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alegro reuse module -how to - need advice for lc layour artist

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Junior Member level 1
Feb 2, 2011
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I am trying to make a reuse cell in alegro pcb and am having a heckof a time.
here is what I have done:
I made the schematic for the module
export net list (forcing it to create the module when I sink them)
Made the module layout
mad the module form the layout.

instantiated the module in a schematic.
exported the net list (design synk) exporter to use and force use of the module.

now when I place the modules I get drc erros saying that the nets are shorted and all the pads are on undefined nets... It is acting like it forgets all of the nets in the modules. also the refdes's in the modules are the same that is they are missing the _indedx of reuse module.

Any help on the subject would be much appreciated.

I find it very difficult use reuse modules in alegro all most to the point of it may bee easer and faster to do one flat schematic 10 to 20 pages and lay each part out by hand. My background is in IC layout in virtuoso where if you need the equivalent of a "reuse module" you just make a schematic and layout and drop it in done end of story no fuss, no buss and their is not 20 steps to crate a module...

Solve - With a lot of gotchas!
to solve this problem only mark force or use not both. If that does not work reenlist export and then generate the module layout.
Below is a list of gotcha shortcomings I have found with allegro pcb modules:
-gotcha #1 - when using modules in allegro you can not mirror them! That is if you want to flip a layout around to the back side of the board you must make a new module relay it out with the parts and traces on the other side of the board.
-gotcha #2 - fixed property is inhabited from the module to the top level of the design. Unlike in virtuoso properties set in a sub design apeer at the top level.
- along same lines modules are modifiable at top level not rigidly set. This can be problematic see #3.
-gotcha #3 - to move or rotate a module you must create a temp group which contains the module in order to move it.

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