Method of high speed searching for a desired tape portion in a digital audio tape recorder

• US 5,179,479 A
• Filed: 06/07/1990
• Issued: 01/12/1993
• Est. Priority Date: 06/10/1989
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Ahn, Hong-Cho
• Primary Examiner(s): Dixon, Joseph L.
• Assistant Examiner(s): Robertson, David L.
• Application Number:
  US07/534,257
• Time in Patent Office: 950 Days
• Field of Search: 360/72.1, 360/72.2, 360/72.3, 369/47, 369/50, 369/53, 369/54
• US Class Current: 360/72.1
• CPC Class Codes: G11B 15/005 Programmed access in sequence to indexed parts of tracks of operating tapes, by driving or guiding the tape access by driving of both record carrier and head G11B15/1816; see prov. also G11B15/602
• CPC Class Codes: G11B 15/1816 Programmed access in sequence to indexed parts of operating tapes cooperating with rotating heads see provisional also G11B15/005
• CPC Class Codes: G11B 15/48 Starting; Accelerating; Decelerating; Arrangements preventing malfunction during drive change
• CPC Class Codes: G11B 2220/65 wherein solid state memory is used for storing indexing information or metadata
• CPC Class Codes: G11B 2220/90 Tape-like record carriers
• CPC Class Codes: G11B 2220/913 Digital audio tape [DAT] format
• CPC Class Codes: G11B 27/107 of operating tapes
• CPC Class Codes: G11B 27/11 by using information not detectable on the record carrier
• CPC Class Codes: G11B 27/13 the information being derived from movement of the record carrier, e.g. using tachometer
• CPC Class Codes: G11B 27/328 on a tape [TTOC]

Abstract

A tape searching method in a digital audio tape recorder by means of TOC (table of contents) and operation frequency sensed from a reel motor. The method for tape searching includes a first stage for receiving a positional information and a specific search mode; a second stage for reading out the TOC information; a third stage for obtaining a mean value of an operational signal sensed from a take-up reel and another operational signal sensed from a supply reel so as to drive a reel motor with a high speed by counting time and position of the tape; a fourth stage for checking if amount of tape wound onto the reels is a value of desired position and conforming said third step if the tape amount is not the value of desired position; and a sixth stage for making a slow, precise search gradually so as to detect a start ID and terminating the procedure when the amount of tape wound onto the reels is a value of desired position.

Claims

1. A method of high speed searching a digital audio tape having a table of contents stored thereon, said digital audio tape being on a digital audio tape recorder having tape supply reel, tape take-up reel and a reel motor, said method comprising the steps of:

reading said table of contents information from said digital audio tape for storage in a memory;

inputting a desired search speed and a desired program number into a microcomputer of said digital audio tape recorder;

determining whether said memory contains said table of contents information which can be read;

reading said table of contents information from said memory, if said step of determining results in a positive determination, for input into said microcomputer;

calculating a present tape position of said digital audio tape from data provided by said tape supply reel and said tape take-up reel;

driving said reel motor at said desired search speed;

determining whether a predetermined portion of said digital audio tape has been reached in response to said desired program number and said present tape position;

returning to said calculating step if said predetermined position has not been reached;

driving said reel motor at a speed slower that said desired speed if said step of determining whether said memory contains said table of contents information which can be read determines that said table of contents information can not be read or if said step of determining whether a predetermined portion of said digital audio tape has been reached determines said predetermined portion has been reached; and

detecting program identification during said step of driving said reel motor at a slower speed, said program identification being representative of said desired program number input to said microcomputer.

2. The method as claimed in claim 1 wherein said step of driving said reel motor at a slower speed comprises:

reducing said driving speed of said reel motor, if said predetermined tape position has been reached, from said desired search speed to a speed 200 times a playback operating speed of said reel motor; and

gradually reducing said driving speed from said 200 times speed in predetermined steps until said program identification is detected.

3. The method as claimed in claim 2 wherein said step of driving said reel motor at a slower speed comprises:

driving said reel motor at a speed 200 times a playback operating speed of said reel motor if said table of contents information can not be read; and

gradually reducing said driving speed from said 200 times speed in predetermined steps until said program identification is detected.

4. The method as claimed in claim 3 wherein said step of driving said reel motor at a slower speed further comprises:

driving said reel motor at said speed 200 times a playback operating speed of said reel motor if said table of contents information can not be read; and

gradually reducing said driving speed from said 200 times speed in predetermined steps until said program identification is detected.