Connecting to a Pi Pico

Hi, I am new to this software and I have no doubt I have much to learn…and fix but I am struggling with the connections to a Pi Pico.
I keep getting these errors and I cant see why. The supply pin and some switches need to be connected to the 3.3v line but the software keeps generating an error.

ErrType(4): Conflict problem between pins. Severity: warning
@(26.67 mm, 156.21 mm): Pin 3 (Passive) of component SW4 is connected to
@(165.10 mm, 81.28 mm): pin 36 (Unspecified) of component U1 (net 40).
ErrType(4): Conflict problem between pins. Severity: warning
@(165.10 mm, 81.28 mm): Pin 36 (Unspecified) of component U1 is connected to
@(26.67 mm, 124.46 mm): pin 3 (Passive) of component SW2 (net 40).
ErrType(4): Conflict problem between pins. Severity: warning
@(165.10 mm, 76.20 mm): Pin 38 (Bidirectional) of component U1 is connected to
@(167.64 mm, 190.50 mm): pin 1 (Power output) of component #FLG0102 (net 41).

Did you make that schematic symbol for the Pico yourself?

KiCad’s ERC is complaining about “Unspecified pins”. and when you look at: Schematic Editor / File / Schematic Setup / Electrical Rules / Pin conflicts Map, then you see that a pin with type “Unspecified” generates a warning for almost any connection. You (or the person who made that symbol) should choose some other pin type.

Thanks for the reply. The Pico symbol was downloaded from Github, It appears to be the only version I could find.
I am still very new to this and thought I was doing well for a first outing. Would it be easy for me to change this myself or should I really be looking for a better symbol?

The simplest (and also ugliest) way to “fix” it is to either simply ignore ERC, flag them as ERC exceptions or change the pin conflicts map.

A much better method (and also easy) is to fix the schematic symbol itself. Just load it in the schematic symbol editor and then hover the mouse cursor above a pin, press e to edit it’s properties and then change it’s electrical type. You can also do this quicker with: Symbol Editor / Edit / Pin Table.

Loading the symbol in the Symbol Editor can also be done via different paths. The quickest is to just hover over the symbol in the schematic and then press [Ctrl + e] (When you close the Symbol Editor, KiCad asks you if you want to update the symbol in the schematic itself. A neater way is to modify the symbol in the library directly.

Also, if you’ve done this and got a satisfactory result, then it would be nice to create a merge request for that github repository. Those uC pins should never have been set to “Unspecified”, which is an indication that the person who made it also did not have much experience with KiCad (or schematic design), and he can learn something from it too.

Also:
I’ve looked a bit at different uC families of the KiCad default libraries, and those general purpose I/O pins are usually set to the “Bidirectional” pintype.

I tried it and that appeared to fix the errors I was having, thanks.

I just appear to need to fix the pico footprint or create one for it. At the moment, it does not appear to have one associated with it. Another learning topic I think.

I created Footprint and Step (3D-Model) for some Pico projects (perhaps it will satisfy your needs).

Basically same part with two different footprints. Note: Castellated mounting is to solder on Top of PCB to SMD Pads (you can Edit/Change as desired).

You can create your own Symbol for the Schematic… very simple, then associate it with the Desired footprint

Pi_PICO_wHeaders.STEP (3.7 MB)
Pico-R3-PICOPICO_assm_140121.step (947.8 KB)

Pi_PICO_Castellated.kicad_mod (9.1 KB)
Pi_PICO_wHeaders.kicad_mod (895 Bytes)

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