I am working on a design where a FPGA needs to be connected to a DAC using LVDS lines:
How do I define the bus members in this case correctly (if at all possible)?
You are using suffixes P and N and that should work. But buses are a bit finicky in KiCad.
In your case you have given the name “BUS” to your bus, and as a result, each member of the bus will have the BUS prefix with a dot.
So DATACLKP is not a member of your bus, but it’s name is: BUS.DATACLKP
The P and N suffixes also do not get added magically to bus names. BUS.D2 is a member of your bus. You can use the Unfold from Bus function with a right click on the bus to see what the members of your bus are:
As you can see, the [0…11] are expanded to 11 bus members, but this does not seem to work with the post-fixes for differential pairs. Worst case you have to spell them all out in an alias list in Schematic Editor / File / Schematic Setup / Project / Bus Alias Definitions
It is indeed unsupported. There is an open feature request for a list of differential pairs on gitlab, and you can give it a thumbsup:
In the mean time, I guess your only option is to work with an alias list and spell all the names out completely.
thanks for suggesting the Bus Alias Definitions. The user interface does not support copying busses (I have several similar busses in my design) but that can be easily done using a text editor.
I upvoted the isse on gitlab. hoping to see this implemented in the future.
If you have several busses, with a lot of similarly name, you can re-use the alias list in different buses. You don’t have to copy all the individual members between the buses.
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good to know, thanks!