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Cadence Virtuoso: Import a large verilog netlist to cadence schematic

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oAwad

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Hello all,

I imported a verilog netlist for a layout previously designed in Encounter. When I try to open the schematic and hit check&save, I get these errors:

Error: Net "v_CALCULATION_CNTR<7:0>" shorted to net "N5512,N5511,N5510,N5509,N5508,N5507,N5506,SYNOPSYS_UNCONNECTED__0".
Error: (DB-270004): Illegal bus reference - Can't tap "<N5507>" from net "v_CALCULATION_CNTR<7:0>".
Error: (DB-270004): Illegal bus reference - Can't tap "<N5512>" from net "v_CALCULATION_CNTR<7:0>".
Error: (DB-270004): Illegal bus reference - Can't tap "<N5509>" from net "v_CALCULATION_CNTR<7:0>".
Error: (DB-270004): Illegal bus reference - Can't tap "<N5508>" from net "v_CALCULATION_CNTR<7:0>".
Error: (DB-270004): Illegal bus reference - Can't tap "<N5511>" from net "v_CALCULATION_CNTR<7:0>".
Error: (DB-270004): Illegal bus reference - Can't tap "<N5510>" from net "v_CALCULATION_CNTR<7:0>".
Error: (DB-270004): Illegal bus reference - Can't tap "<N5506>" from net "v_CALCULATION_CNTR<7:0>".
INFO (SCH-1172): There were 8 errors and 0 warnings found in "NangateOpenCellLibrary key_expansion_KEY_SIZE0 schematic".

Moreover, I can see lots of unconnected wires like the attached picture

cadence.PNG

This verilog netlist was exported from SoC Encounter from a layout with no geometry or connectivity violations.

Any suggestions ?

EDIT: the unconnected wires are probably due to some floating output pins of std cells that are not used in the design and I don't see errors complaining about them.
 
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I tried this once and got an unreadable pile of symbols
connected by named nets, in such disarray that it made
no sense at all to "eyeball" inspection.

It's possible that the process of conversion, or some
"oops!", laid a solder dot onto a bus segment and
shorted it all. I recommend finding one such segment,
probe it and inspect for this kind of "forced error".

Useless tool, last I left it.
 

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