Properties for custom parts


I’m trying to develop custom parts for my model railroad hobby,
but I’m stumbling over parts properties:

How are properties made
a) changable - mine get fixed after saving-
b) provide lists for selection - for example “common” “anode”/“cathode” - for multiple LED’s etc. , for simply “yes”/“no”

In breadboard view, is there a possibility for combining wires to busses ? For example I2C SDA/SCL/GND or servo signal/+5V/GND. This would save space and make the view not so crowded.

There is no ‘bus’ equivalent in the breadboard view.

(with exceptions) Inspector does not change properties within a single part. Instead, when two (or more) parts have the same family value, other property names that exist in the parts become selectable (drop down lists). Choosing a value from the lists swaps the current part for the one with the selected value. So with parts that have (in the fzp file)

First part

<property name="family">my set of parts</property>
<property name="type">THT</property>

Second part

<property name="family">my set of parts</property>
<property name="type">SMD</property>

Inspector will show a “type” dropdown that will allow switching between SMD and THT. The parts can use some or all of the same view image files when appropriate. If there are multiple properties that you want to select on, the number of needed parts can get large fast. If you have a part that can be 5V, 9V, or 12V, each with current ratings of 1A, 2A, 5A, that will need 9 parts to implement.

  • 5V at 1A
  • 5V at 2A
  • 5V at 5A
  • 9V at 1A
  • 9V at 2A
  • 9V at 5A
  • 12V at 1A
  • 12V at 2A
  • 12V at 5A

Using the same family value, and different values of “voltage” and “current” combinations in each part.

The “part number” property is special. It can be modified directly, without needing a separate part for each variation.

In core parts, some properties have selectable lists, or editable values without multiple parts existing. That allows changing resistance, capacitance, voltage, and certain other properties. Those are ‘factory’ parts. The parts are actually created as needed, without storing all of the possible variations. Custom parts do not support that.

Some recent changes to the application are supposed to allow combining multiple parts into a single fzpz, but I have not tried it. If that works the way I expect, the fzpz file (a zip file) could contain the 9 fzp files for the above example, plus the needed view svg files. Which might be just 3 extra files. Or 2, if the part does not need a PCB view.

In Fritzing bus has a different meaning than in other EDAs (where multiple wires exist in a single container), in Fritzing a bus describes pins that have an internal connection to each other in a single part. There isn’t a bus part that contains many wires (at least so far.)
One quirk (actually a bug) on part properties that may bite you, if you load 2 custom parts in to Fritzing which should have selectors, the selectors may not become active until you save the mine parts bin and restart Fritzing. If you are making custom parts these two tutorials apply to current versions of Fritzing (most of the rest are for older versions)

and this Inkscape extension makes creating schematics much easier.

If you run in to problems (which you probably will :slight_smile: ) feel free to post the .fzpz file that is failing and one of us will give you a hand.