System and method for detecting and recovering from an off-format state in an optical disc drive

Abstract

A disc drive includes a tracking actuator, and determines when the tracking actuator is positioned off a formatted portion of optical media in the disc drive. The optical media includes a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. Tracking control effort is monitored to determine when the tracking actuator is in the off-format condition and whether tracking good or tracking bad is detected within a predetermined time period. An absolute value of the tracking control effort is generated and the absolute value of the tracking control effort is filtered. An off-format condition is indicated if the filtered value of the tracking control effort is not within a predetermined threshold value.

1 . An optical disc drive, comprising: 
 a tracking actuator; and    instructions operable to determine when the tracking actuator is positioned off a formatted portion of optical media in the disc drive.    
   
   
       2 . The system, as set forth in  claim 1 , further comprising: 
 instructions operable to monitor tracking control effort to determine when the tracking actuator is in the off-format condition.    
   
   
       3 . The system, as set forth in  claim 1 , wherein the instructions operable to determine when the tracking actuator is positioned off a formatted portion of optical media in the disc drive are further operable to determine whether tracking good or tracking bad is detected within a predetermined time period.  
   
   
       4 . The system, as set forth in  claim 2 , further comprising: 
 instructions operable to generate an absolute value of the tracking control effort.    
   
   
       5 . The system, as set forth in  claim 4 , further comprising: 
 instructions operable to filter the absolute value of the tracking control effort.    
   
   
       6 . The system, as set forth in  claim 5 , further comprising: 
 a low pass filter to filter the absolute value of the tracking control effort.    
   
   
       7 . The system, as set forth in  claim 6 , further comprising: 
 instructions operable to determine whether the absolute, filtered value of the tracking control effort is within a predetermined threshold value.    
   
   
       8 . The system, as set forth in  claim 1 , further comprising: 
 instructions operable to indicate an off-format condition when the tracking control effort is not within the predetermined threshold value.    
   
   
       9 . A method for controlling an optical disc drive, wherein the optical disc drive includes a tracking actuator, the method comprising: 
 determining when the tracking actuator is positioned off a formatted portion of optical media in the disc drive.    
   
   
       10 . The method, as set forth in  claim 9 , further comprising: 
 monitoring tracking control effort to determine when the tracking actuator is in the off-format condition.    
   
   
       11 . The method, as set forth in  claim 9 , wherein determining when the tracking actuator is positioned off a formatted portion of optical media in the disc drive includes determining whether tracking good or tracking bad is detected within a predetermined time period.  
   
   
       12 . The method, as set forth in  claim 11 , further comprising: 
 generating an absolute value of the tracking control effort.    
   
   
       13 . The method, as set forth in  claim 12 , further comprising: 
 filtering the absolute value of the tracking control effort.    
   
   
       14 . The method, as set forth in  claim 13 , further comprising: 
 low pass filtering the absolute value of the tracking control effort.    
   
   
       15 . The method, as set forth in  claim 14 , further comprising: 
 determining whether the absolute, filtered value of the tracking control effort is within a predetermined threshold value.    
   
   
       16 . The method, as set forth in  claim 9 , further comprising: 
 indicating an off-format condition when the tracking control effort is not within the predetermined threshold value.    
   
   
       17 . A computer program product, comprising: 
 instructions for implementing the method of  claim 9 .    
   
   
       18 . A data signal comprising: 
 instructions for implementing the method of  claim 9 .    
   
   
       19 . An apparatus for controlling an optical disc drive, wherein the optical disc drive includes a tracking actuator, the apparatus comprising: 
 means for determining when the tracking actuator is positioned off a formatted portion of optical media in the disc drive.    
   
   
       20 . The apparatus, as set forth in  claim 19 , further comprising: 
 means for monitoring tracking control effort to determine when the tracking actuator is in the off-format condition.    
   
   
       21 . The apparatus, as set forth in  claim 19 , wherein the means for determining when the tracking actuator is positioned off a formatted portion of optical media in the disc drive includes means for determining whether tracking good or tracking bad is detected within a predetermined time period.  
   
   
       22 . The apparatus, as set forth in  claim 21 , further comprising: 
 means for generating an absolute value of the tracking control effort.    
   
   
       23 . The apparatus, as set forth in  claim 22 , further comprising: 
 means for filtering the absolute value of the tracking control effort.    
   
   
       24 . The apparatus, as set forth in  claim 23 , further comprising: 
 means for low pass filtering the absolute value of the tracking control effort.    
   
   
       25 . The apparatus, as set forth in  claim 24 , further comprising: 
 means for determining whether the absolute, filtered value of the tracking control effort is within a predetermined threshold value.    
   
   
       26 . The apparatus, as set forth in  claim 19 , further comprising: 
 means for indicating an off-format condition when the tracking control effort is not within the predetermined threshold value.    
   
   
       27 . The apparatus, as set forth in  claim 19 , wherein the optical media includes a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten.