Copper zone priorities in "How to create a power plane" (The FAQ)

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I think this is a really good FAQ but I feel there is one simple/important omission (unless I missed it.)

Regarding power plane (zone) priorities: I had assigned a priority number 9 (and then later I tried 2) to my ground plane, but I found that this priority 9 ground plane overwhelmed a couple of small signal planes which were assigned priority 1. I am using a recent nightly and was preparing to file a bug. But as the last thing I did before filing the bug: I tried swapping these priority assignments. Doing this took care of the issue. I don’t think it is a big problem but in common English I think of priority 1 as being top priority. With zones (planes) in KiCad the higher number seems to take priority. I feel that this ought to be mentioned somewhere in that FAQ.

Application: KiCad
Version: (5.99.0-1124-gd78759612), release build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.66.0 OpenSSL/1.1.1d (Schannel) zlib/1.2.11 brotli/1.0.7 libidn2/2.2.0 libpsl/0.21.0 (+libidn2/2.1.1) nghttp2/1.39.2
Platform: Windows 8 (build 9200), 64-bit edition, 64 bit, Little endian, wxMSW
Build Info:
    Build date: Mar 18 2020 21:58:56
    wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8)
    Boost: 1.71.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.66.0
    Compiler: GCC 9.2.0 with C++ ABI 1013

Build settings:
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=OFF
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON
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I think the ‘hint’ here is that the default value will be low.

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I was not sure if the 0 default was a special class. With many parameters, a 0 does something unique. It seems that there are many things in life which are easy until I get exposed to the opposite, and then it gets confusing as heck. “To table a discussion” I think has opposite meanings in UK and USA. That sort of makes it a useless term and now I never know what it means. In this case I suspect that many users might be baffled for a few minutes until they figure it out. I think that including this tidbit in the FAQ would spare many users some minutes each; more if they need to re-assign the priority of a bunch of zones.

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The FAQ is in WIKI format. I’m not sure what level you need to be to edit it. Could you give it a try?

The reason I quoted ‘hint’ is because different people can have different ideas so changing it would just confuse the other half. :wink:

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I will see…I doubt that I have permission to edit the FAQ. I would not want to change the software; only to add 1-2 sentences to the FAQ.

A couple of minutes later…I believe I have confirmed that I cannot edit the FAQ. That is OK; I doubt that my KiCad skill level is up to that.

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I changed it now. …

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I agree that knowing which is a higher priority can be confusing, however there is a helpful tooltip to remind you if you hover over the text.

Screen Shot 2020-03-20 at 14.18.59

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Thank you, John. For me, tooltips seem to be out of sight and out of mind. Until you mentioned it now, I did not know that there was a tooltip there.

Thanks a lot, Eeli

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This is a case where one person sees KiCAD’s behavior as a “charming idiosyncrasy” but another person sees a “frustrating quirk”. It begins with the fact (as @BobZ mentioned in the initial post ) that North American English is ambiguous about the meaning of “priority level”. Or at least, the meaning in vernacular English is in conflict with the meaning implied by mathematics. In a mathematical sense, “Priority Level 3” would be expected to take precedence over “Priority Level 2” because 3 is a larger (more positive) value than 2; in our commonplace language, “Priority 3” (as in, "My third priority . . . ") would likely not be considered until after “Priority 2” was satisfied. Other cultures may perceive this situation differently.

Because of this cultural ambiguity I would construct examples using specific numerical values when I wrote text for “Tool Tips” or “Help” files. Perhaps something like,

  • For example, a Level 3 zone will be filled before a Level 2 zone. When the Level 2 zone is filled, the fill will respect the Level 3 zone already completed.
  • If a Level 2 zone is completely enclosed within a Level 3 zone, the Level 2 zone is effectively removed from consideration.
  • If two zones of the SAME priority (and different nets) intersect, the result is uncertain and may change from one “Fill” operation to the next.
  • If a zone completely encloses a zone of the SAME priority (and different net), a DRC error is set.

