4.1cBSD/usr/man/man4/tu.4v

.TH TU 4V "9 February 1983"
.UC 4
.SH NAME
tu \- VAX-11/730 TU58 console cassette interface
.SH DESCRIPTION
The
.I tu
interface provides access to the VAX 11/730 TU58 console
cassettes.  It could, conceivably, also provide access to
the VAX 11/750 TU58 console cassette, but due to flow control
problems in the host-TU58 interface access to the 11/750
console storage device is unreliable.
.PP
The interface supports only raw i/o to the TU58 cassettes.
The devices are normally manipulated with the 
.IR arff (8V)
program using the `m' option.
.PP
The device driver is automatically configured when a
system is configured to run on an 11/730 or 11/750.
.SH FILES
.B /dev/tu0
.br
.B /dev/tu1
.SH "SEE ALSO"
arff(8V)
.SH DIAGNOSTICS
.BR "tu: no bp, active %d" .
A transmission complete interrupt was received with no outstanding
i/o request.  This indicates a hardware problem.
.PP
.BR "neither data nor end: %o %o" .
A response from the TU58 indicated neither data to be received
nor completion of a control operation.  Usually seen when this
driver is used on an 11/750.
.PP
.BR "tu protocol error, state=%s, op=%x, cnt=%d, block=%d" .
The driver entered an illegal state.  The information printed
indicates the illegal state, operation currently being executed,
the i/o count, and the block number on the cassette.
.PP
.BR "tu 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.
.PP
.BR "tu: read stalled" .
The device did not respond to a read request after 400
milliseconds.  This is very common when attempting to use
the driver on an 11/750.
.PP
(to the user)
.br
.BR "tu%d: %d soft errors, %d chksum errors, %d hard errors" .
This is printed on the user's terminal on closing the device.
.SH BUGS
There should be a useable version of this driver for the
11/750.