When I run DRC, I get warning messages similar to those shown below on bus signals in my design. What can cause these warnings?

Checking for Unconnected Nets
WARNING DRC0007: Net has no driving source test[0..1]:
WARNING DRC0006: Net has fewer than two connections TEST0:
i have attached the image file of schamatic.
please help.....

 

Looks like a Kicad schematic. Nothing on attachment was marked, and couldn't find anything that said test[...] or TEST0, but generally...

"Net has no driving source" can typically be ignored. You see it in places like common ground connections where everything is looking to get a ground, but nothing is supplying ground. Yeah, that's meaningless but the rules checker is looking for a driver.

"Net has fewer than two connections" means something is isolated by itself. A pin that goes nowhere and the like. Can (and should) be suppressed with the NO CONNECT tool.

 

thanx for the reply.....
can you please show me the mistake in my circuit and what changes i should do.. to correct the problrm....

 

To avoid the "Net has no driving source" I will typically make every pin on every device a a "passive" pin for "Electrical type" in the pin properties menu in the Component Library editor, then save the changed part to either the standard library or a custom lib I create just for that project. The DRC (design rule check) allows these pins to be connected in any way whatsoever.

Custom libs help when you start something new so you don't step on previous work.

You could also define one pin in the chain as a "Power output" type, then the one pin drives all the others.


For "Net has fewer than two connections" you can click the error in the DRC window and it will drop you back to that unconnected wire. HOW you fix that depends on what the wire should be doing. If it is truly not connected anywhere then just give the pin a NC tag (blue X in right side tools). If it should go somewhere then something went wrong in the wire routing: when I get that (and I don't see why) I'll delete the wires and redraw them.