I’m trying to update my reference designators from my schematic to my PCB. However, when I do so it is causing me to have to re-place each component that had a changed ref des. How do I update the reference designators without having to move my components?
I have already tried loading the new netlist and pressing the “update PCB from schematic” button. Within those buttons, I have tried both options listed under “Match Method.”
The normal link between schematic symbols in Eeschema and existing Footprints in Pcbnew for a project is done with “timestamps” a.k.a. “UUID”.
Therefore the “Match Method” should be “Keep existing symbol to footprint associations”
With “Options” also check “Update footprints”.
[Edit: Oops]
The “Update footprints” is not relevant here. With a test it also updates the Refdes of a footprint if this checkbox is unchecked.
In the text box with “Changes to be Applied” there is a listing of text of what Eeschema will do when you execute the command.
In the screenshot below, I changed the RefDes: “Q345” to “Q42”, and KiCad tells me it’s doing something good with green text.
If you still can’t get it to work, then make a new small project (or a copy of your existing project) and experiment a bit with just a handful of components.
If you then still can’t figure it out, post some screenshots, and/or the full text here.
Below a part of the copied text (normal [Ctrl +C] and [Ctrl = V] in this forum):
Info: Processing component “R36:/5F575744:Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal”.
Change Q345 reference to Q42.
Add net Net-(Q42-Pad1).
Reconnect Q345 pin 1 from Net-(Q345-Pad1) to Net-(Q42-Pad1).
Add net Net-(Q42-Pad3).
Reconnect Q345 pin 3 from Net-(Q345-Pad3) to Net-(Q42-Pad3).
Add net Net-(Q42-Pad2).
Reconnect Q345 pin 2 from Net-(Q345-Pad2) to Net-(Q42-Pad2).
One more tip: don’t mix update types in one go. When the schematic and the pcb are in sync at first, either change the references in the board and update using “Re-associate”, or change them in the the schematic and update using “Keep existing”. Don’t change in the schematic and in the pcb in one go.
I have been thru the same issue as you mention in the original post. It is easy to get it wrong but also easy to get it right. No need to go outside the options built into KiCad.