197 | 0xC5 | Current Pending Sector Count | 
| Count of "unstable" sectors (waiting to be remapped, because of read errors). If an unstable sector is subsequently read successfully, this value is decreased and the sector is not remapped. Read errors on a sector will not remap the sector (since it might be readable later); instead, the drive firmware should remember that the sector needs to be remapped, and remap it the next time it's written.[28] However some drives will not immediately remap such sectors when written; instead the drive will first attempt to write to the problem sector and if the write operation is successful then the sector will be marked good. This is a serious shortcoming, for if such a drive contains marginal sectors that consistently fail only after some time has passed following a successful write operation, then the drive will never remap these problem sectors. |