| 摘要 |
<p>A split field buffer table (500) provides a headerless formatted disk drive (400). The split field buffer table (500) includes information that represents the number of sectors between two sequential servo fields or wedges (S1-S4) and that represents that a sector is split and that represents the sector split byte count. It also includes information that represents the physical sector address of the first sector after the servo wedge (S1-S4). Also, a data protection scheme where CRC generated from that data is exclusive-ored with an LSA. After being stored, the CRC is regenerated for that data. The CRC encoded with the LSA is exclusive-ored with the LSA again to remove that LSA. The CRC bytes are compared to each other. If not equal, then it is known that either the wrong LSA data is being transferred, or that the data is corrupted. A transfer control table is used to manage sector defects or other transfer adjustments. Each entry of the table contains the affected PSA, a bit to signify whether the LSA should be incremented, an action, an interrupt/branch bit and, preferably, parity. The increment bit should be set for logically skipped sectors and reset for defective sectors. The interrupt/branch bit causes a preferred maskable interrupt and a branch flag typically when the last sector of a track has been read or written. The actions can be take no action, skip the sector or skip the following indicated sectors.</p> |
