Removing P&R boundary

Hi,

first it should be noted that it is dangerous to remove the prBoundary because it is a fundamental requirement for designs on OA.

Any OA based tool may have issues (crashes even?) if this does not exist.

Having said that. It is possible that existing Cadence tools may still work correctly without a prBoundary.

The prBoundary is normally displayed using the LPP prBoundary/boundary. You will need to make this selectable by setting the layer "valid" in the layer palette.

Click RMB "edit valid layers" and you will probably see that it is not set "valid".

Colin

I don't believe a prBoundary is required in OA. Many designs would not have this. It does tend to be required by placement or routing tools because they need to know where the placement and routing must be bounded within.

In OpenAccess it's not a shape on a layer - and so setting the validity of an LPP doesn't make any sense. Instead you can either use the Objects assistant (related to the Layer Palette), find the "Boundaries" section, and turn on the selectabilty of P&R Boundary.

Or on VLS XL, you can do Right Mouse->Make PR Boundary Selectable over the layout canvas somewhere.

Regards,

Andrew.

One last comment.

You may experience problems if you try to use the Wire Editor, placers or routers without a prBoundary. They all require the prBoundary and, depending on the exact software version you are using, you may get some "unexpected" results.

Indeed - interactive routing with the wire editor will work fine without this, but if you use the automatic features such as finish wire, then it will fail because these require a boundary to constrain the routing.

So the recommendation with VLS XL would be to retain the prBoundary to allow you to take advantage of the automated features. It's not particularly onerous to keep it, after all.

Regards,

Andrew.

Thanks for the heads up. For this design, I won't be using the automatic place and route tools but I'll keep your comments in mind. Probably best I just set the PR boundary to non-visible. It's just that the color looks very close to one of our layers and everyone is already used to the color set so I didn't want to change the colors around unless I can change the PR boundary color? But I haven't seen an option for that in the objects palette and I assume the Display Resource Editor doesn't change such objects(?).

Another comment about the prBoundary

The LPP prBoundary/boundary is used for defining how the prBoundary object is displayed.

So you can define how the colors look by using the Display Resource Editor

This is sometimes a cause of confusion. There should never be any geometric shapes on this layer.

Drawing a rectangle/polygon  on layer prBoundary/boundary is not the same as creating a prBoundary (create.>p+r objects).

The lpp is only there for display/selectability reasons, (although selectability can be controlled by other means, as Andrew stated)

 One other comment.

I have just re-tested the routing/Wire Editor features in 6.1.6 (including DRD enforce mode) and it does, indeed, seem to work fine without a prBoundary.

This was not the case in earlier versions of the software (6.1.5)

But anyway, I would suggest keeping the prBoundary in. It may prevent problems further down-stream.

The color is determined via the packet for the prBoundary/boundary layer-purpose pair. So if you bring up the display resource editor, search via layers (All) and search for prBoundary, you'll find prBoundary/boundary.

Whilst the object itself is not a shape on a layer-purpose pair, the colors are picked via packets associated with layer purpose pairs - as it's really the only mechanism for associating packets.

Regards,

Andrew.