Hi Justin,
each symbol's pin should have the pintype attribute set. This shows the
type of that pin (an output, an input, open collector,...).
If it's not set, then the DRC checker assume it's an unknown pin. The
DRC matrix is configured so an unknown pin connected to whatever type of
pin generates an error, which is what you are getting ("unknown
connected to..." .
The DRC checker is also telling you the net is not driven. This means
that
only input or unknown pins are connected to that net, and that net will
be theoretically floating.
If you want to fix this, you have to edit the symbols you are using and
set the pintype correctly. For R's, C's, and L's it should be
"pas" (passive), for example. I'm not so sure about the voltage
generator.... maybe one pin should be "out" (output) and the other
"pwr" (power)?
There are some symbols with missing pintype attributes. They have to be
fixed.
Regards,
Carlos