> I have an LM7805C here powering a PIC16F628, which is simply
> driving 7 LEDs
> with a common cathode. I have this all on a breadboard, with the
> ground from
> a 9v battery in the slot directly in front of the 7805 ground pin. Next to
> that is the wire from the PIC ground, and next to that is the
> wire from the
> LED ground, so they all go into the 9V battery's ground.

By "breadboard", do you mean one of those solderless breadboards
such as AP, Global Specialties, etc.?  If so, remember that the
horizontal buses (busses?) are usually split halfway across...
they don't run continuously from end to end.  This can cause
bizarre things to happen if you forget to add jumpers in the
right spots.  Also, I've found that those things can be less
than reliable and it pays to verify connections with a meter.

Brian Aase

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