[simpits-tech] Whats happenin?

[Contrapezist]

I was going to suggest some strangeness with the clamp diodes, my dealings with the ULNXX IC's they can do some strange things with out pull up/down and unloaded. 

It is a sad day for me. I made what was possibly the last trip to my favorite junkyard (actually the only dig away and load up junkyard round these parts). They started clearing it out several months ago after the old man died, I went to pillage my favorite junk pile today and it was gone. Did latch on to some things Ive been pondering not quite sure if its what I want/need and some other random bits because they may be gone shortly. Seems like all the old junk men are slowly dying off and the junkyards along with them.
Austin
  ----- Original Message ----- 
  From: Per Eriksson 
  To: Simulator Cockpit Builder's List 
  Sent: Wednesday, August 25, 2010 2:28 PM
  Subject: Re: [simpits-tech] Whats happenin?



    Right now I'm chasing a damn weird oddity with my Gazoutta16 board.
    Turning channel 8 on activates channels 1-7 as well.  The weird thing is,
    my logic probe tells me that only the 8th input on the ULN2803 has gone
    high.  The only thing I have left to test is the ribbon cable.  This is
    weird because it happens to both the prototype and one of the production
    boards.  I've checked it with a multi-meter and there's no errors on the
    board.  It's enough to drive me even crazier. :)


  Butting in: Did you accidentally connect the flyback diodes pin to the 8th output? That would behave that way, sort of. Of course, you'd have had to leave that pin unconnected in the design, or at least not connected to the power supply positive.


  Just a quick thought...
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