You have too much experience in a technical world. To prevent us superannuated geezers from over-thinking this situation, perhaps the esteemed KiCAD Developers should limit zone priority levels from “1” to “100” instead of “0” to “100”. (But still respect the “0” value as a lower priority than “1”, to retain compatibility with existing projects.) Or perhaps they will maintain the status quo and giggle gleefully when they observe our frustration.

Or perhaps this will be added to the trove of folk wisdom shared among the KiCAD cognoscenti. In the same class as,

Those of us who have done more than a handful boards create and maintain our own personal libraries.

We would say,

Experienced users assign zone priorities from “1” to “100”, but usually reserve “Priority 0” for a ground plane zone that encloses the entire board. This zone will fill in the leftover areas after all the other zones are filled.

Dale

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Hi, dchisholm

Often times, a statement seems humorous because it is true. Your comment above gave me a good laugh. But I do think that Eelik’s addition to the FAQ clears my concern.

I just wonder if I am the only one who seldom (if ever) thinks to look for tool tips…

Added later:

This part sounds particularly helpful.

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The software is probably designed with defaults that make the erroneous assumption that ‘activity equals knowledge and trust’ which is not particularly applicable to this community. I seem to remember that you can actually drop a level or two through inactivity. Still, I really think that this software has many positives.

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Regarding “software” I am not certain whether you are referring to KiCad or the forum software. Anyway I am not complaining about either…just requesting that an ambiguity be disambiguated. If we do too much to revise the forum we will have to bump it up to a fivum.

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I got a good chuckle out of this. Since I quoted about the FAQ I ass u me d it was obvious. (OK. Looking at this many non native readers may not get the reference. Assume makes an ass of u (you) and me) Kinda like the priority level thing. :smiley:

Mainly I was surprised that for as much as I see you posting you didn’t have the level required to edit the FAQ yourself.

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I think there are plenty of examples…especially nowadays…of people who speak a lot but say very little that is trustworthy. Some of these people are in high office.

If you are a mathematics instructor who wants to test a new mathematics course, you should not limit your testing to fellow math instructors. It is best to include a lot of ignorant students. I often take a different spin on things, and I see myself as more the ignorant student. I have been doing analog/power circuit design for my entire adult life so I am not referring to that. But as an old geezer who is no software expert, I am likely to fall into holes that some people more software-oriented are likely to avoid. So I think I may have some value as a tester of the nightly release versions. It surprises me how many people on this forum are seriously into Linux and other open sourced software; I have no experience with any of that. I get lost with “environment variables” etc. but I do know what a good pcb layout looks like for a power converter.

Then there is the old comedy line about not being willing to join any club which is sufficiently low grade to accept me as a member. I am glad that the moderators of this forum recognize that I should not be trusted to edit an FAQ. It raises their level of respect in my eyes.

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There has probably never been much correlation between the amount of noise someone produces and his intelligence and intentions. Nothing new here. In program speak it’s called a “babbling idiot”
https://duckduckgo.com/html?q=“babbling+idiot”

About the forum:
I never looked deep into it. Absolute beginners do not to upload too much untill they’ve accumulated about 30 minutes worth of “viewing time” which seems a sensible anti -spam measure which is unfortunately necessary in this world, and saves moderator a lot of time, because there are 4000+ users here.

When it gets to important tasks (Becoming a moderator, making FAQ’s) I guess these are only by manual intervention by a real person. So my guess is that if you want such rights you have to ask for it to someone who can give you such rights.
Some more about the forum rules here:
https://forum.kicad.info/faq

And the first link on that page links to https://www.discourse.org/ which is apparently the name of this forum software.

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I think the trendline would probably have a negative slope.

Actually I think this forum software works pretty well. If I have one complaint, it is too much dependence on icons. I recognize that icons avoid language issues, but we are discussing in English. But as a monolingual English speaker, I think it would be easier for me to use buttons which are labeled in German than to use buttons labeled with icons.

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