Have Board revision track the Schematic revision

warrenbrayshaw wrote on Mon, 09 January 2012 15:16

It was expressed that having the board revision match the schematic

revision

was a manual task often forgotten. Hence the board revision 'text' did

not

match the schematic revision (text).

Project attributes were suggested as a solution.

 

The desired functionality  can be achieved currently using the

attributes

features, as they are.

In use you change an attribute value in the schematic and it is

automatically corrected on the board.

 

The method:

1) By default the frame(device)  you place around the schematic

consists

only of a symbol. To this you should add a package which consists of

the

fixed text to be printed on the board, followed by a text variable

that

matches the name of an attribute we will assign latter  e.g. REV

>REVISION

2) In the frame symbol used for the device add the text variable

>REVISION

into the data area of the frame

3) In the Device editor create an attribute named REVISION, value 0.0,

variable, all.

 

To update the revision text in the Frame data area and on the board all

that

is required is to change the value of the REVISION attribute of the

frame

(select frame origin, lower left corner usually)

 

This technique revealed to me a feature of frames. Performing a

"Library

update all", in the schematic editor, does not update the frame.

Further

investigation required to see if this is documented behaviour.

I had to delete the current frame and re-add the frame.

Hi Warren,

Not a bad idea.  I haven't tried it but it should work.  Downside is that

the text size can't be changed so you might need multiple footprints for

different sized text--a bit of a kludge.

The issue with updating the library has nothing to do with the frame.  When

you update a library the value of a device is not updated in the schematic.

I would like to see a dialog that asks what you want to do in this case.

Right now, it just ignores value updates.  My general rule of thumb is that

values are stored in the library and so I normally want to overwrite the

schematic with the value from the library.

I would propose a dialog with the standard options:

1)  leave value as is in the schematic

2)  update value from library

and a check box to choose the same option for all remaining questions.

That gives us the same functionality as previously with some added

flexibility.

I still think having the tool recognize "global variables" in a global

fashion is a better way to go.  We still should have the enhanced update in

any case.

Cheers,

James.

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On it's surface, this isn't a terrible workaround.  The downside comes in when you have multiple sheets in the schematic - each with it's own frame object with independent attributes that needs to be individually changed.  There are then also the multiple text objects in the PCB to be dealt with.  Yes, the multiple copies can be hidden but now you are back to the case where it is much less of a hassle to keep a global attribute in both schematic and pcb and take your chances with out-of-sync attributes.

I still think having the tool recognize "global variables" in a global

fashion is a better way to go.  We still should have the enhanced update in

any case.

I echo this sentiment!

On it's surface, this isn't a terrible workaround.  The downside comes in when you have multiple sheets in the schematic - each with it's own frame object with independent attributes that needs to be individually changed.  There are then also the multiple text objects in the PCB to be dealt with.  Yes, the multiple copies can be hidden but now you are back to the case where it is much less of a hassle to keep a global attribute in both schematic and pcb and take your chances with out-of-sync attributes.

I still think having the tool recognize "global variables" in a global

fashion is a better way to go.  We still should have the enhanced update in

any case.

I echo this sentiment!