HP OpenVMS Systems

Configuring dedicated serial terminal line?

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The Question is:

 
We want to use terminal port (TTA0: or TTB0:) to exchange data using our
 private protocol. Of course we use QIO system services. The problem is when we
 restart system (we install our software on AlphaStation 500). If second side
 sends data to Alpha during
 booting procedure, VMS grabs terminal port and runs LOGIN.EXE. So the second
 side could see "Welcome to OpenVMS..."
 
How can we permanently grab terminal?
 
 

The Answer is :

 
  In SYSTARTUP_VMS.COM, issue the DCL command:
 
    SET TERMINAL/NOTYPEAHEAD/PERMANENT ddcu:
 
  This will prevent any unsolicited terminal input on ddcu:, and
  this unsolicited input is what triggers JOB_CONTROL to start up
  LOGINOUT on the terminal.  Once LOGINOUT starts up on the serial
  line, you can see interesting behaviour (eg: audits, process
  creations, etc) as LOGINOUT tries to "chat" with whatever device
  is hooked onto the remote end of the serial line.

  

     

     
answer written or last revised on ( 5-MAY-2000 )
     
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