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Protect from wire connection on edge of hierarchical blocks

Hi all,

I find it hard to detect two pins of an hierarchical block that are connected by a wire link if the wire is placed on the edge of the hierarchical block outline. This has created faulty layouts in the past.

The picture below shows the issue where test and test2 are connected by a wire link.

Is there a way to prevent this issue (e.g. block wires on top of hierarchical blocks)? Or is there at least a better way to spot this?

Kind Regards

Martin

0 UlfK over 3 years ago

I filed an Error Report / Change Request for this problem that I also encountered years ago but the request was turned down.
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0 steve over 3 years ago

There are two DRC errors which should pick this up, the first is single node nets (electrical) and the second is hanging wires (custom DRC). In 17.4 these are both run in Online DRC mode and are showing up as a DRC for me.
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0 MartinRose over 3 years ago in reply to steve

Hi steve,

I thought the single node and hanging wire DRCs are detecting if there are missing connections. e.g. only one connection on a net or a wire ending in the air.

The problem for me is the faulty connection between test and test2 (in the red circle). Each net 'test' and 'test2' are by themselves working nets with additional circuit connected that is not shown.

Kind Regards

Martin
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0 steve over 3 years ago in reply to MartinRose

If the nets are actually shorted you could try a "report all net names" report that is part of the DRC Checks Reports Setup which should list this
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0 jc teyssier over 3 years ago in reply to MartinRose

Hello,

we already face this problem. Our workaroud:

* Use more space between pins so the "green" parts are not touching each others

* use real different colors for hierarchic block and wire so visually the wire can been seen. (exemple: ligth gray for body and red for wire)

Unfortunatly this is the only "easy" way we have found . Oher way will be to manually check the netlist but this is a big work
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