User guide

SC3500 User Guide Ver 1.3 March 8, 2005 Page 18 of 28
3.3.15 Erase Command
Erase CDB
The ERASE (10) command requests that the target erase the specified number of
blocks starting at the specified logical block address on the medium. As used here,
erased means the medium shall be erased. The previous data recorded on the
medium, if any, shall not be recoverable. The Remap Table is retained, thus allowing
write and read access to the memory.
The erase all (ERA) bit set to one indicates that all blocks on the medium shall be
erased. If the ERA bit is set to one and if the number of blocks is not zero, the SC3500
will return CHECK CONDITION, and the sense key shall be set to ILLEGAL REQUEST,
with an additional sense code of INVALID FIELD IN CDB. If the ERA bit is zero a
transfer length of zero indicates that no blocks shall be erased. This condition is not
considered an error and no data is erased. Any other value indicates the number of
logical blocks that shall be erased.
A note about the Erase Command –
The erase command has been implemented as a security erase mechanism on the
SC3500. The command was originally created and used by tape backup devices.
When executed with ERA set, a 1 Gbyte drive can be wiped clean in about 10 seconds.
All storage locations on the drive are erased, including both user and system
(protected) data areas. At the conclusion of the erase command, the existing Remap
Table™ is restored to memory.