公开(公告)号：JPH07210975A

公开(公告)日：1995-08-11

申请号：JP23470694

申请日：1994-09-29

Applicant: IBM

Inventor： KURISUTOFUAA EICHI BAJIYOREKU ,  TOOMASU DABURIYU GUREISAA ,  KURAASU BERENDO KURAASEN ,  CHIYAARUZU AARU NIIRUSEN ,  JIYOOJI AARU SANTANA ,  GOODON JIEEMUZU SUMISU ,  DEIBITSUDO AREN TONPUSON ,  MAIKERU RII UOOKUMAN

IPC: G06F1/32 ,  G11B19/00 ,  G11B19/20

Abstract: PURPOSE: To apply timing for reducing power consumption in relation to the latest history of an access operation to a device by comparing average consumption energy with a previously decided consumption energy threshold and selecting an operation mode. CONSTITUTION: A disk driving device 20 receives power from a power source device 22 through a mode controller 24. The power from the device 22 is transferred to a consumption energy monitor device 28 through a line 26 and is transferred from the device 28 to the controller 24 through a line 30. The controller 24 distributes the power inputted through the line 30 to the device 20 through plural lines represented by a line 32. The device 28 gives the signal 34 of use energy to the consumption energy comparator 36 of fuzzy logic and compares average consumption energy with the consumption energy threshold. The comparator 36 generates a mode selection signal 38 based on the compared result and transfers the signal 38 to the controller 24 for making a necessary power consumption reduction mode. The controller 24 selects the operation mode in response to the signal 38.

公开(公告)号：JPH05151727A

公开(公告)日：1993-06-18

申请号：JP13272292

申请日：1992-05-25

Applicant: IBM

Inventor： TOOMASU CHIYAARUZU KURISUTENSE ,  MASHIYUU UIRIAMU RUUKU ,  MAIKERU RII UOOKUMAN

IPC: G11B21/10 ,  G11B5/55 ,  G11B7/13 ,  G11B20/10 ,  G11B20/18

Abstract: PURPOSE: To speedily measure the error in the position of a detector and to precisely fix it by measuring the error rate of written data as the function of the reading offset of the detector, so as to detect the thermal and mechanical error of a data detector. CONSTITUTION: A detection element 12 reads data from a recording medium, and its output signal is inputted to a data detection and synchronizing circuit 33, through a preamplifier 35 to read the content of the data from the signal. The data is sent to a microprocessor 25 by detecting the error of a data block by an ECC detection correcting device 23 and counting the number of errors by a counter 29. The processor 25 calculates the error rate as a function of the reading offset of the detector 12, decides the radial directional position of the detector 12 and places the detector 12 at the center position on a track through a positioning mechanism 21, to compensate for the thermal and mechanical error of the detector 12.