The Write (10) command was introduced to cope with 32-bit LBAs. It also included four other enhancements. Disable Page Out (DPO) allows the initiator to warn the target that the data being written is unlikely to be read back soon and so is not worth keeping in the target's data cache. Force Unit Access (FUA) tells the target to immediately send the data to the media surface and to not buffer it through a cache. The EBP bit tells the target that it may skip the erase process when writing data. The RelAdr bit is used to indicate that the LBA value is relative (only used with linked commands). The CDB structure is:
| bit→ ↓byte |
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|
| 0 | Operation code = 2Ah | |||||||
| 1 | WRPROTECT | DPO | FUA | Reserved | FUA_NV | Obsolete | ||
| 2–5 | LBA | |||||||
| 6 | Reserved | Group Number | ||||||
| 7–8 | Transfer length | |||||||
| 9 | Control | |||||||
Read more about this topic: SCSI Write Commands
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