Maximum Counts - Quantum LTO 2 User Manual

Maximum Counts

LTO-2 SCSI Interface Guide
The maximum value of each counter depends on the size of the counter in
2
bytes. When the maximum count is reached, the DU bit in the Parameter
Control byte for the counter is set to 1 for the
that the parameter is no longer to be updated by the drive because the
maximum count has been reached and if RLEC (Report Log Exception
Condition) bit in Mode Page 0Ah (Control Mode page) is set to 1,
Recovered Error/Log Counter at Maximum (01/5B/02) is returned to
host to inform of the log exception. Bytes 15-17 of the
data specify the page, MSB and LSB of the Parameter Code respectively,
which caused the Log Exception.
When a counter reaches the maximum, the counter is no longer
incremented. If a maximum value for the parameter size is reached, the
count does NOT roll over and continue counting. When any counter of a
page reaches maximum, all counters of that page are no longer
incremented. A
LOG SELECT
and 32h with the PCR bit set to reset the accumulated values and to allow
counters to continue as normal. The DU bit of the affected parameter is
also reset to zero. The same effect can be achieved by a SCSI Bus Reset,
Bus Device Reset, or cartridge loading.
Chapter 2 SCSI Commands
LOG SELECT Command
LOG SENSE
command can be issued for pages 02h, 03h,
data indicating
REQUEST SENSE
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