Designators with no number

When annotating the schematic in Eeschema all designators are given a number.
If you have a part which you want to designate something like ‘PortC’ then KiCad renames it to ‘PortC1’. If you rename it back to ‘PortC’ then the ‘Electrical Rules Checker’ in Eeschema fails with error:

Item not annotated: PortC?

Annotation required!

Is there any way to get around this?

I take it that the ‘Reference’ fields in your world are the ‘designators’?

Afaik (I’m just an amateur) those references are following a standard that more or less is the same the world over.

What you want to do is not formally taken care of in code afaik.
To transfer the kind of information between schematic and layout you are establishing I use labels (track, global and hierarchical sheet labels, plus text fields) and in the layout either text in copper or silkscreen.
In the schematic the text fields + labels help to explain what it is and on the layout (if needed) the text placed manually guides the user what is what.


Let’s ask the other way around - what do you want to do?

Hi Joan,
Thanks for the response!
Yeah, your approach seems reasonable. I’d like the silkscreen reference to be readable and not contain extra info. See in the image below, USB1 to describe the part should really just be USB.

I think for now I’ll just set the ‘USB1’ reference field as invisible and add Text on the footprint layer with the name I’d like. (image below)

It’s a little messy because obviously, if I move the part, the text field won’t be dragged around with it. I guess if I leave this to be one of the final steps in the layout process it reduces the chance that I’ll need to move a part.
Alternatively, I could rename the reference field in Pcbnew but that seems a little dodgy to me. I assume that if I modified the netlist in Eeschema, say I added a trace to a pin, then it would no longer import correctly when I loaded the netlist in Pcbnew.

[quote=“WildSpy, post:3, topic:4366”]
…if I move the part, the text field won’t be dragged around with it. I guess if I leave this to be one of the final steps in the layout process it reduces the chance that I’ll need to move a part.[/quote]

Correct. I do the same. It’s one of the final steps before I check out the gerbers (final pass to make sure the user-interface is applied correctly).
And what if you want extra information on your board that doesn’t have a part associated with it?
Or the other way around, what if a part which usually bears an information field shouldn’t have one?

You naturally could put that information into the footprint, but then you have to edit the footprint if you want to change the information + it’s relative position/orientation to the footprint in your layout. And if it appears more than once you’d change both at the same time.

The manual silkscreen text fields are the current state of the art.
If you want to go without silkscreen (to save money/time/etc) you can also use the copper or soldermask layer in areas where there is some space.
Works pretty well too.

As I said, the data in the reference field is being used by KiCAD for internal and external tracking. You can’t really use it for your purposes.

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Simply use the “value” field instead of the “reference” field. Change the footprint to have the reference hidden and the value showing.

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Hi Joan, I realize this thread is fairly old, but I have several observations that have bearing on this thread:

Reference designators have several key uses: They are used by manufacturing to identify where BOM parts belong, but they are also used by repair and rework to correlate parts between the schematic and the PCB. For the sake of prototype manufacturing, rework and repair, using a more intelligent naming scheme for reference designators increases productivity and reduces errors. They can also be used when laying out a PCB to understand correlations between groupings of parts without necessarily having to refer back to the schematic, and can be a very useful hint to PCB layout engineers on highly complex designs. I have used more complex naming schemes in the past with Orcad, gEda and Altium, all of which can be made to play nicely with custom reference designations. Kicad is the sole standout in forcing its reference naming scheme on the users.

Another relevant point is that I have made many complex designs in which multiple different end products are combined onto a single PCB with different component populations for different configurations. I have advanced this approach to the point where for the sake of total PCB density, I combine disparate types of parts onto compatible pads (for example, designs that have a single 0402 footprint that could be a capacitor, resistor or diode depending on the particular configuration). Under these circumstances the standard Reference designator naming conventions completely fall apart.

The “best” solution mentioned in this thread was to hide the reference designators and display a “value” field instead, but this causes all kinds of problems for rework and repair when they need to find out what a component is supposed to be, but the text on the silk screen doesn’t align with anything in the BOM.

TL;DR Reference Designators are not the one-size-fits-all thing that everyone assumes they are, and every tool except Kicad recognizes and at least allows for it. Its too bad really because in all other respects, Kicad 6.0 is as good or better than the proprietary tools.