K6610170
Rev.2
Dec 22, 2004
- 122 -
7.5.55. Write Buffer [E8h]
Task
File
Registers
7 6 5 4 3 2 1 0
Command E8h
LBA High
XX
LBA Mid
XX
LBA Low
XX
Device/Head
X X X
DRV
X X X X
Sector Count
XX
Features
XX
The WRITE BUFFER command allows the host to write 512 bytes of data to the sector buffer of the device.
When the WRITE BUFFER command and the READ BUFFER command are issued consecutively, the
same data is read.
7.5.56. Write DMA [CAh, CBh]
Task
File
Registers
7 6 5 4 3 2 1 0
Command CAh
or
CBh
LBA High
L = 0: Cylinder number bit 15 - 8
L = 1: 28-bit LBA address bit 23 - 16
LBA Mid
L = 0: Cylinder number bit 7 - 0
L = 1: 28-bit LBA address bit 15 - 8
LBA Low
L = 0: Sector number
L = 1: 28-bit LBA address bit 7 - 0
Device/Head
X
L
X
DRV L = 0: Head Number
L = 1:28-bit LBA
address bit 27-24
Sector Count
Sector count
Features
XX
This command executes in a similar manner to the WRITE SECTORS command except for the followings:
-
The host initializes a slave-DMA channel prior to issuing the command.
-
Data transfers are qualified by DMARQ and are performed by the slave-DMA channel.
-
The device issues only one interrupt per command to indicate that data transfer has terminated and
status is valid.
If an error occurs, the write terminates at the sector where the error occurred. The command Block
Registers contain the cylinder, head, and sector numbers or 28-bit LBA address where the error occurred.