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another off-grid problem (pathSeg cannot be rounded to grid)

tdtg

Here is another pesky offgrid problem. We have a design where unfortunately an instance was placed somehow by a Layout XL bug in offgrid location. Then a bunch of wiring was done with wiring and bus tools to this instance. As a result there are hundreds of wires consisting of pathSeq that are now offgrid. The vendor requires things be on 0.005um grid and these have 0.001um offgrid placements.

Now the skil script CCSputOnGridHier() will fix many of these. But we have pathSeq that cannot be fixed. We cannot even fix the offgrid manually using the property editor. If we try to adjust this vertex .691 to match the .69 Begin Point vertex, the CIW prints

*WARNING* (DB-270000): dbSetPathSegPoints: Begin and end points do not specify a horizontal, vertical, or diagonal pathSeg.

Is it because the wire is part of a bus or is somehow constrained?

This is an awful problem since we are faced with hundreds of these stupid offgrid violations and this stuff always happens right before tapeout deadline.

We would really appreciate some advice on how to proceed besides redrawing all these wires from scratch.

Thank you!

Tobi

Parents

  • I have also encountered problems in fixing "pathSeg", could you please help me upgrade the code?

  • in reply to FunnydoubleM

    Well like I said, the tens of thousands of offgrid errors resulted from a bogus offgrid placement of wiring done in a temporary copy of the top layout. When this wiring cell got placed back to the top layout it was offgrid, which should not have been allowed to occur. We did not notice and wired up lots more stuff. Now we are faced with the big job of fixing all these errors. A working offgrid fixer script would be very useful, since the current ones fail on some pathSeg wiring objects and they fail without any reporting of which ones they fail on, leaving us in a strange state of trying to find these objects by divide by two approach. Wrapping this pathSeg code in errset and reporting which objects failed (or somehow marking them) would be useful. 

    And there is still the mystery of why we cannot manually edit the pathSeg object shown above to fix it in the properties dialog. 

    It would be very nice to have a robust version of the CCSputOnGridHier script with bindkey installation to make life easier. We are not good at this coding but maybe will try it later after the tapeout.

    Thanks as always for the quick responses Andrew, you are great!

  • in reply to tdtg

     BTW, the script CCSputOnGridHier.il did this to one of our buses, shorting out a bunch of signals

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  • in reply to tdtg

    I suspect that the code has not been that well-tested with pathSegs (by the looks of things). That's why contacting support makes sense as that way the author can improve it (sorry, I'd love to re-write it, but don't have the bandwidth to do this - I'd sooner the original author improves it themselves).

    Thanks,

    Andrew

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