Fujitsu MBC2036RC, MBC2073RC, MBA3300RC, MBA3147RC Look-Ahead Cache Feature, Disabling caching data

3.2 Look-Ahead Cache Feature

a)Data read by a READ or a READ EXTENDED command and which have been read to the data buffer by Look-Ahead are data which are objects of caching. Depending on the timing for halting Look-Ahead, it is possible that data read by the READ command will be overwritten by Look-Ahead.

b)Data which have been hit by the READ or READ EXTENDED command and transferred to the INIT once are also objects of caching as long as they are not invalidated.

c)Data transferred from the INIT and written to the disk media by the WRITE and WRITE EXTENDED, command are objects of caching.

d)Data transferred from the INIT and written to the disk media by WRITE AND VERIFY command is not the objects of caching.

(3) Disabling caching data

Various data which are objects of caching in the data buffer are disabled in the following cases.

a)If any of the following commands is issued for the same data block as data which are the object of caching, that data block ceases to be an object of caching.

−WRITE

−WRITE EXTENDED

−WRITE AND VERIFY

b)If any of the following commands is issued, all the data which are objects of caching are disabled.

−LOG SELECT

−MODE SELECT

−MODE SENSE

−READ BUFFER

−READ DEFECT DATA

−READ LONG

−RECEIVE DIAGNOSTIC RESULTS

−SEND DIAGNOSTIC

−START/STOP UNIT

−WRITE LONG

−FORMAT UNIT

−LOG SENSE

−MODE SELECT EXTENDED

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