Pin connected to other pins, but not driven by any pin (Data pins)

Hi there, ERC gives this problem. What confuses me is that should data pins also have to be driven by any other pin, as there is a clear connection between the MCU and the momory as shown on the pics.


But when i open the memory symbol in the symbol editor all the pins are Input pins, shouldn’t they be bidirectional or not?

I am not sure bidirectional is the correct type here. I have not looked at the datasheet but pins starting with “A” on a memory chip are normally the address input pins. If they are however the data in/out pins then they could potentially be some type of pin that can be both input or output. These could then for example be bidirectional or threestate.
You might want to check Electrical type of schematic symbol pins (KiCad 4 and KiCad 5)

Hi, i checked the datasheets of both and turns out the I/O pins on the memory should be bidirectional and the address pins of input electrical type.

As for the MCU all the pins should be bidirectional (the ones which gave errors). Now the error disappeared.

But i’m having another severity problem here:


An LDO, where the voltage output is connected as seen in the picture.

SPI Oscillator
And on the other side the series programmable oscillator.

If OE is “Output Enable” it should be defined as input and not output, are you sure the LTC6903 is from the official library ? I do not have it on mine and as you see I have all the 15K+ symbols.

Which version of KiCAD are you using (please copy the version information from ‘Help->About KiCAD->Copy Version Info’ here)

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It’s from a library i imported from a project i found on internet. Changing it to type input solves the problem, thanks a lot.

Btw, my Kicad version is 5.1.6

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