Seagate Medalist ST31082A, Product Manual

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Chapter 6 Register Addresses and Functions
Page 40 ST3636A/ST31082A/ST31276A
• DWF is the drive write fault bit. When there is an error, this bit is not
changed until the Status register is read by the host, at which time the bit
again indicates the current write fault status.
• DSC is the drive seek complete bit. It is an indication that the actuator is
on track. When there is an error, this bit is not changed until the Status
register is read by the host, at which time the bit again indicates the
current readiness of the drive. This bit will be reset at power-up and will
remain reset until the drive is up to speed and ready to accept a command.
• DRQ is the data request bit, which indicates that the drive is ready for
transfer of a word or a byte of data between the host and the Data register.
• CORR is the corrected data bit, which is not used in this drive.
• IDX is the index bit which is set once per disk revolution. This function is
not updated by this drive.
• ERR is the error bit, which indicates that the previous command ended in
some type of error. The other bits in the Status register, as well as the bits
in the Error register, will have additional information as to the cause of the
error.
Alternate Status Register
Port Address: 3F6
Chip Select:
-HOST CS1
Register Address: 6
Function: Read only
Description: This register contains the same information as the Status
register in the Task File. The only difference is that reading this register does
not imply interrupt acknowledge to reset a pending interrupt.
The bits in this register are defined below:
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
BSY DRDY DWF DSC DRQ CORR IDX ERR
See the description of the Status register for definitions of the bits in this
register.