HP dat72 5242 User Manual page 65

Section 4: SCSI Bridge Electronics
2.6.5 Setting the Error-Alert (ECC/Rewrite Percentages) Thresholds
The SCSI bridge electronics allow you to set numeric percentage for error-alert thresholds that,
when exceeded, cause the amber LED (the lower LED on the tape drive front panel) to flash. Enter
thresholds by the Numeric Entry method. The rewrite threshold value is set first, followed by the
ECC threshold value. Entries take the form XX.X so you can enter values in the range of 00.0
percent to 99.9 percent. (It is recommended setting this threshold to a value of 10.0 percent.)
Lower values cause the amber LED to light to flash at a lower percentage of error occurrences.
Note:
HP StorageWorks DAT 72 (Models 5242 and 5242-ACL) User's Guide
Because the beginning of tape is written to every time a tape is unloaded, this area of the
tape tends to wear sooner than the rest of the tape. As a result, it is not unusual to
experience rewrites or ECC's at the beginning of tape. If these occur, the predetermined
thresholds can be exceeded early, but the percentage then drops below the threshold as
reading or writing moves further down the tape. To signal this, the error-alert LED
flashes when the error rates exceed the set values but returns to a steady illumination if,
once exceeded, the error rate falls below the set value.
Rwr% 0.5
Ecc:80.5
PRESS to
Alter
Rwr% 0.5 Rwr% 0.5
Ecc:80.5
Ecc:80.5
PRESS to
PRESS to
Incremnt
Incremnt
Rwr%30.7
Ecc:80.5
PRESS to
Alter
Rwr%30.7 Rwr%30.7
Ecc:24.5
Ecc:20.5
PRESS to
PRESS to
Incremnt
Incremnt
Rwr%30.7
Ecc:24.2
PRESS if
Done
Figure 59 Setting error-alert (ECC/Rewrite percentages) thresholds
Rwr%30.5
Ecc:80.5
PRESS to
Incremnt
Rwr%30.7
Ecc:24.2
PRESS to
Incremnt
58 HP Part Number 528296-03 July 2005