
208 The Essential Guide to Serial ATA and SATA Express
Status Field
Bit Description
7 Device Busy (BSY)
The Busy bit is transport dependent. In legacy devices, this bit informed the host that it was busy.
6 Device Ready (DRDY)
The Data Ready bit is transport dependent.
(a) Refer to the appropriate transport standard for the usage of the Data Ready bit.
(b) In ATA/ATAPI-7, this bit was documented as the DRDY bit.
(c) It was used by a device when it was ready to send read data.
5 Device Fault/Stream Error (SE or DF)
The Stream Error bit shall be set to one if an error occurred during the processing of a command in the
Streaming feature set, ...