Table 154: Write Dma (Cah/Cbh) - Hitachi HDT725025VLA380 - Deskstar 0A33423 T7K500 250GB SATA 7200RPM 8MB Cache Hard Drive Specifications

12.46 Write DMA (CAh/CBh)
Table 155: Write DMA (CAh/CBh)
Command Block Output Registers
Register
Data
Feature
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Command
Error Register
7 6 5
CRC UNC 0 IDN
V 0 0
The Write DMA command transfers one or more sectors of data from the host to the device and then the data is
written to the disk media.
The sectors of data are transferred through the Data Register16 bits at a time.
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 available.
If an uncorrectable error occurs, the write will be terminated at the failing sector.
Output parameters to the device
Sector Count
Sector Number
Cylinder High/Low This indicates number of the first sector to be transferred. (L = 0) In LBA mode this reg-
H
R
Input parameters from the device
Sector Count
7 6 5 4 3 2 1 0
- - - - - - - -
- - - - - - - -
V V V V V V V V
V V V V V V V V
V V V V V V V V
V V V V V V V V
1 L 1 D H H H H
1 1 0 0 1 0 1 R
4 3 2 1
0 ABT T0N AMN
V 0 V 0
This indicates the number of continuous sectors to be transferred. If zero is specified, then
256 sectors will be transferred.
This indicates the sector number of the first sector to be transferred. (L = 0)In LBA mode
this register contains the LBA bits 0–7. (L = 1)
ister contains the LBA bits 8–15 (Low) and bits 16–23 (High). (L= 1)
This indicates the head number of the first sector to be transferred. (L = 0) In LBA mode
this register contains the LBA bits 24–27. (L = 1)
This indicates the retry bit. This bit is ignored.
This indicates the number of requested sectors not transferred. The Sector Count will be
zero unless an unrecoverable error occurs.
Deskstar T7K500 Hard Disk Drive Specification
Command Block Input Registers
Register
Data
Error
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Status
0 7 6 5
BSY RDY DF DSC DRQ
0 0 V 0
245
7 6 5 4 3 2 1 0
- - - - - - - -
see below
V V V V V V V V
V V V V V V V V
V V V V V V V V
V V V V V V V V
- - - - H H H H
see below
Status Register
4 3 2 1
COR IDX
V - 0 -
0
ERR
V