Datasheet

13.0 Command Protocol
The commands are grouped into different classes according to the protocols followed for command exe-
cution. The command classes with their associated protocols are defined in the following text.
For all commands, the host must first check if BSY=1, and should proceed no further unless and until
BSY=0. For all commands, the host must also wait for RDY=1 before proceeding.
A device must maintain either BSY=1 or DRQ=1 at all times until the command is completed. The INTRQ
signal is used by the device to signal most, but not all, times when the BSY bit is changed from 1 to 0
during command execution.
A command shall only be interrupted with a hardware or software reset. The result of writing to the
Command register while BSY=1 or DRQ=1 is unpredictable and may result in data corruption. A com-
mand should only be interrupted by a reset at times when the host thinks there may be a problem, such
as a device that is no longer responding.
Interrupts are cleared when the host reads the Status Register, issues a reset, or writes to the Command
Register.
Hard disk drive specification for DSCM-11000/-10512/-10340
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