Jumper settings for 120 Ohm connection

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Dieter Spaar spaar at mirider.augusta.de
Sat Feb 28 13:27:40 UTC 2009


Hello Holger,

On Sat, 28 Feb 2009 12:55:04 +0100, "Holger Adams" <holger at kernreaktor.org> wrote:
> 
> OK, I think I know where the problem is - there must be a cableing
> problem with the Twinax connectors.
> 
> So there is my next question:
> Which pin of Y01 is TX+ and TX-?
> Which pin of Y02 is RX+ and RX-?

The polarity does not care, you can exchange TX+ with TX- and RX+
with RX-. A simple test for just the correct wire without connection
the BS-11:

 - On the cable which goes to Y01 you should be able to see a
   signal with an oscilloscop between TX+ and TX-.

 - If you connect the two TX lines with the two RX lines (loopback,
   polarity does not care), the card should synchronise and the LEDs
   should not longer blink. Attention: I have tested this on Windows
   only, with a loopback, I can see that the card synchronises, however
   I don't know what mISDN does, but I guess it will also synchronise.

If this works, you know that the cable is OK.

Best regards,
  Dieter
-- 
Dieter Spaar, Germany                           spaar at mirider.augusta.de




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