Does the autorouter work with a double sided board in Ultiboard Education Edition?

[KevinSmith]

When I set Layer pairs = 1 and Stack-ups = 0 under PCB Properties | Copper layers, I get the error message “Ultiboard Error during autorouter preprocessing. Invalid via definition - must be multiple layers and circular”. 

However, if I set Layer pairs = 2 and Stack-ups = 0, the autorouter works just fine.

Is there a way to get the autorouter to work with a simple double sided board?

[Tien_P]

Hi Kevin,

With the layer pair set to 1, you should be able to route on top/bottom layer.  Have a look at this knowledge base and see if it applies to you:

http://digital.ni.com/public.nsf/allkb/7A814AD0411858BD862575E80037EC51

I don't know why you are getting that error message with the via definition.  Can you post a file with the problem?  I don't need a complete design, delete all the crucial parts on the layout just leave a few parts so that I can autorouter and see where this error is coming from.

[Tayyab_R]

Hi Kevin,

Is should not be an issue to route on a simple 2 layer board using the autorouter. Can you send us your files so we can see what could be causing the issue.

[KevinSmith]

I found the following work around to the error when trying to autoroute a double sided board.  Can someone explain why this worked?

To autoroute a double sided board (with error work around):

1. Open Options | PCB Properties | Copper layers and set the following:

• • Layer pairs = 1
  • Single layer stack-up: Top = 0 and Bottom = 0
  • Set copper top routing: Allow routing | Copper Top | Copper layer: Properties | select Routing
  • Set copper bottom routing: Allow routing | Copper Bottom | Copper layer: Properties | select Routing
  • Select OK
• Select Autoroute | Start/resume autorouter

• Do the following if you get the error “Ultiboard Error during autorouter preprocessing. Invalid via definition - must be multiple layers and circular”
• Disallow routing on EITHER the top or bottom copper layer
• To unset copper top routing: Allow routing | Copper Top | Copper layer: Properties | unselect Routing
• To unset copper bottom routing: Allow routing | Copper Bottom | Copper layer: Properties | unselect Routing
• Select Autoroute | Start/resume autorouter
• Immediately select Autoroute | Stop/pause autorouter
• Allow routing on both the top and bottom copper layer
• Select Autoroute | Start/resume autorouter
• The board now autoroutes without the error noted above.

[Tien_P]

Hi Kevin,

If you select Options>>PCB Properties>>Copper Layer, increase you layer part to 2, now under Via Support uncheck the "Blind via" checkbox.  Change the layer pair back to 1 and this should fix the router problem.

Ultiboard should recognize that a two layer does not support blind via and the blind via support shoulb be ignored, so I will let R&D know about this issue.