Re: Parallel port hardware


Placed a printerport schematic on ABSE.

Also see you point for communicating with PGDx. You will need to keep the
printer control line high as long as the PGDx can go into outputmode. If
not you can get a collission and too high a current in the circuit. That
old 7406 could sink a lot of current but one cannot know about the modern
integrated printerports. Guess you do not know about the PGDx either.
(Guess it's not open collector as you would not have a problem if it was.)
So you will need that serial resistor for current limiting. Ever saw some
type of electronic collission detection but it is too late to look after
it now.

petrus bitbyter




You will need to limit the current somehow because sometimes both outputs
will happen happen to be active at the same time


Yes, this is the main problem. Sure I can program it so its high through the
programming but I'd rather not take that chance in general. I'm not quite
sure how to handle this. The problem is with the pic though. I could add a
resistor to limit the current but then it will reduce the voltage. Although
it might not matter to much.

I send an schematic to alt.binaries that shows the idea I'm looking at.

Thanks,
Jon.


.

Relevant Pages

  • Re: Parallel port hardware
    ... Also see you point for communicating with PGDx. ... keep the printer control line high as long as the PGDx can go into ... Did not find the collission detection but I think the circuit below ...
    (sci.electronics.design)
  • Re: Parallel port hardware
    ... petrus bitbyter pieterkraltlaatditweg@xxxxxxxxxxxxxxxxx posted to ... Also see you point for communicating with PGDx. ... keep the printer control line high as long as the PGDx can go into ... serial resistor for current limiting. ...
    (sci.electronics.design)
  • Re: Parallel port hardware
    ... Also see you point for communicating with PGDx. ... keep the printer control line high as long as the PGDx can go into ... serial resistor for current limiting. ...
    (sci.electronics.design)
  • Re: Parallel port hardware
    ... Also see you point for communicating with PGDx. ... printer control line high as long as the PGDx can go into outputmode. ... So you will need that serial resistor for current limiting. ... Did not find the collission detection but I think the circuit below will ...
    (sci.electronics.design)