IBM DTLA-305040 - Deskstar 41.1 GB Hard Drive, Specifications

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12.12 Read DMA (C8h/C9h)
see below Status 1 1 0 0 1 0 0 R Command
- - - - H H H H Device/Head 1 L 1 D H H H H Device/Head
V V V V V V V V
Cylinder High
V V V V V V V V
Cylinder High
V V V V V V V V Cylinder Low V V V V V V V V Cylinder Low
V V V V V V V V Sector Number V V V V V V V V Sector Number
V V V V V V V V
Sector Count
V V V V V V V V
Sector Count
see below
Error
- - - - - - - -
Feature
- - - - - - - - Data - - - - - - - - Data
7 6 5 4 3 2 1 0
Register
7 6 5 4 3 2 1 0
Register
Command Block Input
Registers
Command Block Output
Registers
V – 0 – V 0 V 0 V 0 V 0 V 0 V V
ERR IDX COR DRQ DSC DF RDY BSY AMN T0N ABT 0 IDN 0 UNC CRC
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
Status Register Error Register
Figure 98. Read DMA Command (C8h/C9h)
The Read DMA 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.
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 com-
mand 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.
Output parameters to the device
Sector Count The number of continuous sectors to be transferred. If zero is specified, then 256
sectors will be transferred.
Sector Number The sector number of the first sector to be transferred. (L=0)
In LBA mode, this register specifies LBA address bits 0 - 7 to be transferred.
(L=1)
Deskstar 40GV & 75GXP hard disk drive specifications
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