Hierarchical schematics

I created a project at work that consisted of a Processor bd, an Interconnect bd and one to 8 Interface board.
The Interface board is the same and just plugs into the Interconnect board and is uniquely addressed using SPI.
I created a Hierarchical project in KiCad with the top level showing the Processor, Interconnect and 8 Interface boards. The Processor, Interconnect Interface boards each had their own schematic sheet.
I next tried to run DRC but got errors of multiple U1, etc because each board had it’s own annotations.
I tried to fine some way for the DRC to only check the current schematic as I want to make separate PCBs.

I think there is no way to do this in KiCad. Am I missing something? I know Hierarchical schematics are use full for complex PBCs where it would be helpful to break the schematic into logical blocks. But it would also be helpful to make each schematic in a Hierarchical design it’s own PCB.
OtG

The “philosophy” of KiCad is one schematic -> one PCB.
So, create 3 projects for 3 boards.
I do this way since “beginning of time” (from DOS era - sMartwork, Tango, … ) :smile:

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ZASto is right in that the official viewpoint is that each PCB has it’s own project, but there are a few things you can do.

If you have a recurring design such as add-on cards you make a template from it, which makes it a bit easier to re-use PCB outline, connector and mounting hole layout and other features.

Some time ago I did an experiment with a multi-pcb project and it seemed to work pretty well. Several others have also used this method and also seemed to like it.

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Are you making 3 different boards? When you order boards you get one Processor board, one Interconnect board and eight Interface boards? Why only one schematic? Why not three? I would have 3 schematics and 3 PCBs plus a top level schematic that calls out 3 schematics and a note on the schematic (repeat 8 times). Then run error checking on the top level board if you feel you need to.

In my case I make a large board because of price. The board then breaks down to 1-P, 1-Inter, and 8 IO boards. “P” board has R1 through R99, “Inter” has R900 through R999 and “IO-1” has R100 through R199, IO-2 has R200 through R299,…IO-8 has R800-R899. In my case the Pick and Place machines can not handle R100 on eight different sub boards.

I think we are doing very different things. (maybe the inverse)

Yes making one Processor and one Interconnect PCB. Also Making 8 Interface boards but they are all the same, so in essence it is one PCB, but ordering 8 copies.

Only one schematic to document the entire project. I made the hierarchical schematic first, then realized I could make separate PCBs. I did have to create three new projects, a real pain.

Yes, we are doing inverse. The current capabilities of KiCad lend itself to making ONE, complex PCB and using a hierarchical schematic to create it. Important and probably used more than my requirement but I think both should be supported somehow. Just IMHO.
OtG

Will study this and see how it works, thanks.
OtG

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