It seems Allen Pulsifer wrote:
> According to the DPTA-3xxxxx spec from IBM, if the drive has fully entered
> Standby mode, it can take up to 31 seconds for it to spin back up.
> (See sections 3.3.6.1 and 13.0). Other drive models may take even
> longer, and even after the drive is back up, it may take a few seconds
> to respond to the command.
>
> You might have to set the timeout value as high as 45-60 seconds in
> order to get reliable operation.
>
> One possibility: the Check Power Mode command (sections 10.5.2 and 12.1)
> allows you to determine if the drive is in Standby mode. You might
> be able to timeout after 5-10 seconds, abort the read/write command,
> do a Check Power Mode command, and if the drive is in the process
> of spinning back up, then wait patiently for it to come to life
> before retrying the original read/write command.
>
> It looks to me like you would have to do a soft reset (sections 11.0,
> 9.6 and 10.1) in order to abort the read/write command. A soft
> reset would also cause the drive to come back to life if it were
> in Sleep mode (sections 3.3.6, 10.5.1 and 12.31).
>
> Note that section 13.0 (page 190) is explicit about this procedure:
> "We recommend that the host system executes Soft reset and then
> retry to issue the command if the host system would occur timeout
> for the device."
This is more or less what is done now, I just doesn't do the
check power mode after the reset, there is not much point, I
know the disk is coming up.
-Søren
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