I try to place a power port with a value VBAT not VDD. I find I can’t edit the value of any power port in the list. How to change the value to anything I want?
You need to copy/modify the symbol in the symbol editor and save it to your personal symbol library… what you got there is the option editor in eeschema, right?
The pin is set to invisible.
This tells eeschema, that this will become a net for global/power purposes. See the green circle in the symbol editor window for that pin.
You need to change the VDD value to VBAT and save a new symbol for this.
Afaik you can’t edit the symbols/pins in the schematic editor on-the-fly and adapt a VDD symbol to become a VBAT symbol.
It means I have to create a new power port or create one based on the current VDD? Then, I can use this power port with any value I want because its value is changeable, right?
Best/fastest/less error prone would be, to work from the existing symbol, and saving it in a new local library.
Yes to 2nd part of Q. [edit] see below…
Wait, I thought one still needs to create a separate power symbol for each global signal (e.g. GND, +3.3V, +VBAT etc), has that changed?
Oh, sorry… misunderstood that 2nd part then. Answer is no, this custom symbol behaves exactly like the VCC or GND symbols from the common kicad library. You need to make a separate symbol for each of the values you want… 3.3V, VBAT, 5.5V, 2.8V, etc. pp.
Sorry for the confusion.
OK，thank you for help. I think it’s inflexible. If it can be made better like AD, power port is a special net name, it will be helpful for the designers.
I’ve never had the need to make custom power symbols. I just do the following:
- Create a global net with the name of the power supply such as “+5V”.
- Connect a PWR_FLAG symbol to the net so KiCad knows it’s a power supply.
- Connect the net to the pins of the chips using global labels with the name of the power supply net.
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First, thanks for help. But sorry, I am a new user of KiCAD. What do you mean by “Step 2: Connect a PWR_FLAG symbol to the net”? Or I mean what is “PWR_FLAG symbol”? Where can I find it? Is it just the power port?
It’s a symbol in the POWER library with the name “PWR_FLAG”. Just drop it into your schematic and attach it to a net that you want to be your power supply.
Yes, I’ve found it. Thanks a lot. 
I split a discussion as the new addition did not really fit here.
But for reference we now have a FAQ article that explains how to make a power symbol as one of its sections: Tutorial: How to make a symbol