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HP Q153090901 User Manual

Page 95

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MODE SELECT 15h/55h

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MODE SELECT

This flag can be used to switch the drive between normal operation and

CD-ROM emulation mode:

If this bit is set to its existing value, there is no change.

If this bit is changed from 0 to 1, the drive will enter CD-emulation

mode. It will change its Inquiry and Mode data appropriately and

cache the first 250 KB of the CD image off tape. CD-ROM support

commands will be enabled. This transition is primarily present to

support automated functional testing.If the bit is changed from 1 to

0, the drive leaves CD-ROM emulation mode and reverts to normal

tape drive mode.

If this bit is changed from 1 to 0, the drive will leave CD-emulation

mode. The Inquiry and Mode data will revert to that for a tape drive

and CD-ROM command support will stop. The tape will be reloaded

and the logical position will be BOP. Backup applications can use

this transition to switch to a normal mode of operation for file system

recovery off tape. Note that operating systems that pre-load class

drivers at boot might not be prepared to talk to the erstwhile CD-

ROM drive