Disk drive system controller architecture utilizing embedded real-time diagnostic monitor

• US 4,979,055 A
• Filed: 10/18/1989
• Issued: 12/18/1990
• Est. Priority Date: 06/02/1987
• Status: Expired due to Term

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Conner Peripherals Incorporated (Whitehouse Group Ltd.)
• Inventors: Squires, John P., Shrinkle, Louis J., Fiers, Thomas A.
• Primary Examiner(s): HEINZ, ALLEN J
• Application Number:
  US07/423,719
• Time in Patent Office: 426 Days
• Field of Search: 360/69-72.1, 360/73.01, 360/73.03, 360/75, 360/77.02, 360/78.04
• US Class Current: 360/69
• CPC Class Codes: G06F 11/22 Detection or location of defective computer hardware by testing during standby operation or during idle time, e.g. start-up testing
• CPC Class Codes: G06F 11/2205 using arrangements specific to the hardware being tested
• CPC Class Codes: G06F 11/32 with visual or acoustical indication of the functioning of the machine
• CPC Class Codes: G11B 19/02 Control of operating function, e.g. switching from recording to reproducing
• CPC Class Codes: G11B 19/28 Speed controlling, regulating, or indicating G11B19/24 takes precedence
• CPC Class Codes: G11B 27/36 Monitoring, i.e. supervising the progress of recording or reproducing for digital recording G11B20/00 and s.gr.; for monitoring, testing or measuring of TV recorders of the type covered by H04N5/76 and subgroups, see H04N17/06
• CPC Class Codes: G11B 33/10 Indicating arrangements; Warning arrangements G11B15/04, G11B19/04, G11B27/34, G11B27/36 take precedence
• CPC Class Codes: Y10S 360/902 Storage density, e.g. bpi, tpi
• CPC Class Codes: Y10S 360/904 Weight

Abstract

A disk drive control architecture provides for the storage and retrieval of data with respect to a rotating media and for the transfer of data with respect to a host in response to host commands. The control architecture provides for the execution of a plurality of background processes for controlling the spin speed of the rotating media, controlling the positioning of the sensor and controlling the reading and writing of data with respect to the rotating media. The control architecture further provides for foreground processes for controlling the background processes. The foreground processes include an interface task, for coordinating the background processes in the execution of host commands and a monitor task integral to the interface task such that the monitor task is capable of implementing diagnostic commands capable of accessing all of the resources of the control architecture. The transfer of diagnostic commands and resultant diagnostic information may be directed through a dedicated data communications channel separate from the data channel used for the transfer of commands and data with respect to the host.

Claims

1. A control architecture that provides for the storage and retrieval of data with respect to a rotating media and transfer of data with respect to a host in response to host commands, wherein the data is read and written by a sensor with respect to the rotating media, said control architecture comprising:

(a) a microcontroller; and

(b) a memory containing a control program, said memory being coupled to said microcontroller to permit execution of said control program by said microcontroller, the execution of said control program providing for the performance of a plurality of microcontroller control processes including;

(i) a plurality of first control processes including a spin control process for controlling the spin speed of the rotating media, a positioning control process for controlling the positioning of said sensor and a read/write control process for controlling the reading and writing of data with respect to said rotating media; and

(ii) a plurality of second control processes for controlling said first control processes, said second control processes including an interface control process for controlling said first control processes in the execution of host commands and a monitor control process for the execution of diagnostic commands for controlling said first control processes independent of said host.

2. The control architecture of claim 1 wherein data is stored by said rotating media in concentric tracks, wherein each track includes a plurality of consecutive sectors, wherein the time required for a predetermined sector to pass by said sector defines a sector period, wherein said first control processes are performed by said microcontroller during each of a series of consecutive sector periods, wherein said memory includes a plurality of predetermined data storage locations, wherein said microcontroller performs said first control processes dependant on data values programmed into said plurality of predetermined data storage locations, and wherein said interface and monitor control processes control said first control processes by programming predetermined data values into said plurality of predetermined data storage locations.

3. The control architecture of claim 1 or 2 wherein said memory includes a plurality of reprogrammable, non-volatile data storage locations, wherein said second control processes provide for programming of the data values programmed into said non-volatile data storage locations to pre-selected ones of said predetermined data storage locations, and wherein said second control processes provide for the reprogramming of said non-volatile data storage locations with the data values programmed into said pre-selected ones of said predetermined data storage locations.

4. The control architecture of claim 3 wherein the execution of said control program is initiated by execution of an initialization process including a dispatch sub-process, execution of said dispatch sub-process by said microcontroller selecting one of said second control processes for execution dependent on an age data read from a predetermined reprogrammable, non-volatile data storage location of said memory, said microprocessor selecting said monitor control process for execution in response to the reading of a first predetermined age data value and said interface control process for execution in response to the reading of a second predetermined age data value.

5. The control architecture of claim 4 wherein said monitor control process includes a plurality of diagnostic sub-processes and wherein said dispatch sub-process further selects ones of said diagnostic sub-processes for execution in response to the reading of respective predetermined age data values from said predetermined reprogrammable, non-volatile data storage location of said memory, wherein said diagnostic subprocesses provide for the selective programming of data values into said plurality of predetermined data storage locations and for the reprogramming of the data value stored in said predetermined reprogrammable, non-volatile data storage location of said memory.

