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  3. Rats not visible while placing component.

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Rats not visible while placing component.

EnottonE
EnottonE over 3 years ago

The problem is as follows: after installing the 019 hotfix, the rats were no longer displayed when placing the component. After installing the component on the board, the rats are displayed, but until it is installed, it is not clear what elements it is associated with, this is very inconvenient. All rats display settings are enabled (RatsOn), in the constant manager in the chain properties, the No Rats property is disabled for all chains. What other settings can I see for displaying Rats when placing the component?

During the placement of the component:

After placing the component:

Has anyone had similar problems? (20 hotfixes did not help :( )

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  • excellon1
    excellon1 over 3 years ago

    So normal operation would be as follows and has been this way forever on previous versions of Allegro.

    With Black Rats All "Enabled" so that all rats on the board are turned off and placing a new component the rat lines should show up when the component is picked and is on the end of your cursor so you
    can move it around to place it, Provided a net on that particular component also exists on the board. If you place this component outside your board outline as in your picture the rat lines wont show
    because rats are disabled.

    If show rats all is enabled so all nets are shown and you go about placing a component as above the rat lines will show & when you place the component outside the board outline the rats will also show
    provided a net associated with the new part does exist on the board.

    So when that part is ready for placement and on the end of your cursor regardless if the rats are on or off the rat line is meant to show up. If not it is broken !

    Will check 17.4 & let you know.

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  • excellon1
    excellon1 over 3 years ago in reply to excellon1

    Just a follow up. I had someone check S020 & the rat line does not display when a part is on the end of the cursor ready for placement as it used to do.

    In S020 "THIS IS BROKEN" - Does not work.

    Just a note on this. There is a possible use case if someone has a high pin count part such as a BGA and they decide to place that later on in the design. In such a case 
    and if components did exist on the board then you would end up showing alot of ratlines during placement so not showing them during placement might be good in that case only !.

    It could be somewhere someone had requested this as a feature and it would make sense on high pin count device but at the expense of other users. Believe what is needed is a
    user preference something like this.

    Disable rat lines during placement. This would keep things as they are now in consideration of high pin-count parts only. "Its a bit of a red herring to be honest" as usually those high
    pin count parts get placed "First"

    Either way as it is right now the expected operation is not in concert with previous releases. V17.2 & 16.6 do not have this issue. From your post it looks like from 17.4 S019 on this is broken.

    One last thing. The display of the rat lines during placement only works if parts exist on the board that would have a net associated with the part getting placed or getting moved around at that time
    during placement.

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  • EnottonE
    EnottonE over 3 years ago in reply to excellon1

    I will probably have to roll back to the 018 fix

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