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Lost Configuration

mstamler , 07-30-2020, 11:12 PM
While going through the Altium Essentials course all kinds of PCB configuration was done, such as clearance figures.I am now taking the "Advanced PCB Layout" and have opened up the project for Lesson 1. To my surprise all of my configuration changes are gone resulting in violations. As an example the Design Rules/Placement/Component Clearance, which was 0.99mm is now back to the default of .254mm.
chitransh92 , 07-31-2020, 12:21 AM
You can open other PCB files in further lessons and export the Rules from that file and import in your current PCB file.

mstamler , 07-31-2020, 03:28 AM
Yes. But this should be part of the course as it makes the project less effective. Thanks for your input
robertferanec , 07-31-2020, 04:52 AM
@mstamler it should open correctly. Not all rules, as there is some incompatibility between Altium versions (e.g. differential pairs), but most of the rules should be ok.
mstamler , 07-31-2020, 06:28 AM
Hi. Thanks for your reply. It seems to me that when I open a completed reference design in Altium that the design rules for that project should be part of the project. If one loses critical design rules for, say, a high-speed reference design this can only lead to disaster. What do you think?
WhoKnewKnows , 07-31-2020, 07:32 AM
Yes, design rules should be per project. They don't survive between projects.

If you set up design rules in one project, save and close that project, then open another project, the rules (or absence of rules), are according to the newly opened project. You can close the newly opened project and re-open the previous project to see that the rules have survived. You can even have both projects open at the same time 😉 As others have said, you can export rules from one project and import them into another. This could go well, depending on how complicated the previous project's rules are. There could be variables involved, such as layer, or net names that may not apply to the new project. Good luck
mstamler , 08-01-2020, 11:48 AM
I have been using Cadence Allegro for many years. There the design rules are part of the brd project file.
the design rules are the holy of holies in PCB layout. To have them compromised because of version changes completely undermines this. So what is one to do?
WhoKnewKnows , 08-01-2020, 11:54 AM
Oh, you must want default design rules.

In Altium settings, you can nominate what to use as a default when some resource is newly instantiated.

Setting a default project file should get you the default rules you want.
robertferanec , 08-03-2020, 08:10 AM
@mstamler please try to fix the differential pair rules first to see how many other errors will be there. Altium has changed approach how differential pairs are specified in the rules. So, when you upload an older project into a new Altium, you need to add these rules. This video may help: Altium - Differential Pairs (The New & Old Way) https://youtu.be/Lb3sEcolkOA
mstamler , 08-03-2020, 12:06 PM
Thanks, I'll try it. However, many of the errors have to do with via to polygon clearances and not differential pairs.
Can you tell me which version was used in the design that is downloaded?

WhoKnewKnows , 08-03-2020, 12:16 PM
As an alternative, if you'd just like to do the lesson(s) without any distraction the drc errors might cause, you can select the error text in the message panel, right click on the message and select (the term escapes me at the moment), then that instance of that error isn't indicated as an error on the PCB (once the marker is cleared) any more. AAMOF, you can select multiple error messages and get them outta your way all at once 😉
robertferanec , 08-04-2020, 03:16 AM
However, many of the errors have to do with via to polygon clearances and not differential pairs.
I see:

Clearance Constraint (Gap=0.085mm) ((IsRegion AND (OnLayer('L2') OR OnLayer('L11')))),(All) .................................................. ......... 864
Clearance Constraint (Gap=0.075mm) ((IsRegion AND (OnLayer('L2') OR OnLayer('L11')))),(IsVia AND (HoleSize <> 0.1)) .................. 0

Hmm .. I do not really know how this is possible. I do not have the old Altium installed to check it, but this is weird. When we send data to manufacturing, there must be no errors.

You can simply fix this problem by re-building all polygons (right click on the polygon -> Polygon Actions -> Repour All), but still, that will not answer the question how this is error could happen. Good point!

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