From:	MERC::"uunet!CRVAX.SRI.COM!RELAY-INFO-VAX"  6-JUL-1992 14:34:17.66
To:	mcsun!dxcern!dscomsa.desy.de!vxdesy.desy.de!sys_sprute
CC:	sprute@vxdesy.desy.de, info-vax@sri.com
Subj:	RE: serial <-> virtual port ??

	Lars Sprute <sprute@vxdesy.desy.de> writes:
>
>I installed a modem on a serial TXA port of one of our VAX 6000 last days.
>There was lots of trouble with the 'set term' command, which is not very well
>explained in the manuals.
>
>Anyway, after several tries I succeeded, but I was a little astonished about
>the device and terminal characteristics I saw. The serial device acts
>like a virtual device ?!?
>
>The device and terminal characteristics are included here:
>
>Terminal TXA2:, device type VT200 Series, is online, device set /NOAVAILABLE,
>    record-oriented device, carriage control, device is a physical terminal
>    accessed through a virtual terminal, error logging is enabled.
>
>    Error count                   16    Operations completed               7664
>    Owner process                 ""    Owner UIC                      [SYSTEM]
>    Owner process ID        00000000    Dev Prot        S:RWLP,O:RWLP,G:RWLP,W:
>    Reference count                0    Default buffer size                  80
>
>
>Terminal: _VTA10:     Device_Type: VT200_Series  Owner: SYS_SPRUTE
>Physical terminal: _TXA2:
>   Input:   9600      LFfill:  0      Width:  80      Parity: None
>   Output:  9600      CRfill:  0      Page:   24
>Terminal Characteristics:
>   Interactive        Echo               Type_ahead         No Escape
>   Hostsync           TTsync             Lowercase          Tab
>   Wrap               Scope              No Remote          Eightbit
>   Broadcast          No Readsync        No Form            Fulldup
>   No Modem           No Local_echo      No Autobaud        No Hangup
>   No Brdcstmbx       DMA                No Altypeahd       Set_speed
>   Line Editing       Insert editing     No Fallback        No Dialup
>   Secure server      Disconnect         No Pasthru         No Syspassword
>   No SIXEL Graphics  No Soft Characters No Printer Port    Numeric Keypad
>   ANSI_CRT           No Regis           No Block_mode      Advanced_video
>   Edit_mode          DEC_CRT            DEC_CRT2           No DEC_CRT3
>   No DEC_CRT4
>
>Does anyone have an explanation ?
>Does it matter, that I've fooled around with the 'set term/dialup' command ??
>


	The explanation will be found on page 6-19 of "Guide to Setting Up 
a VMS System" order number AA-LA25A-TE.

	Briefly, someone has enabled virtual terminals on your system by
issuing (probably in one of the startup files) the SYSGEN command CONNECT 
VTA0 /NOADAPTER/DRIVER=TTDRIVER.  Now, any terminal with the 
TT2$M_DISCONNECT characteristic set prior to login is treated as a virtual
terminal.

	You can suppress this behavior by including the following command 
in your startup.

$ SET TERMINAL -
	/PERMANENT -	! Make settings permanent
	/NODISCONNECT -	! Disable virtual terminal
	/DIALUP -	! Give user the DIALUP identifier
	/MODEM -	! Use MODEM control
	/HANGUP -	! Hang up the phone when user logs off
	/AUTOBAUD -	! Detect the user's baud rate and set it.
	/ALTYPEAHD -	! Use the alternate typeahead buffer.  The
			! alternate typeahead buffer can be made larger
			! than the regular one.  This is helpful if you
			! are doing file transfers.  See SYSGEN parameter
			! TTY_ALTYPAHD.
	/HOSTSYNC -	! VAX will send XOFF when its buffer is nearly
			! full and XON when it is ready for more input.
			! See SYSGEN parameter TTY_ALTALARM.
		_TXA2:

	Some of these qualifiers are optional.  With some types of MODEM, 
you would not use /AUTOBAUD.  /ALTYPEAHD is not necessary unless you are 
using the port for something other than a human typing at a keyboard.


*************************************************************************
*                                                                       *
*                        Here, there be dragons!                        *
*                      dragon@nscvax.princeton.edu                      *
*                                                                       *
*                                                Richard B. Gilbert     *
*************************************************************************