IBM IC25N040ATCS04 - Travelstar 40 GB Hard Drive, Specifications

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13.13 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 and then transfers the data
from the device to the host. It transfers the sectors 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
the DMARQ and are performed by the slave-DMA channel. The device issues only one interrupt per
command to indicate that the data transfer has terminated and that status is available.
If an uncorrectable error occurs, the read will be terminated at the failing sector.
Output parameters to the device
Sector Count This indicates the number of continuous sectors to be transferred. If zero is
specified, then 256 sectors will be transferred.
Sector Number This indicates the sector number of the first sector to be transferred. (L = 0).
In LBA mode, this register specifies that LBA address bits 0–7 are to be
transferred. (L = 1)
Cylinder High/Low This indicates the cylinder number of the first sector to be transferred. (L = 0)
In LBA mode, this register specifies LBA address bits 8–15 (Low) and
16–23 (High) to be transferred. (L = 1)
H This indicates the head number of the first sector to be transferred. (L = 0)
In LBA mode this register specifies the LBA bits 24–27 to be transferred. (L = 1)
R This indicates the retry bit , but this bit is ignored.
Travelstar 60GH & 40GN hard disk drive specifications
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