Sony SDX-800V/R manual Tape Log Page Sony Unique, Tape Log Bit Byte Reserved Code 30h, Length 98h

6.Command Specification LOG SENSE

6.6.7. Tape Log Page (Sony Unique)

This page is a Sony unique page which provides information on the tape currently being used. This log cannot be cleared and has the following format:

Table 6-21: Tape Log Page

Bit	7	6	5	4		3		2	1	0
Byte
0	Reserved			Page Code (30h)
1				Reserved
2	(MSB)			Page Length (98h)
3										(LSB)
4	(MSB)			Parameter Code
5
6	DU (0)	DS (1)	TSD (0)	ETC (0)			TMC (00)		LBIN (0)	LP (0)
7				Parameter	Length (m)
8				Parameter Value
3+m

This page is used to return Tape Log information to the host in a format which conforms to the LOG SENSE command page format.

Supported Parameter Codes in this page are listed below along with their meanings:

Table 6-22: Tape Log parameter codes

Parameter Code	Description	Length
001h	Current Groups Written	8
002h	Current Rewritten Tracks	8
003h	Current Groups Read	8
004h	Current C3 ECC Count	8
005h	Previous Groups Written	8
006h	Previous Rewritten Tracks	8
007h	Previous Groups Read	8
008h	Previous C3 ECC Count	8
009h	Total Groups Written	8
00Ah	Total Rewritten Tracks	8
00Bh	Total Groups Read	8
00Ch	Total C3 ECC Count	8
00Dh	Load Count	4

This information is contained within RAM in the Drive Controller. The log is updated as the tape is used.

The term 'current' refers to information generated during the current load of the tape; 'previous' refers to information generated during the last tape load; 'total' refers to information generated during the life of the tape since it was first initialized including the current load.

Use: An estimate of reading and writing performance can be made by the ratios of 'Total Groups Written' to 'Rewritten Tracks' and 'Groups Read' to 'C3 ECC Count'. An indication of tape degradation can be gained by comparing these ratios for 'current', 'previous' and 'total' entries.

Any attempt to change this page using LOG SELECT will result in a CHECK CONDITION with a Sense Key of ILLEGAL REQUEST. The current cumulative values will be returned regardless of the Page Control field in the LOG SENSE CDB.

6-24 SONY AIT-3Ex drive SDX-800V series Ver.1.1