Sending bus between sheets

Schematic
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I’m trying to move a CPU’s address and data busses from the parent sheet (where the CPU is) to a child sheet, which has the address decoding logic. If I use individual signals, everything works, but if I connect a bus to a hierarchical pin or global label, the nets don’t connect.

I’ve seen various questions about this, but haven’t found a clear response or solution which works for me.

I made a simplified example which shows the problem. The schematic is nonsensical, it’s just to show the issue.

Here’s are the sheets. I had to squash parent and child into a single image.
I’ve put the outputs of this '74 on a bus, and connected it to the second unit of the same part via a bus; also, sent both OUT1 and the whole bus to the child sheet.

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The child sheet pulls OUT0 from OB, and connects OUT1 directly. The latter connects fine, but the former does not connect at all.

I have tried:

  • Creating a local label for the bus on each sheet. I found some people saying this was necessary for the signals to connect. It doesn’t work for me.
  • Connecting the bus directly to the sub-sheet, versus using a local label in the parent sheet. This also doesn’t work.
  • Changing the label to be a common prefix for all the lines on the bus. ex. for lines A[0…15], the bus label is A. This does not work.
  • Using a global labels instead of hierarchical. I prefer not to use this approach, since I’d rather see the connections between sheets; however, this inexplicably also doesn’t work.

I’m baffled that this doesn’t appear to work at all. Is there any way to send a bus to a sheet?

I’m using KiCad 4.0.5.

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The bus name needs to match the prefix of the individual labels.
You need to add the range [x…y] to the bus name

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8 Likes
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I’m having a similar issue: how do you get the connection to be visible across sheets? ex. what is the OUT[0..1] symbol/element type?

Also: if I want a named bus, ex. SHEET2{SPI}, how should I name the connections? ex. to connect MYSECONDSCHEMATIC’s SPI “bus” to main sheet’s SPI pins at a specific symbol.

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