The cpqs driver controls the obsolete Compaq CPQS
tape adapter and tape compression adapter. These tape drives use
a different set of device name conventions from those
for SCSI tape drives (described on
The device node format for accessing a DAT or 320/525 tape drive
where # is the target ID of the tape drive (0-4).
The following table describes the available options:
Access the tape drive using the compression chip on the tape adapter.
To use this option, no other drives on the adapter can be in use
by other processes. Once a drive is being
accessed using the compression chip, the other drives on the adapter
cannot be used until the process using the compression mode
closes the tape drive.
Immediate mode. Certain commands, like erase or retension will return
to the application program before the command actually finishes on the
No rewind. A rewind command will not be issued to the drive when the
device is closed.
Access the tape in QIC-150 density. This option is
only relevant on a 320/525 tape drive.
The auto-density mode selects the format to match the data
on the media for reading. The highest density for the
media type present is selected for writing. On the 320/525
tape drive, the QIC-150 mode is used to force
QIC-150 format when writing on high density media
so that the tape can be read on 150/250 type drives. If a
6150 or 6250 tape media is used, the drive writes
QIC-150 format in the auto-density mode.
On both a DAT and 320/525 tape drive, immediate mode
returns without waiting for the command to complete,
which is useful for executing retension and erase tape commands.
Compaq tape formats
The Compaq CPQS adapter and 320/525
CPQS tape drive support the following tape formats:
The default device automatically determines the tape
format to use. For reading, the data written on the tape
media determines the tape density and format. The media
type determines the default on write operations; that is,
the highest density for the type of media present is written.
If you want to use a lower tape density, use a device
type that explicitly selects lower density.
The following error messages may be displayed on the console.
for general information about kernel error messages,
including a list of generic device driver errors.
NOTICE: cpqs: Adapter timed out, status=0xn
The adapter reset routine timed out after 30 seconds; the adapter failed
NOTICE: cpqs: Adapter self test failed, status=0xn
The adapter registered an internal error while it was being reset.
NOTICE: cpqs: Bad device type n in device major/minor ioctl
command was used on the device.