Samsung 100737108-A

Spinpoint M8-DVR OEM Product Manual REV 1.0

8.2.40 Write Long (32h)

This command is obsolete in the ATA7 specification. The supporting of this command is for backwa rd

compatibility purpose. The use of this command is beyond the ATA standard and not recommended by the

manufacturer.

This command is similar to the Write Sec tors command, except that it writes the data and the ECC b ytes

directly fro m the sector buffer; the drive does not generate the ECC bytes itself. Only single sector Write

Long operations are supported. The transfer of the ECC bytes shall be 8 bits wide and 4 or device native

ECC bytes length.

8.2.41 Write Multiple Command (C5h, 39h: extended)

This command is similar to the Write Sectors command. Interrupts are not presented on each sector but on

the transfer of a block which contains the number of sectors defined by Set Multipl e.

Command execution is identical to the Write Sectors operation, except that the numbers of sectors defined b y

the Set Multiple command are transferred without intervening interrupts. DRQ qualification of the transfer is

required only at the start of the data block, not on each sector.

The block count of sectors to be transferred without intervening interrupts is programmed by th e Set Multiple

Mode command, which shall be executed prior to the Read Multiple command.

When the Write Multiple command is issued, the Sector Count register contains the number of sectors (not

the number of blocks or the block count) requ ested.

If the number of requested sectors is not evenly divisible by the block count, as many full blocks as possible

are transferred, followed by a f inal, partial block transfer. The partial block transfer is for n sectors, where

n = Remainder (Sector Count / Block Count)

If the Write Multiple command is attempted before the Set Multiple Mo de command has been executed, or

when Write Multiple commands are disabled, the Write Multiple operation is rejected with an aborted

command error.

Disk errors encountered during execution of Writ e Multiple commands are posted after the attempted disk

write of the block. Interrupts are generated when DRQ is set at the beginning of each block or partial block.

The contents of the Command Block registers, f ollowing the transfer of a data block which had a sector in

error, are undefined. The host should retry the transfer as individual requests to obtain valid error information.

This command writes from 1 to 256 sectors, as specified in the Sector Count register (a sector count of zero

requests 256 sectors), beginning at the specified sector. Refer to Sectio n 6.7 for the DRQ, IRQ and BSY

protocol on data transfers.

If the drive is not already on th e desired track, an implied seek is performed. Once at the desired track, the

drive searches for the appropriate ID field.