UU(4) BSD/vax Kernel Interfaces Manual UU(4)NAMEuu — TU58/ DECtape II UNIBUS cassette interface
device uu0 at uba0 csr 0176500 vector uurintr uuxintr
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(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 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.
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.
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 TU58 was sending a contin‐
uous break signal and had to be reset. This may indicate a hardware prob‐
lem, 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
indicating a hard error. The actual error code is shown in octal. No
retries are attempted by the driver.
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 ALSOtu(4), arff(8)HISTORY
The uu driver appeared in 4.2BSD.
4.2 Berkeley Distribution June 5, 1993 4.2 Berkeley Distribution