4.3BSD - /usr/man/cat4/dn.0

DN(4)                                                                    DN(4)


NAME
       dn - DN-11 autocall unit interface

SYNOPSIS
       device dn0 at uba? csr 0160020 vector dnintr

DESCRIPTION
       The  dn device provides an interface through a DEC DN-11 (or equivalent
       such as the Able Quadracall) to an auto-call unit (ACU).  To  place  an
       outgoing  call one forks a sub-process which opens the appropriate call
       unit file, /dev/cua?  and writes the phone number on  it.   The  parent
       process  then  opens  the corresponding modem line /dev/cul?.  When the
       connection has been established, the open on the modem line,  /dev/cul?
       will  return  and  the  process will be connected.  A timer is normally
       used to timeout the opening of the modem line.

       The codes for the phone numbers are:

       0-9    dial 0-9
       *      dial * (‘:’ is a synonym)
       #      dial # (‘;’ is a synonym)
       -      delay 20 milliseconds
       <      end-of-number (‘e’ is a synonym)
       =      delay for a second dial tone (‘w’ is a synonym)
       f      force a hangup of any existing connection

       The entire telephone number must be presented in a single write  system
       call.

       By  convention,  even numbered call units are for 300 baud modem lines,
       while odd numbered  units  are  for  1200  baud  lines.   For  example,
       /dev/cua0  is  associated  with a 300 baud modem line, /dev/cul0, while
       /dev/cua1 is associated with a 1200 baud modem  line,  /dev/cul1.   For
       devices such as the Quadracall which simulate multiple DN-11 units, the
       minor device indicates which outgoing modem to use.

FILES
       /dev/cua? call units
       /dev/cul? associated modem lines

SEE ALSO
       tip(1C)

DIAGNOSTICS
       Two error numbers are of interest at open time.

       [EBUSY]   The dialer is in use.

       [ENXIO]   The device doesn’t exist, or there’s no power to it.


4th Berkeley Distribution        May 15, 1985                            DN(4)