Table 86.Read Dma Ext Command (25H); Read Multiple Ext (29H) - Hitachi 7K250 - Deskstar - Hard Drive Specifications

12.21 Read Multiple Ext (29h)

Table 87: Read DMA Ext Command (25h)
Command Block Output Registers
Register
Data Low
Data High
Current
Feature
Previous
Current
Sector
Count
Previous
Current
Sector
Number
Previous
Current
Cylinder
Low
Previous
Cylinder Current
Previous
High
Device/Head
Command
7 6 5
CRC UNC 0
0 V 0
The Read Multiple Ext command reads one or more sectors of data from disk media, then transfers the data from
the device to the host.
The sectors are transferred through the Data Register 16 bits at a time. Command execution is identical to the Read
Sector(s) command except that an interrupt is generated for each block (as defined by the Set Multiple command)
instead of for each sector.
Output parameters to the device
Sector Count Current
Sector Count Previous
Sector Number Current
Sector Number Previous
Cylinder Low Current
Cylinder Low Previous
Cylinder High Current
Cylinder High Previous
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
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 - D - - - -
0 0 1 0 1 0 0 1
Error Register
4 3 2 1
IDN 0 ABT T0N AMN
V 0 V 0
The number of continuous sectors to be transferred low order, bits (7:0).
The number of continuous sectors to be transferred high order, bits (15:8). If
0000h in the Sector Count register is specified, 65,536 sectors will be transferred.
LBA (7:0)
LBA (31:24)
LBA (15:8)
LBA (39:32)
LBA (23:16)
LBA (47:40)
Deskstar 7K250 Hard Disk Drive Specification
Command Block Input Registers
Register
Data Low
Data High
Error
Sector
Count
Sector
Number
Cylinder
Low
Cylinder
High
Device/Head
Status
0 7 6
BSY RDY DF DSC DRQ
V 0 V
150
7 6 5 4 3 2 1 0
- - - - - - - -
- - - - - - - -
see below
HOB=0 - - - - - - - -
HOB=1 - - - - - - - -
HOB=0 V V V V V V V V
HOB=1 V V V V V V V V
HOB=0 V V V V V V V V
HOB=1 V V V V V V V V
HOB=0 V V V V V V V V
HOB=1 V V V V V V V V
- - - - - - - -
See below ...
Status Register
5 4 3 2
COR IDX
0 V - 0
1 0
ERR
- V