Operating instructions

8-4
SCSI REFERENCE 1012975
CHAPTER 8—LOG SENSE (4Dh)
8.3 WHAT THE AUTOLOADER RETURNS
This section describes the log page structure and the log pages that the
autoloader supports. The LOG SENSE command returns a single log page
specified in the Page Code field of the CDB. Each log page begins with a
four-byte page header (bytes 00 through 03), followed by zero or more
variable-length log parameters defined for that page.
Page Code – Byte 00, Bits 0 through 5
The Page Code field identifies which log page is being transferred. This field
contains one of the codes described in Ta b l e 8 - 1 .
Page Length – Bytes 02 and 03
The Page Length field specifies the length, in bytes, of the following Log
Parameters. The value returned for this field depends on the value you
specified for the Page Code and the Parameter Pointer in the CDB. This value
is independent of what you specified for the Allocation Length.
Log Parameters – Bytes 04 through n
Log parameters are data structures that are contained in log pages and can be
one of the following:
 Data counters that record a count of a particular event
 A numeric value indicating the state of the autoloader hardware
 A string that contains the autoloader event history
The general format of a log parameter is shown on the following section.
Bit
Byte
7 6 5 4 3 2 1 0
00 Reserved Page Code
01 Reserved
02 (MSB)
Page Length
(LSB)
03
04
Log Parameter (First)
...
Log Parameter (Last)
...
n