HP Q153090901 - Manual (Page 68)

Commands 68
Tape Capacity log page
The Tape Capacity log page code is 31h. The Page Length is 20h. There are four parameters, 1
through 4. Parameters 2 and 4 are not supported and are returned as zero. All parameters are 4
bytes long. All parameters are in megabytes (1,048,576 bytes) and assume no compression. This
data relates to the current tape and can be neither reset nor written.
The supported parameters are as follows:
Data Compression log page
The Data Compression log page code is 32h and the page length is 4Ch. There are ten
parameters, 0 through 9. Parameters 0 and 1 are two bytes long. Parameters 2 through 9 are
each 4 bytes long.
The supported fields are listed below. Parameters 2 through 9 occur as pairs that represent a large
number of bytes transferred. The first four-byte parameter represents the number of whole
megabytes transferred, rounded to the nearest megabyte. The second four-byte parameter
represents the difference between this number of megabytes and the actual number of bytes. This
may be a signed quantity.
This data relates to the current tape and is cleared at the start of tape load. It may not be written.
Parm. Description Length Updated When
1 Main Partition Remaining Capacity 4 Data set physically written
2 Alternate Partition Remaining Capacity 4 n/a
3 Main Partition Maximum Capacity 4 If Set Capacity succeeds
4 Alternate Partition Maximum Capacity 4 n/a
Parameter Description Length Updated When
0 Read compression ratio X 100 2 Data set logically read
1 Write compression ratio X 100 2 Data set logically written
2 Megabytes transferred to host 4 Data set logically read
3 Bytes transferred to host 4 Data set logically read
4 Megabytes read from tape 4 Data set logically read
5 Bytes read from tape 4 Data set logically read
6 Megabytes transferred from host 4 Data set logically written
7 Bytes transferred from host 4 Data set logically written
8 Megabytes written to tape 4 Data set logically written
9 Bytes written to tape 4 Data set logically written