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FS2331 Calibration
The FS2331 is calibrated for operation at DDR333 rates, this should be sufficient for it’s
operation. In the event that Data eye closure is seen during Eyefinder or Eyescan of
simultaneous Writes and Reads, then the FS2331 calibration may need adjustment. The
procedure below outlines this process.
If capture of both read and write bursts is required in a single measurement then special
circuitry on the probe that deals with the different timing of read and write bursts must be
checked. Depending on the results, the FS2331 must be calibrated along with setting
the analyzer sample position. This specialized circuitry compensates for the differences
in read and write timing by delaying the DQS0 strobe for reads. This ensures the data is
stable (relative to the analyzer clock) at the same time for reads and writes. Use the
following steps to determine if calibration steps are necessary for your application
(probe, system board, and DIMM module).
To perform this check you should set the probe configuration switch (SW-6, On) to clock
both read and write bursts to the analyzer, start your stimulus (that contains frequent
read and write bursts) , and run Eye Finder. Below is a typical display