Disk drive employing read channel IC with common port for data and servo

• US 6,278,568 B1
• Filed: 12/30/1998
• Issued: 08/21/2001
• Est. Priority Date: 03/11/1997
• Status: Expired due to Term

• Current Assignee: Western Digital Corporation
• Original Assignee: Western Digital Corporation
• Inventors: Rakshani, Vafa James, Hull, Richard W., Cloke, Robert L., Turner, David P.
• Primary Examiner(s): Neal, Regina Y.
• Application Number:
  US09/223,475
• Time in Patent Office: 965 Days
• Field of Search: 360/46, 360/51, 360/65, 360/77.08
• US Class Current: 360/51
• CPC Class Codes: G11B 20/10009 Improvement or modification of read or write signals
• CPC Class Codes: G11B 20/10037 A/D conversion, D/A conversion, sampling, slicing and digital quantisation or adjusting parameters thereof
• CPC Class Codes: G11B 20/10055 using partial response filtering when writing the signal to the medium or reading it therefrom
• CPC Class Codes: G11B 20/1217 on discs
• CPC Class Codes: G11B 20/1258 where blocks are arranged within multiple radial zones, e.g. Zone Bit Recording or Constant Density Recording discs, MCAV discs, MCLV discs
• CPC Class Codes: G11B 20/1403 characterised by the use of two levels
• CPC Class Codes: G11B 2020/10888 the kind of data being the selection criterion
• CPC Class Codes: G11B 2020/1232 sector, i.e. the minimal addressable physical data unit
• CPC Class Codes: G11B 2020/1267 Address data
• CPC Class Codes: G11B 2020/1275 Calibration data, e.g. specific training patterns for adjusting equalizer settings or other recording or playback parameters
• CPC Class Codes: G11B 2020/1282 in embedded servo fields
• CPC Class Codes: G11B 2020/1287 Synchronisation pattern, e.g. VCO fields specific bit sequences of sync patterns G11B20/1403; A/V synchronisation G11B27/00
• CPC Class Codes: G11B 2020/1292 Enhancement of the total storage capacity
• CPC Class Codes: G11B 2220/20 Disc-shaped record carriers
• CPC Class Codes: G11B 2220/2516 Hard disks
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: G11B 5/5965 Embedded servo format G11B5/59655 takes precedence

Abstract

A disk drive includes a disk having a disk surface. The disk surface has a plurality of tracks arranged in an embedded servo format including servo track segments for storing servo data and data track segments for storing user data. Data from the disk surface is read to produce a time-multiplexed analog read signal that during a revolution of the disk represents analog read servo data during each of a first set of time intervals and represents analog read user data during each of a second set of time intervals. The disk drive further includes a controller and a channel integrated circuit chip. The controller includes a controller port. The channel integrated circuit chip includes an input for receiving the time-multiplexed analog read signal. The time-multiplexed analog read signal is processed to generate data symbols representing recovered servo data and recovered user data. The channel integrated circuit chip includes a channel port for transferring both the recovered servo data and the recovered user data. The disk drive further includes a communication bus connected between the channel port and the controller port. The channel port transfers both the recovered servo data and the recovered user data to the communication bus. The communication bus transfers both the recovered servo data and the recovered user data to the controller port.

Claims

1. A disk drive comprising:

a disk having a disk surface, the disk surface having a plurality of tracks arranged in an embedded servo format including servo track segments for storing servo data and data track segments for storing user data;

read means for reading the servo data and the user data from the disk surface, the read means being operative during a user-data read operation to produce a time-multiplexed analog read signal that during a revolution of the disk represents analog read servo data during each of a first set of time intervals and represents analog read user data during each of a second set of time intervals;

a controller including a controller port;

a channel integrated circuit chip including;

a. an input for receiving the time-multiplexed analog read signal;

b. signal processing means for processing the time-multiplexed analog read signal to generate data symbols representing recovered servo data and recovered user data; and

c. a channel port;

a communication bus connected between the channel port and the controller port;

the channel port transferring both the recovered servo data and the recovered user data to the communication bus;

the communication bus transferring both the recovered servo data and the recovered user data to the controller port.

2. The disk drive of claim 1 wherein the channel port is a parallel port.

3. The disk drive of claim 2 wherein the parallel port is eight (8) bits wide.

4. The disk drive of claim 1 further comprising:

a microprocessor;

a microprocessor bus coupled to the microprocessor; and

the channel integrated circuit chip including a microprocessor port coupled to the microprocessor bus.

5. The disk drive of claim 4 wherein the microprocessor port is a parallel port.

6. The disk drive of claim 4 wherein the channel integrated circuit chip includes a plurality of microprocessor-addressable registers.

7. The disk drive of claim 6 wherein:

the data track segments include a plurality of servo bursts for fine track positioning;

the time-multiplexed analog read signal represents analog read servo bursts during a third set of time intervals;

the channel integrated circuit chip includes;

means for demodulating the analog read servo bursts for producing servo burst information; and

means for storing the servo burst information in one of the microprocessor-addressable registers.

8. The disk drive of claim 1 wherein the channel port includes means for producing a clock signal for timing the data symbols, the disk drive further comprising:

means for transferring the clock signal to the controller.

9. The disk drive of claim 8 wherein the clock signal is a byte clock signal.

10. A disk drive comprising:

a disk having a disk surface, the disk surface having a plurality of tracks arranged in an embedded servo format including servo track segments for storing servo data and data track segments for storing user data;

read means for reading the servo data and the user data from the disk surface, the read means being operative during a user-data read operation to produce a time-multiplexed analog read signal that during a revolution of the disk represents analog read servo data during each of a first set of time intervals and represents analog read user data during each of a second set of time intervals;

a controller including a controller port;

control means for providing a channel parameter select signal;

a channel integrated circuit chip including;

a. an input for receiving the time-multiplexed analog read signal;

b. storage means for storing a servo data channel parameter and a user data channel parameter;

c. switching means responsive to the channel parameter select signal for producing a selected channel parameter signal by selecting the servo data channel parameter during the first set of time intervals and the user data channel parameter during the second set of time intervals;

d. sampled signal processing means responsive to the time-multiplexed analog read signal and the selected channel parameter signal for generating data symbols representing recovered servo data and the recovered user data; and

e. a channel port;

a communication bus connected between the channel port and the controller port;

the channel port transferring both the recovered servo data and the recovered user data to the communication bus;

the communication bus transferring both the recovered servo data and the recovered user data to the controller port.