Unexpected 2 pins connected on a part

Hi all,
I can’t find out why the pin-21 (GPIO21) is unexpectedly connected through the pin-02 (GND) on my newly created part. Symptom is:

  • when I click to pin-21 on the breadboard, we can see yellow highlighted connection through pin-02. Or if clicking to pin-02, we will also see pin-21 is yellow highlighted. (see screenshots)
  • In Schematic view, if we move the switch/button to the other side of the MCU i.e. near pin-21 then it automatically connect to pin-21 rather than pin-02 (GND) as design.

References are in attachments. Helps are really appreciated.

I am using Fritzing v1.0.2.

Thank you very much,
button03-esp-nostd.fzz (47.7 KB)
Mtiny ESP32-WROOM-32E DevKit.fzpz (38.4 KB)

That would be because your bus definition in the .fzp file is incorrect.

clicking on GPIO22 lights GND (which it shouldn’t) but does not light the other GNDs (which is should. That is because of this in the



  <bus id="GND">
   <nodeMember connectorId="connector1"/>
   <nodeMember connectorId="connector28"/>

which should be


to tie the ground pins together, but not connector28 (which is not ground.)


Thank you very much for quick support. It works.

Now, can we edit and correct that .fzp/.fzpz file in Fritzing? And then update it into existing sketch? Is there any menu function in Fritzing rather than tweaking it manually? (i.e manually unzip the .fzpz, edit the *.fzp, zip all *.svg & *,fzp into a new *.fzpz then replace it in Fritzing folder manually.)

Best regards,

Parts editor will do this. The bus definitions are “internal connections” and somewhat complex to change (which is why I usually ignore parts editor in favor of editing the files directly.) These two tutorials should help, Old_Grey’ deals with parts editor mine with editing the files. In either case you are best to run the part through FritzingCheckPart.py (detailed in my tutorial) to both check it is correct and correct things that the svg editors do that Frtizing objects to (such as putting px in font-sizes.)

I lately learned there aren’t links to the videos in Old_Grey’s tutorial so you need to do a google search for the title and then they come up on YouTube.


1 Like

Thank you very much. I already manually edited the bus identifications in text editor yesterday. Will look at the Old_Grey’s guide to see how is doing it in Fritzing GUI.

Best regards,