FUJITSU MHW2120BS - Manual (Page 115)

5.3 Host Commands
At command completion (Shadow Block Registers contents to be read)
ST Status information
DH x L x x HD No. / LBA
CH
CL
SN
SC
ER
Start cylinder No. [MSB] / LBA
Start cylinder No. [LSB] / LBA
Start sector No. / LBA [LSB]
00 (*1)
Error information
*1 If the command is terminated due to an error, the remaining
number of sectors of which data was not transferred is set in this
register.
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