Toshiba 4006GAH Computer Drive User Manual


 
360050398
Toshiba Corporation Digital Media Network Company
Page 126 of 157
© 2005, Copyright TOSHIBA Corporation All Rights Reserved
10.8.43.2.2 Error log index
The error log index indicates the error log data structure representing the most recent error. If there have been
no error log entries, the error log index is cleared to zero. Valid values for the error log index are zero to 255.
10.8.43.2.3 Extended Error log data structure
The error log is viewed as a circular buffer. When the last supported error log sector has been filled, the next
error shall create an error log data structure that replaces the first error log data structure in sector zero. The
next error after that shall create an error log data structure that replaces the second error log data structure in
sector zero. The fifth error after the log has filled shall replace the first error log data structure in sector one, and
so on.
The error log index indicates the most recent error log data structure. Unused error log data structures shall be
filled with zeros.
The content of the error log data structure entries is defined in the following table.
Extended Error log data structure
Byte Descriptions
n thru n+17 First command data structure
n+18 thru n+35 Second command data structure
n+36 thru n+53 Third command data structure
n+54 thru n+71 Fourth command data structure
n+72 thru n+89 Fifth command data structure
n+90 thru n+123 Error data structure
10.8.43.2.3.1 Command data structure
The fifth command data structure shall contain the command or reset for which the error is being reported. The
fourth command data structure should contain the command or reset that preceded the command or reset for
which the error is being reported, the third command data structure should contain the command or reset
preceding the one in the fourth command data structure, etc. If fewer than four commands and resets preceded
the command or reset for which the error is being reported, the unused command data structures shall be zero
filled, for example, if only three commands and resets preceded the command or reset for which the error is
being reported, the first command data structure shall be zero filled. In some devices, the hardware
implementation may preclude the device from reporting the commands that preceded the command for which
the error is being reported or that preceded a reset. In this case, the command data structures are zero filled.
If the command data structure represents a command or software reset, the content of the command data
structure shall be as shown in the following table. If the command data structure represents a hardware reset,
the content of byte n shall be FFh, the content of bytes n+1 through n+13 are vendor specific, and the content of
bytes n+14 through n+17 shall contain the timestamp.