Re: 5V+ Supply for Gecko? Still confused!

Hmm.. myabe I'm having a brainworm day, but I just don't get this
still.

Okay, since we've established that the gecko has it's own internal
bus which is powered from the 18-80V motor supply, and we know this
powers the encoders....

The Step/Dir pins and the 5V+ pin of the gecko make up two opto-
coupled LED's emitters. From looking at the circuit diagram, it looks
like the step-dir pins are triggered by negative voltage on the
parallel port. Am I correct in assuming that when the parallel port
pulses, it is negative?

Now surely, if this is going to be negative, then there wil be a
positive pin, or two in the parallel port, as I don't see
lineprinters needing the PC power supply connected. All we need to do
is light up two opto-isolator LED's from the parallel port - surely
there is going to be enough power/connections for that?

Sorry if this is painful.... there just seems to be something I'm not
getting here.