IBM DBCA-204860 - Travelstar 4.8 GB Hard Drive, Технические характеристики

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This register contains the device status. The contents of this register are updated whenever an error occurs
and at the completion of each command.
If the host reads this register when an interrupt is pending, it is considered to be the interrupt acknowledge.
Any pending interrupt is cleared whenever this register is read.
If B S Y = 1 , no other bits in the register are valid.
Bit Definitions
BSY Busy. B S Y = 1 whenever the device is accessing the registers. The host should not
read or write any registers when B S Y = 1 .
If the host reads any register when
B S Y = 1 , the contents of the Status Register will be returned.
DRDY (RDY) Device Ready. R D Y = 1 indicates that the device is capable of responding to a
command. R D Y will be set to 0 during power on until the device is ready to accept
a command.
DF Device Fault. D F = 1 indicates that the device has detected a write fault condition.
D F is set to 0 after the Status Register is read by the host.
DSC Device Seek Complete. D S C = 1 indicates that a seek has completed and the device
head is settled over a track. DSC is set to 0 by the device just before a seek begins.
When an error occurs, this bit is not changed until the Status Register is read by the
host, at which time the bit again indicates the current seek complete status.
When the device enters into or is in Standby mode or Sleep mode, this bit is set by
device in spite of not spinning up.
DRQ Data Request. D R Q = 1 indicates that the device is ready to transfer a word or byte
of data between the host and the device. The host should not write the Command
register when D R Q = 1 .
CORR (COR) Corrected Data. Always 0.
IDX Index. I D X = 1 once per revolution. Since I D X = 1 only for a very short time during
each revolution, the host may not see it set to 1 even if the host is reading the Status
Register continuously. Therefore the host should not attempt to use IDX for timing
purposes.
ERR Error. E R R = 1 indicates that an error occurred during execution of the previous
command. The Error Register should be read to determine the error type. The
device sets E R R = 0 when the next command is received from the host.
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O E M Specifications of DBCA-2xxxxx 2.5 inch H D D