Disclosed is a method of access control for a disk drive whereby an access
operation for, particularly, sequentially and alternately executing accesses is
supported. A CPU of the present disk drive sequentially and alternately executes
accesses to a plurality of data tracks on a disk in response to an access request
generated from a host system. During the access operation, the CPU secures time
for a look-ahead operation, the time corresponding to the difference between transfer
rates. Thus, sequential and alternate access operation in which the number of seek
operations can be reduced can be realized.
