Write, Read, And Verify Error Counter Pages (02H, 03H, And 05H) - Seagate SCSI Interface Product Manual

SCSI Interface Product Manual, Rev. J
The page code assignments for the log pages are listed in Table 73. Detailed descriptions follow the table.
Table 73: Log Page codes
Page Code Description
02h Error Counter page (Write)
03h Error Counter page (Read)
05h Error Counter page (Verify)
06h Non-Medium Error page
37h Cache Statistics page
3Eh Factory Log page
5.8.1

Write, Read, and Verify Error Counter pages (02h, 03h, and 05h)

Table 74 defines the Parameter Code field for the write, read and verify error counter pages.
Table 74: Write, Read, and Verify Errors Parameter Code field (02h, 03h, and 05h)
Bit 7
Byte
0 0
1 Parameter Code [1]
Notes.
[1] Parameter codes 00h through 06h specify six counters each for write, read, and verify errors (18
counters). A description of the type (category of error) counters specified by codes 00h through 06h are
described following.
00h Error Corrected Without Substantial Delay. An error correction was applied to get perfect data
(a.k.a., ECC on-the-fly). "Without Substantial Delay" means the correction did not postpone read-
ing of later sectors (e.g., a revolution was not lost). The counter is incremented once for each logi-
cal block that requires correction. Two different blocks corrected during the same command are
counted as two events.
01h Error Corrected With Possible Delays. An error code or algorithm (e.g., ECC, checksum) is applied
in order to get perfect data with substantial delay. "With possible delay" means the correction took
longer than a sector time so that reading/writing of subsequent sectors was delayed (e.g, a lost
revolution). The counter is incremented once for each logical block that requires correction. A
block with a double error that is correctable counts as one event and two different blocks corrected
during the same command count as two events.
02h Total (e.g., re-writes or re-reads). This parameter code specifies the counter counting the number
of errors that are corrected by applying retries. This counts errors recovered, not the number of
retries. If five retries were required to recover one block of data, the counter increments by one,
not five. The counter is incremented once for each logical block that is recovered using retries. If
an error is not recoverable while applying retries and is recovered by ECC, it isn't counted by this
counter; it will be counted by the counter specified by parameter code 01h–Error Corrected With
Possible Delay.
03h Total Error Corrected. This counter counts the total of parameter code errors 00h, 01h, and 02h.
There is to be no "double counting" of data errors among these three counters. The sum of all cor-
rectable errors can be reached by adding parameter code 01h and 02h errors, not by using this
total.
Section
5.8.1
5.8.1
5.8.1
5.8.2
5.8.3
5.8.4
6 5
0 0
Page
107
107
107
108
108
109
4 3
0 0
2 1
0 0
107
0
0