Table of Contents
Advertisement
10.17 Read DMA Ext (25h)
Command Block Output Registers
Register
7
Data Low
-
Data High
-
Current
-
Feature
Previous
-
Current
V
Sector Count
Previous
V
Current
V
Sector
Number
Previous
V
Current
V
Cylinder Low
Previous
V
Current
V
Cylinder High
Previous
V
Device/Head
1
Command
0
Error Register
7
6
5
4
CRC
UNC
0
IDN
V
Vs
0
V
Table 110 Read DMA Ext Command (25h)
The Read DMA command reads one or more sectors of data from disk media, and then transfers the data from
the device to the host.
The sectors are transferred through the Data Register 16 bits at a time.
The host initializes a slave-DMA channel prior to issuing the command. The 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 read will be terminated at the failing sector.
HITACHI Deskstar & CinemaStar P7K500 Hard Disk Drive specification (Rev 1.1)
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
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
1
D
-
-
-
-
0
1
0
0
1
0
1
3
2
1
0
0
ABT
T0N
AMN
0
V
0
0
152
Command Block Input Registers
Register
7
Data Low
-
Data High
-
Error
HOB=0
-
Sector Count
HOB=1
-
HOB=0
V
Sector
Number
HOB=1
V
HOB=0
V
Cylinder Low
HOB=1
V
HOB=0
V
Cylinder High
HOB=1
V
Device/Head
-
Status
Status Register
7
6
5
4
BSY
RDY
DF
DSC DRQ COR
0
V
0
V
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
V
V
V
V
V
V
V
V
V
V
-
-
-
-
-
-
-
...See Below...
3
2
1
0
IDX
ERR
-
0
-
V
- Quick Links:
- Data Sheet
- Jumper Settings(Pata Model)
Hide quick links:
Advertisement
Table of Contents
