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OEM MANUAL:K6602924
The controller calculates the timing to be considered as Buffer Full / Empty in the
number of blocks based on the specified ratio, the transfer data size and the buffer
size.
Buffer Full Ratio specifies the amount of data considered as Buffer Full during the
READ operation, and the controller uses it as a timing of reconnection for data
transfer to the host computer.
The controller uses the value which is rounded down in the number of blocks based
on the ratio.
If Buffer Full Ratio is set to 0, the controller considers as Buffer Full when the first
block to be read is detected.
Further, the controller gives priority to the internal algorithm irrespective of the
value specified in the Buffer Full Ratio.
The Buffer Empty Ratio specifies the amount of written data considered as Buffer
Empty during the WRITE operation, and the controller uses it as a timing of
reconnection for data transfer from the host computer.
The controller uses the value which is rounded down in the number of blocks based
on the ratio.
If Buffer Empty Ratio is set to 0, the controller considers as Buffer Empty when
the first block to be written is detected.
The controller uses this parameter when the reconnection is attempted for data
transfer after the disconnection caused by Buffer Full, then this parameter is
effective when the amount of transfer data exceeds the buffer size. However,
when the data transfer from the host computer and the write operation to the disk
drive are overlapped, this parameter may not be used even if the amount of
transfer data exceeds the buffer size.
Further, the controller gives priority to the internal algorithm irrespective of the
value specified in the Buffer Empty Ratio.
Bus Inactivity Limit is specified by the host computer as the maximum time in 100
micro seconds increments which the controller is allowed to maintain the bus busy
without handshaking until it shall disconnect.
Bus Inactivity Limit of 0 shows that there is no limit in time.
The controller supports Bus Inactivity Limit = 0 only.
Disconnect Time Limit is specified by the host computer as the minimum time in
100 micro seconds increments which the controller continues disconnection until
reconnection is initiated.
Disconnect Time Limit of 0 shows that there is no limit in time.
This field needs to be always specified to 0 as the controller does not support this
field.
MODE SELECT:(15h)
5 COMMAND DESCRIPTIONS
Revision: 1 / Date: 2003.03.06
Page: 130 / 273
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