NAME
mt —
TM-78/TU-78 MASSBUS mag tape
interface
SYNOPSIS
mt0 at mba? drive ? tape mu0 at mt0 slave 0
DESCRIPTION
The TM-78/TU-78 combination provides a standard tape drive interface as
described in
mtio(4). Only 1600
and 6250 BPI are supported; the TU-78 runs at 125 IPS and autoloads tapes.
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 bn; 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.
SEE ALSO
tar(1),
mt(1),
mtio(4),
vax/tm(4),
vax/ts(4),
vax/ut(4)
HISTORY
The
mt driver appeared in
4.1BSD.
BUGS
If a physical error (non-data) occurs,
mt may hang
ungracefully.
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.