Qualstar 34XX Series User Manual page 53

opportunity for tape streaming, and increasing the throughput in systems that
otherwise might not be able to keep up with the drive.
If the system presents the next command to the drive before the extended gap has
been fully traversed, the drive will truncate the unused portion of the extended gap
and use only the minimum necessary to maintain streaming. The actual gap length
will be equal to the system response time multiplied by the tape speed, plus 0.150-
inch. In no case will the IBG be less than 0.6-inch (0.3-inch in GCR).
•
NORMAL
0.3 inches in GCR).
•
- The drive will extend the IBG up to 0.84 inches while writing.
LONG
•
EX-LONG
Extended write gaps reduce the formatted capacity of the tape and are not generally
recommended.
4.3.2.17 WRT PARITY: (Default = Int)
Most tape controllers do not generate the write parity signal and rely on the tape
drive to do so. However, some controllers do generate write parity and send it to the
drive on the IWP interface line. This option allows the tape drive to be compatible
with both versions.
•
- The drive ignores the information on the IWP interface line and generates
INT
its own write parity information.
•
- The host controller must provide the correct write parity signal.
EXT
4.3.2.18 DENSITY: (Default = Read)
This function sets the mode of automatic density selection for the drive. The choices
are MANUAL, LOAD, READ, DUAL, and INITIAL. Detailed information on the
application of this function is given in Section 3.6.
4.3.2.19 NO-ID DEN: (Default = 800)
The NO-ID DENsity parameter sets the detected density when a tape without an ID
burst is loaded.
•
- The drive assumes the tape is an 800 CPI tape and sets the detected
800
density to 800. An asterisk ( * ) indicates that no ID burst was detected. If the
tape is a 3200 CPI tape with no ID burst, attempts to read it will result in hard
errors.
•
- The drive assumes the tape is a 3200 CPI tape and sets the detected
3200
density to 3200. An asterisk ( * ) indicates that no ID burst was detected. If the
tape is an 800 CPI tape, attempts to read it will result in hard errors.
500300 Rev. U
- The IBG is the nominal as specified by ANSI (0.6 inches in PE,
- The drive will extend the IBG up to 12.2 inches while writing.
NOTE
Menu Operations 4-9