HANBit
HFDOM40KVxxx
recommended.
Write Multiple Command – C5h
Bit->
7
6
5
4
3
2
1
0
Command(7)
C/D/H(6)
C5h
X
LBA
X
Drive
Head
Cyl High(5)
Cyl Low(4)
Sec Num(3)
Sec Cnt(2)
Feature(1)
Cylinder High
Cylinder Low
Sector Number
Sector Count
X
Write Multiple Command
Note: The current revision of the CompactFlash Storage Card only supports a block count of 1 as indicated in the
Identify Drive Command information. This command is provided for compatibility with future products which may
support a larger block count.
This command is similar to the Write Sectors command. The CompactFlash Storage Card sets BSY within 400
nsec of accepting the command. Interrupts are not presented on each sector but on the transfer of a block which
contains the number of sectors defined by Set Multiple.
Command execution is identical to the Write Sectors operation except that the number of sectors defined by the
Set Multiple command is 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 the Set Multiple Mode command,
which must be executed prior to the Write 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) requested. If the number of requested
sectors is not evenly divisible by the sector/block, as many full blocks as possible are transferred, followed by a
final, 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
Mode command has been executed or when Write Multiple commands are disabled, the Write Multiple operation
will be rejected with an aborted command error.
Errors encountered during Write Multiple commands are posted after the attempted writes of the block or partial
block transferred. The Write command ends with the sector in error, even if it is in the middle of a block.
Subsequent blocks are not transferred in the event of an error. Interrupts are generated when DRQ is set at the
beginning of each block or partial block.
The Command Block Registers contain the cylinder, head and sector number of the sector where the error
occurred and the Sector Count Register contains the residual number of sectors that need to be transferred for
successful completion of the command, e.g., each block has 4 sectors, a request for 8 sectors is issued and an
error occurs on the third sector. The Sector Count Register contains 6 and the address is that of the third sector.
Write Multiple without Erase – CDh
Bit->
7
6
5
4
3
2
1
0
Command(7)
C/D/H(6)
CDh
X
LBA
X
Drive
Head
Cyl High(5)
Cyl Low(4)
Sec Num(3)
Sec Cnt(2)
Feature(1)
Cylinder High
Cylinder Low
Sector Number
Sector Count
X
Write Multiple without Erase
This command is similar to the Write Multiple command with the exception that an implied erase before write
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HANBit Electronics Co., Ltd.
Rev. 1.1 (December, 2003)
HANBIT [ HANBIT ELECTRONICS CO.,LTD ]
