US 7,486,458 B2
Magnetic disk drive with diagnosis of error-correcting retries
Sumie Takeda, Kanagawa (Japan); Akira Kojima, Kanagawa (Japan); Mitsuharu Horiuchi, Kanagawa (Japan); and Shinichi Kobayashi, Kanagawa (Japan)
Assigned to Hitachi Global Storage Technologies Netherlands B.V., AZ Amsterdam (Netherlands)
Filed on Jan. 27, 2005, as Appl. No. 11/46,322.
Claims priority of application No. 2004-032788 (JP), filed on Feb. 10, 2004.
Prior Publication US 2005/0174677 A1, Aug. 11, 2005
Int. Cl. G11B 27/36 (2006.01); G11B 5/09 (2006.01)
U.S. Cl. 360—31  [360/53; 714/705] 18 Claims
OG exemplary drawing
 
1. A magnetic disk drive having a mechanism to receive a command from an upper system and transmitting an error, the magnetic disk drive comprising:
a disk
a motor to rotate the disk;
a head to read signals from or write signals to the disk;
a control system to control the motor and the head for reading signals from or writing signals to the disk and to control interface between the magnetic disk drive and the upper system;
a processor coupled with the control system, the processor having two operation modes including a normal operation mode and a pseudo failure mode in which a pseudo error is reported;
a selection device to allow selection of one of the two operation modes of the processor; and
a mechanism to specify in the pseudo failure mode what type of pseudo error is to occur, how many times the pseudo error is to repeat before recovery, the number of times of recovery, and where the pseudo error is to occur.