6. A disk drive comprising:

(a) a disk for storing data in a plurality of concentric tracks on a surface of said disk and within a track band defined by predetermined inner and outer diameter tracks;

(b) a transducer for reading data from said disk;

(c) a spin motor, coupled to said disk, for rotating said disk;

(d) an actuator, coupled to said transducer, for positioning said transducer relative to said tracks; and

(e) control means for providing communication signals to control the commutation of said spin motor and positioning signals to said actuator to control the positioning of the transducer, said control means including a microcontroller for executing a control program and a memory coupled to said microcontroller and providing for the storage of said control program, said memory further providing for the non-volatile storage of initialization data values;

wherein execution of said control program by said microcontroller provides for performance of a control process for operating said disk drive dependent on a predetermined initialization data value stored by said memory, the performance of said control process further determining a revised initialization data value and replacing said predetermined initialization data value with said revised initialization data value in said memory.

7. The disk drive of claim 6 wherein said positioning control process is a positioning control process for positioning said transducer with respect to a predetermined track, wherein said positioning control process utilizes said predetermined initialization data as a constant in a positioning algorithm performed by said positioning control process.

8. The disk drive of claim 7 wherein said initialization data value is a predetermined plurality of position algorithm initialization data values respectively corresponding to a plurality of subbands of said track band, wherein each said subband consists of one or more concentric tracks of said track band, and wherein said positioning control process determines a revised data value for at least one of said position algorithm initialization data values for replacement of the respective one of said predetermined plurality of position algorithm initialization data values in said memory.

9. The disk drive of claim 6 or B wherein performance of said positioning control process provides for maintaining the position of said transducer with respect to a predetermined track by the application of a position control signal to said actuator where said position control signal (0) is determined as

10. The disk drive of claim 9 wherein said postioning control process utilizes said predetermined initialization data value in determining a position seek control control signal, for application to said actuator, as

11. A disk drive system comprising:

(a) a disk assembly including a disk for storing data in a plurality of concentric tracks, each track including a plurality of sectors, said plurality of concentric tracks being located within a track band on a surface of said disk a transducer for reading data from the disk, a spin motor for rotating the disk in response to a commutation control signal, an actuator for positioning the transducer relative to the disk in response to a position control signal; and

(b) control means for controlling said disk assembly, said control means including a microcontroller, a memory providing for the storage of a control program and initialization data values, said memory being coupled to said microcontroller to allow said microcontroller to execute said control program dependant on said initialization data values, the execution of said control program providing for the performance of a plurality of control processes with respect to each sector as it passes said transducer, said plurality of control processes including a positioning process providing for the generation and provision of said positioning signal to said actuator by said microcontroller, said positioning process determining said position control signal based on a predetermined initialization data value stored in said memory with respect to a predetermined track, said positioning process including a subprocess for determining a revised initialization data value and for storing said revised initialization data value in said memory with respect to said predetermined track.

12. In a disk drive including a media providing for the storage of data, a spin motor for rotating said media, an actuator for positioning a sensor with respect to a surface of said disk for the transfer of data, a memory for storing a control program and initialization data, a microcontroller dedicated to the control of said disk drive through the execution of said control program and a host computer interface for the transfer of host computer commands and data, an improvement in the control function performed by said microcontroller upon execution of the control program, wherein the improvement comprises:

means for communicating diagnostic commands and data with said microcontroller independent of said host computer interface; and

a control program providing for the performance of a plurality of control functions with respect to said disk drive in response to the execution of corresponding control processes of said control program, the execution of a first predetermined set of said control processes being responsive to control messages determined by a second predetermined set of control processes, said second predetermined set of control processes including a host interface control process and monitor control process, said host interface control process providing for the issuing of control messages to said first predetermined set of control processes in response to host computer commands and said monitor control process providing for the issuing of control messages to said first predetermined set of control processes in response to diagnostic commands and received from said communicating means.

13. The disk drive of claim 12 wherein said improvement further comprises:

(a) first means, coupled between said microcontroller and said spin motor, for transferring a spin control signal from said microcontroller to said spin motor and returning a spin sense signal corresponding to the response of said spin motor to said spin control signal; and

(b) second means, coupled between said microcontroller and said actuator, for transferring a position control signal from said microcontroller to said actuator and returning a position sense signal corresponding to the position of said sensor with respect to a predetermined track and a sector timing signal corresponding to the position of said sensor with respect to a predetermined sector of said predetermined track;

said first predetermined set of control processes including a sector control process, a spin control process and an actuator control process, execution of said sector control process providing for the repeated execution of said sector spin and actuator control processes with respect to the sensors as they rotate past said sensor, execution of said spin control process providing for control of the rotation rate of said disk, in response to said spin sense signal and said sector timing signal, by generation of said spin control signal, and execution of said actuator control process providing for control of the position of said sensor with respect to said predetermined track, in response to said position sense signal, by generation of said position control signal, said monitor control process providing for the communication of data corresponding to the performance of said first predetermined set of control processes in response to diagnostic compounds.

14. The disk drive of claim 13 wherein said monitor control process further provides for the modification of said initialization data stored by said memory, whereby the performance of said first predetermined set of control processes is modified dependant on the physical characteristics of said disk drive.