My guess is that Arpad's question could be reformulated as follows. Do we have something in AMI spec/AMI parameters that would affect possible freedom/choice of mask parameters in the final check, compared to the case when the eye diagram is built from e.g. long Spice simulation (hypothetically) or measurement or other non-AMI related way? One possible limiter could be presence of clock ticks showing how Rx output waveform should be centered and therefore this could determine horizontal mask positioning. -----Original Message----- From: ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Mike Steinberger Sent: Tuesday, December 08, 2009 11:56 AM To: Muranyi, Arpad Cc: IBIS-ATM Subject: [ibis-macro] Re: Eye mask question Arpad- It seems to me that the timing of an Rx mask is going to depend on who defined the mask and what they had in mind when they did it. Therefore I don't think there's any one answer that fits all cases. One possibility is that the mask would be placed with respect to the clock ticks or an equivalent estimate of recovered clock timing. That choice may be appropriate for some industry standard or locally defined masks. For others, "best fit" might be the appropriate choice. Another possibility would be something related to an ideal clock recovery, such as mean or median threshold crossing time (two separate and distinct possibilities with important differences between them). In short, "Ask your mask maker." Mike S. Muranyi, Arpad wrote: > Sorry for my poor problem statement... > > I mean the output of Rx (as it comes back from > Rx GetWave), used together with the clock ticks > from Rx GetWave to formulate the eye. > > Arpad > ================================================ > > -----Original Message----- > From: Todd Westerhoff [mailto:twesterh@xxxxxxxxxx] > Sent: Tuesday, December 08, 2009 12:40 PM > To: Muranyi, Arpad > Cc: IBIS-ATM > Subject: Re: [ibis-macro] Eye mask question > > Arpad, > > Not meaning to be enigmatic here, but what signal(s) are you thinking > get used to generate the eye diagram, and how? > > Todd. > > Todd Westerhoff > VP, Software Products > SiSoft > 6 Clock Tower Place, Suite 250 > Maynard, MA 01754 > (978) 461-0449 x24 > twesterh@xxxxxxxxxx > www.sisoft.com > > > > Muranyi, Arpad wrote: > >> Hello IBIS-AMI experts, >> >> This is a question regarding the analysis/evaluation >> of the results we get back from an AMI simulation. >> >> How does the user decide whether the eye is good or bad? >> >> Naturally we have this thing called eye mask (template) >> which we would all be able to drop into the eye without >> touching any of the waveforms. But where are we trying >> to position it? Anywhere it fits the best way? Or is >> it supposed to be positioned at a certain location? >> >> Thanks for any feedback in advance, >> >> Arpad >> ========================================================= >> --------------------------------------------------------------------- >> IBIS Macro website : http://www.eda.org/pub/ibis/macromodel_wip/ >> IBIS Macro reflector: //www.freelists.org/list/ibis-macro >> To unsubscribe send an email: >> To: ibis-macro-request@xxxxxxxxxxxxx >> Subject: unsubscribe >> >> >> > --------------------------------------------------------------------- > IBIS Macro website : http://www.eda.org/pub/ibis/macromodel_wip/ > IBIS Macro reflector: //www.freelists.org/list/ibis-macro > To unsubscribe send an email: > To: ibis-macro-request@xxxxxxxxxxxxx > Subject: unsubscribe > > --------------------------------------------------------------------- IBIS Macro website : http://www.eda.org/pub/ibis/macromodel_wip/ IBIS Macro reflector: //www.freelists.org/list/ibis-macro To unsubscribe send an email: To: ibis-macro-request@xxxxxxxxxxxxx Subject: unsubscribe --------------------------------------------------------------------- IBIS Macro website : http://www.eda.org/pub/ibis/macromodel_wip/ IBIS Macro reflector: //www.freelists.org/list/ibis-macro To unsubscribe send an email: To: ibis-macro-request@xxxxxxxxxxxxx Subject: unsubscribe