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Electronics => PCB/EDA/CAD => KiCad => Topic started by: kripton2035 on December 22, 2015, 07:30:15 pm

Title: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: kripton2035 on December 22, 2015, 07:30:15 pm
Hi,

I just tried today the new kicad 4.01 on a mac
I have a simple pcb to make, an adapter tssop to dip
so I want to make a pcb only, no schematic or ratnest needed
is it even possible
I placed the two packages, then when you draw a trace, it draws and then it disappears ?

is it even possible to work like that ?
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: c4757p on December 22, 2015, 07:35:50 pm
You can do that, but you completely lose DRC, so it's up to you to verify that your board is correct and manufacturable.

Enter routing mode (press X), then call up the routing options (press E). Select "Highlight collisions" and "Allow DRC violations", and you'll be able to route from anywhere to anywhere.

However, if anyone asks... uh, someone else told you how to do that.

I don't recommend it.
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: kripton2035 on December 22, 2015, 07:50:10 pm
thanks, but I can enter route mode with X, then "E" does nothing , and I can't find any routing options menu somewhere ???
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: c4757p on December 22, 2015, 07:52:06 pm
You must have got yourself into the old "legacy" router, then.

Either: Press F11 to switch to the new OpenGL one.
Or: Click the "bug" icon on the left toolbar, to get the legacy equivalent of what I just told you.
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: kripton2035 on December 22, 2015, 09:21:03 pm
sorry to take your time, but nothing of these works ! f11 does nothing more, and clicking the bug icon nothing more...
may be the mac version of kicad is not as complete as the others ?
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: c4757p on December 23, 2015, 04:24:08 am
No, the OS X builds don't lack any features - certainly not non-system-dependent ones like that. It's possible that the hotkeys are different and I'm just not aware of it, though. Try "View -> Switch canvas to OpenGL".
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: kripton2035 on December 23, 2015, 07:23:56 am
ah it's ok - the shortcut was alt-F11 in fact. now it's better and the router options are available
thanks again.
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: Cloud on January 16, 2016, 02:55:55 pm
Or in settings you unclick "enforce design rules"
Title: Re: can you make a pcb in kicad without a schematic and so no ratnest ?
Post by: Godzil on January 26, 2016, 03:28:54 am
There is a way to not disable the DRC, but it is really tedious.
You can give/change the net name for each pad, so you just need to:
1 - place all the footprints you want,
2 - put you cursor on a pad, press the "e" key on your keyboard to open the edit windows  (you may have to clic on the pad before, or it may show a popup menu to select, select the pad and not the footprint.
3 - in the "Pad Properties" windows, there is a field "Net name", give the pad a netname that need to match all the pads you want to connect
4 - clic OK to validate
5 - Go back to 2 for each unchanged pad.

Then the board connectivity should be good for using the DRC to check if it's correctly routed, if it's still not see the connection, you may use the "rebuild connectivity" in the netlist window, or just close PCBnew and start it again.

It's far from perfect, but will works.


I've done that on a design recently to swap some pin without going to modify first the Schematics (I'done that after, not perfect, but at that time I didn't wanted to before changing the Schematics)