Mo Write Cache - Fujitsu MCE3064AP Product Manual

When the cache is enabled, the buffer contains data transferred from the host with a write
command. If a read command is issued to the sector address at this time, the ODD directly
transfers data to the high-level equipment from the data buffer without reading it from media. If
the cache is hit with a read command, the ODD makes the data in the hit segment being kept in the
highest priority.
The data listed below cannot be stored in the read cache.
!
Data once transferred to the host during prereading
!
Data read before hardware reset, software reset, DEVICE RESET command is received, or
power-off
!
Data already stored before media is mounted
All buffer data is discarded under the following conditions:
!
Hardware reset, software reset, DEVICE RESET command is received, or power-off
!
When media is ejected
!
When the FORMAT UNIT command is received
!
In standby mode
!
In sleep mode
!
When the system receives a command (such as MODE SELECT and SET FEATURES) that
may change the operating mode
4.4.5.3

MO write cache

When the write cache is enabled, the ODD responds to the host with command end. This occurs
when the data transfer is done with the WRITE (10), WRITE (12), or WRITE AND VERIFY
command (hereafter "Write command" in this document). If Write commands are continuously
issued, the ODD responds to the host with command end when the data transfer is completed. This
occurs if the specified sector is continuous from the sector specified by the previous command.
The ODD writes data kept in the buffer to media under the following conditions:
!
When data can be written on media during data transfer with a Write command or while the
ODD is waiting for a command
!
When a command that requires a new segment is received while all segments in the data buffer
are used
!
When the Eject switch is pressed
!
When the SYNCHRONIZE CACHE command is received/DEVICE RESET command is
received
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