NAME
mt —
TM78/ TU-78 MASSBUS magtape
interface
SYNOPSIS
mt* at mscpbus? drive?
DESCRIPTION
The TM78/ 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
- mu0: 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.
- mu0: 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.
- mu0: 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.
- mu0: hard error bnN mbsr=... er=X ds=....
- 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.
- mu0: blank tape.
- An attempt was made to read a blank tape (a tape without even end-of-file marks).
- mu0: 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
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.