NAME
uu
-
TU-58/DECtape II UNIBUS
cassette interface
SYNOPSIS
options UUDMA
uu0 at uba0 csr 0176500 vector uurintr uuxintr
DESCRIPTION
NOTE: This driver has not been ported from
4.4BSD
yet.
The
uu
device provides access to dual
DEC
TU-58
tape cartridge drives
connected to the
UNIBUS
via a
DL-11W
interface module.
The interface supports only block
I/O
to the
TU-58
cassettes (see
physio(4)).
The drives are normally manipulated with the
arff(8)
program using the ``m'' and ``f'' options.
The driver provides for an optional write and verify
(read after write) mode that is activated by specifying the
``a'' device.
The
TU-58
is treated as a single device by the system even
though it has two separate drives,
`
uu0
'
and
`
uu1
'.
If there is
more than one
TU-58
unit on a system, the extra drives
are named
`
uu2
',
`
uu3
'
etc.
NOTES
Assembly language code to assist the driver in handling
the receipt of data (using a pseudo-DMA approach) should
be included when using this driver; specify
`
options
UUDMA
'
in the configuration file.
FILES
/dev/uu?
-
/dev/uu?a
-
DIAGNOSTICS
- uu%d: no bp, active %d.
-
A transmission complete interrupt was received with no outstanding
I/O
request. This indicates a hardware problem.
- uu%d protocol error, state=%s, op=%x, cnt=%d, block=%d.
-
The driver entered an illegal state. The information printed
indicates the illegal state, the
operation currently being executed,
the
I/O
count, and the block number on the cassette.
- uu%d: break received, transfer restarted.
-
The
TU-58
was sending a continuous break signal and had
to be reset. This may indicate a hardware problem, but
the driver will attempt to recover from the error.
- uu%d receive state error, state=%s, byte=%x.
-
The driver entered an illegal state in the receiver finite
state machine. The state is shown along with the control
byte of the received packet.
- uu%d: read stalled.
-
A timer watching the controller detected no interrupt for
an extended period while an operation was outstanding.
This usually indicates that one or more receiver interrupts
were lost and the transfer is restarted.
- uu%d: hard error bn%d, pk_mod %o.
-
The device returned a status code indicating a hard error. The
actual error code is shown in octal. No retries are attempted
by the driver.
ERRORS
The following errors may be returned:
- [
ENXIO
] -
Nonexistent drive (on open);
offset is too large or bad (undefined)
ioctl(2)
code.
- [
EIO
] -
Open failed, the device could not be reset.
- [
EBUSY
] -
Drive in use.
SEE ALSO
tu(4),
arff(8)
HISTORY
The
uu
driver appeared in
4.2BSD.