vRestrict layer and DRC

Am 16.03.2011 00:16, schrieb Bob Johnson:

I have a 4-layer board originally routed in Eagle V4 (Linux/Pro) that passed

ERC/DRC and went to production. It was discovered later that a connector had

issues (shorts) with vias under it. I'm now correcting that in V5.11.0

(Linux/Pro). I edited the connector symbol to include a vRestrict layer and

did a Library-Update All. The connector updated correctly and the vRestrict

layer now shows up as expected. Curiously, though, when I run DRC no errors

are flagged, even though nothing on the board changed except the connector

and the vias are still there, now clearly underneath the vRestrict layer.

 

I did a newsgroup search and the only possibility I saw was an issue with

blind vias. My stackup, however, is a simple (18+916) with no blind vias

defined. Is there some other setting I might be missing, or have I just run

into an Eagle bug?

Please read manual_en.pdf; page 148 == vRestrict:

Layer 43, vRestrict, is for drawing restricted areas where the

Autorouter or the Followme router may not set vias. Manually placed

vias in such a vRestrict region are not examined by the DRC and

therefore not reported as an error.

Mit freundlichen Grüßen / Best regards

Alfred Zaffran

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"A. Zaffran" <alf@cadsoft.de> wrote in message

news:ilpm2b$5tf$1@cheetah.cadsoft.de...

Layer 43, vRestrict, is for drawing restricted areas where the

Autorouter or the Followme router may not set vias. Manually placed

vias in such a vRestrict region are not examined by the DRC and

therefore not reported as an error.

Interesting. I wasn't aware of this. Are there any reasons for this

behaviour? I would expect the DRC to warn about vias in vRestrict area.

Am 16.03.2011 08:53, schrieb Morten Leikvoll:

"A. Zaffran" <alf@cadsoft.de> wrote in message

news:ilpm2b$5tf$1@cheetah.cadsoft.de...

>> Layer 43, vRestrict, is for drawing restricted areas where the

>> Autorouter or the Followme router may not set vias. Manually placed

>> vias in such a vRestrict region are not examined by the DRC and

>> therefore not reported as an error.

 

Interesting. I wasn't aware of this. Are there any reasons for this

behaviour? I would expect the DRC to warn about vias in vRestrict area.

Let's call them historic reasons.   Initally we wanted to have a

possibitlity to tell the autorouter where it is not allowed to set

vias. There was no DRC available at that times. The function of the

vRestrict layer remained unchanged.

--

Mit freundlichen Gruessen / Best regards

Richard Hammerl

CadSoft Support -- hotline@cadsoft.de

FAQ: http://www.cadsoft.de/faq.htm

"Richard Hammerl" <ric@cadsoft.de> wrote in message

news:ilprsf$1us$1@cheetah.cadsoft.de...

Am 16.03.2011 08:53, schrieb Morten Leikvoll:

>> "A. Zaffran" <alf@cadsoft.de> wrote in message

>> news:ilpm2b$5tf$1@cheetah.cadsoft.de...

>>> Layer 43, vRestrict, is for drawing restricted areas where the

>>> Autorouter or the Followme router may not set vias. Manually placed

>>> vias in such a vRestrict region are not examined by the DRC and

>>> therefore not reported as an error.

>>

>> Interesting. I wasn't aware of this. Are there any reasons for this

>> behaviour? I would expect the DRC to warn about vias in vRestrict area.

 

Let's call them historic reasons.   Initally we wanted to have a

possibitlity to tell the autorouter where it is not allowed to set

vias. There was no DRC available at that times. The function of the

vRestrict layer remained unchanged.

I assume there is a secret point in the secret todo list to change this then

Am 16.03.2011 09:32, schrieb Morten Leikvoll:

"Richard Hammerl"<ric@cadsoft.de>  wrote in message

news:ilprsf$1us$1@cheetah.cadsoft.de...

>> Am 16.03.2011 08:53, schrieb Morten Leikvoll:

>>> "A. Zaffran"<alf@cadsoft.de>  wrote in message

>>> news:ilpm2b$5tf$1@cheetah.cadsoft.de...

>>>> Layer 43, vRestrict, is for drawing restricted areas where the

>>>> Autorouter or the Followme router may not set vias. Manually placed

>>>> vias in such a vRestrict region are not examined by the DRC and

>>>> therefore not reported as an error.

>>>

>>> Interesting. I wasn't aware of this. Are there any reasons for this

>>> behaviour? I would expect the DRC to warn about vias in vRestrict area.

>>

>> Let's call them historic reasons.   Initally we wanted to have a

>> possibitlity to tell the autorouter where it is not allowed to set

>> vias. There was no DRC available at that times. The function of the

>> vRestrict layer remained unchanged.

 

I assume there is a secret point in the secret todo list to change this then

 

>

I will forward this to our development people.

--

Mit freundlichen Gruessen / Best regards

Richard Hammerl

  CadSoft Support -- hotline@cadsoft.de

  FAQ: http://www.cadsoft.de/faq.htm

>> Let's call them historic reasons.   Initally we wanted to have a

>> possibitlity to tell the autorouter where it is not allowed to set

>> vias. There was no DRC available at that times. The function of the

>> vRestrict layer remained unchanged.

 

I assume there is a secret point in the secret todo list to change this then

 

>

I found this posting from four years ago after I'd noticed the same thing - I had a via in a vRestrict area, and was surprised that the DRC hadn't picked it up.

If there's concern about breaking old board designs, perhaps a new layer (reallyVRestrict) could be introduced. Or even rename layer 43 to something other than vRestrict whenever it is found in a board file, and allocate the name vRestrict to a new layer number that behaves like the other restrict layer types.

>> Let's call them historic reasons.   Initally we wanted to have a

>> possibitlity to tell the autorouter where it is not allowed to set

>> vias. There was no DRC available at that times. The function of the

>> vRestrict layer remained unchanged.

 

I assume there is a secret point in the secret todo list to change this then

 

>

I found this posting from four years ago after I'd noticed the same thing - I had a via in a vRestrict area, and was surprised that the DRC hadn't picked it up.

If there's concern about breaking old board designs, perhaps a new layer (reallyVRestrict) could be introduced. Or even rename layer 43 to something other than vRestrict whenever it is found in a board file, and allocate the name vRestrict to a new layer number that behaves like the other restrict layer types.