Hitachi ULTRASTAR 15K450 HUS154530VLF400 - Manual (Page 237)

Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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19.20.6 Enable Expander Communications Protocol and Echo Buffer (Mode11010b)
Receipt of a READ BUFFER command with this mode (11010b) causes a communicative expander to enter the expanded
communication protocol mode. SCSI target devices that receive a READ BUFFER command with this mode shall process it
as if it were a READ BUFFER command with mode 01010b (Read Data from Echo Buffer (Mode 01010b)*, page 219.