command you wish to
trigger on. These are set up by default and are accessible in the trigger tab. The default
waveform display also shows DDR Commands mnemonically.
You may setup a trigger, initiate a measurement, and view results in the usual ways via
the trigger tab, pressing the Run button, and opening the desired display window.
the trigger tab, pressing the Run button, and opening the desired display window.