BUG: Drawing path in Virtuoso 6.1.6 only possible in routing layers

Hi Sjoerd,

The create path command should work as you expect.

Is it possible that you are confusing the create path with the create wire command?

The create wire command (often invoked with the "p" or "P" bindkey) does require routing layers. The routing layers are defined in the tech file and constraint groups.

But the create path command: create->shape->path should work with any layer.

From your description I believe you are trying to use the create wire command.

Regards

Colin

Hi Colin,

You are spot-on, and you just posted your reply a bit soner then I had time to update this post.

What has happened:

The bindkey "p" in 6.1.5 was used to create a path. In 6.1.6 it has been changed to create a wire.

The solution:

I re-mapped the bindkey for "p" back to creating a path. Creating a wire is now available with the "w" key (no-one used the zoom-history function of the "w" hey anyway).

So yes, luckily, Cadence just  changed the behavior of the bindkey, not the actual function of the path creating procedure.

Thanks for your response.

With kind regards,

Sjoerd

Hi Sjoerd,

I'm not sure that's what I'd recommend doing. The most common usage for paths is for creating routing - and there is a significant benefit in using create wire for this. There's so much "muscle memory" in the "p" bind key that we found that even though people were aware of create wire, they persisted in creating paths. Also some who weren't aware of create wire completely bypassed it.

What I'd suggest is creating a different bind key for creating paths, and leave the "p" as the (now) standard for creating routing,

Regards,

Andrew.

Hi Andrew,

I understand why Cadence changed the bindkey, however, I do not agree with it.

The same arguments you're putting forward can be used to defend the opposite. Since the "p" key is "hard-wired" into out brains, just changing the behavior will meet a lot of resistance, at least from my colleagues. Furthermore, a path is not always a wire, but a wire is always a path (wire is sub-set of path). Creating a wire in stead of a path has its advantages, but some big disadvantages as well (it limits your freedom to do whatever you like).

Per the request of my colleagues, I have assigned the "p" key to creating paths, and the "w" key to creating wires. In a few weeks time I will ask them how often they have used the "w" key (wires), and I might revert the "w" key back to it's original binding if not used that often (since I use the "w" key a lot). By the way, all of my colleagues know about the existence of the "create wire" functionality and know its pro's and con's.

Kind regards,

Sjoerd

Hi Sjoerd,

I just want to correct part of your text.

Wires do not contain paths anymore. Wires contain pathSegs and vias

In earlier versions (IC615) Wires contained either paths or pathsegs. Wires containing paths were called (geometric wires).

In any case, wires are not subsets of paths or pathsegs.

FYI, using wires  will guarantee that any 45 geometries will create on-grid coordinates. That is not the case with paths.

Also, wires are compatible with the auto routing tools, paths aren't.

So my recommendation: use wires for interconnect.

Colin