MT(4)                                                                    MT(4)



NAME
       mt - TM78/TU-78 MASSBUS magtape interface

SYNOPSIS
       master mt0 at mba? drive ?
       tape mu0 at mt0 slave 0

DESCRIPTION
       The  tm78/tu-78 combination provides a standard tape drive interface as
       described in _m_t_i_o(4).  Only 1600 and 6250 bpi are supported; the  TU-78
       runs at 125 ips and autoloads tapes.

SEE ALSO
       mt(1), tar(1), tp(1), mtio(4), tm(4), ts(4), ut(4)

DIAGNOSTICS
       mu%d:  no  write  ring.  An attempt was made to write on the tape drive
       when no write ring was present; this message is written on the terminal
       of the user who tried to access the tape.

       mu%d:  not online.  An attempt was made to access the tape while it was
       offline; this message is written on the terminal of the user who  tried
       to access the tape.

       mu%d:  can’’t  change density in mid-tape.  An attempt was made to write
       on a tape at a different density than is already recorded on the  tape.
       This message is written on the terminal of the user who tried to switch
       the density.

       mu%d: hard error bn%d mbsr=%b er=%x ds=%b.   A tape error  occurred  at
       block  _b_n;  the mt error register and drive status register are printed
       in octal with the bits symbolically decoded.  Any  error  is  fatal  on
       non-raw  tape; when possible the driver will have retried the operation
       which failed several times before reporting the error.

       mu%d: blank tape.  An attempt was made to read a  blank  tape  (a  tape
       without even end-of-file marks).

       mu%d: offline.  During an i/o operation the device was set offline.  If
       a non-raw tape was used in the access it is closed.

BUGS
       If any non-data error is encountered on non-raw tape, it refuses to  do
       anything more until closed.

       Because 800 bpi tapes are not supported, the numbering of minor devices
       is inconsistent with triple-density tape units.  Unit  0  is  drive  0,
       1600 bpi.



4th Berkeley Distribution        June 1, 1986                            MT(4)