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Sequential writing is performed without waiting for rotation.
"0" : This prohibits operation of the WRITE cache function.
WRITE DATA remains in the buffer memory, the cache is not made the object even for a read
command, and as soon as all the data has been written to the disk, "GOOD" status is reported.
d. SIZE (size enable)
"1" : Divides the data buffer in accordance with the value specified for the cache segment
size (bytes 14, 15).
"0" : Divides the data buffer in accordance with the value specified for the number of
cache segments (byte 13).
This bit cannot be changed. The IDD disregards the specification in this bit and operates
according to the "Default" value (= "0").
e. DISC (discontinuity)
"1" : Even if a track switch occurs during Look-Ahead, the Look-Ahead operation
continues without interruption.
"0" : Look-Ahead is terminated at the point where track switch occurs during Look-Ahead.
This bit cannot be changed. The IDD disregards the specification in this bit and operates
according to the "Default" value (= "1").
f. IC (initiator control enable)
"1" : Dividing of cache segments is according to the SIZE bit specification.
"0" : Dividing of the cache segments is performed by an algorithm that is inherent in the IDD.
This bit cannot be changed. The IDD disregards the specification in this bit and operates
according to the "Default" value (= "1").
g. Pre-fetch Inhibit Block Count
This parameter is used to selectively prohibit data Look-Ahead operations in the READ
command or the READ EXTENDED command.
specified in the CDB of the READ command or the READ EXTENDED command is
greater than the value in this parameter, data Look-Ahead operations are not executed in
that command. This bit cannot be changed. The IDD disregards the specification in this bit
and operates according to the "Default" value (= X 'FFFF').
h. Minimum Pre-fetch
This parameter specifies the minimum quantity of logical data blocks pre-fetched to the
data buffer with the READ command or READ EXTENDED command.
This parameter cannot be changed. The IDD disregards the specification in this field.
3 - 48
When the "Transfer block count"
C141-E039-01EN
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