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Wiring serial devices? (pinouts)

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The Question is:

We are trying to communicate with a periferal device through a terminal server
 on our VAX.  We have another system running successfully with the same type of
 periferal device.  I copied the LAT setup and the SET TERM setup from the
 working system, so I be
lieve those are set up properly.
The problem is that any time we try I/O through this LAT port, we get the error
 "Data set hangup".
The serial connection is currently wired for pins 2 & 3 plus grounds only.
 We've also tried all kinds of ways to connect pins 4-8 & 20 for hardware
 handshaking but that doesn't help.

The Answer is :

  Please start with (1607).
  The HANGUP would initially appear to indicate this device is miswired.
  This may or may not be related to the setting of modem control on the
  host or on the terminal server.
  You WILL require access to a testing device known as a breakout box, a
  serial line signalling diagnostic tool.  Without access to this ESSENTIAL
  piece of serial line test equipment, you will be left to guess what is
  occuring and guess what signals are required by the particular serial
  peripheral device.
  As for one common EIA-232 serial wiring scheme:
    2-2 or 2-3 and 3-3 or 3-2, depending on device
    4-5 locally on each connector (disables hardware flow control)
    6-8-20 to 6-8-20 on the other (limited modem control)
  Information on various pinouts is included in the OpenVMS FAQ.
  Also please acquire and apply all mandatory ECO kits and any ECO kits
  related to LAT or to network operations.

answer written or last revised on ( 25-JAN-2001 )

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