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How to use ViVA to calculate digital bus from AMS simulation output?

greatqs

The purpose is to use Skill or OCEAN to post-processing AMS simulation (by irun) output waveform and do some auto-checks on signals in digital domain.

I'd like to use "cross" function in ViVA calculator to find specific time at digital event transition. I tried that it works fine for single bit digital signal. However, it cannot work for multi-bit vectors.    

For example, if I use below expressions, the calculator will say "expression evaluation failed"

cross(awvDigital2Analog(getData("tb.DUT.u_DTOP.u_digital_top.D2A_FREQ_SEL[2:0]" ?result "tran-tran-2")) 0.5 1 "rising" nil nil  )

cross(getData("tb.DUT.u_DTOP.u_digital_top.D2A_FREQ_SEL[2:0]" ?result "tran-tran-2") 0.5 1 "rising" nil nil  )

 

Besides, it also seems that the "real" variables are treated like "interpolated lines" and although ViVA shows sharp transition, the "value" or "cross" calculator functions actually returns the "interpolated results". For example, a real variable A transition from 0 to 1 at 1ms. Function "value(getData("A") 0.5ms)" returns 0.5 instead of 0.

Are there any methods to workaround these 2 issues?

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