UU(4)                  OpenBSD Programmer's Manual (VAX)                 UU(4)

NAME
     uu - TU58/ DECtape II UNIBUS cassette interface

SYNOPSIS
     options UUDMA
     device uu0 at uba0 csr 0176500 vector uurintr uuxintr

DESCRIPTION
     The uu device provides access to dual DEC TU58 tape cartridge drives con-
     nected to the UNIBUS via a DL11-W interface module.

     The interface supports only block I/O to the TU58 cassettes (see
     physio(9)). 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 TU58 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 TU58 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 en-
     tered 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 TU58 was sending a contin-
     uous 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 ille-
     gal 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 inter-
     rupt 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 in-
     dicating a hard error.  The actual error code is shown in octal.  No re-
     tries are attempted by the driver.

ERRORS
     The following errors may be returned:

     [ENXIO]  Nonexistent drive (on open); offset is too large or bad (unde-


              fined) 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.

OpenBSD 3.0                     March 27, 1991                               2
