Component With A+B Parts Swap Sometimes

Schematic
1

I’m new to KiCad and have been using Eeschema to create a schematic. Every once in a while I pop back into my MCU sheet to check up on something, and find that the MCU component’s IO portion (unit A) has swapped spots with the power portion (unit B). Thankfully the wires all stay in the same places so it’s a simple matter of moving unit A back to A’s spot and unit B back to B’s spot and re-generating the netlist. But the problem appears to happen randomly, and I can’t tell it’s happened without going and looking in that sheet.

If you look at this screenshot, you can clearly see that the large IO section A is nicely centred in unit B’s spot, and vice versa. What’s going on – is this a bug that somebody else has encountered as well, or is it something I’m doing wrong? This has happened a couple times already and the parts always centre themselves in the opposite spots, so it’s not me randomly dragging my cursor around or something bizarre like that … :slight_smile:

634×579 9.64 KB

2

You have “Units are interchangeable” option checked for your MCU symbol. Back to library editor, load your symbol and open its properties. Just uncheck this option and save library again. Now the annotation tool will stop swapping your units.

2 Likes
3

Turns out the logic is opposite to what you said (check the box to indicate units are not interchangeable), but since I’m a human and not a computer I figured it out. :wink:

Thanks mate, that should cure the mysterious component swapping.

After coming from DesignSpark, I am starting to really like KiCad. Many thanks to the devs who have spent tens of thousands of hours on making this program great!