IBM IC35L020 - Deskstar 20 GB Hard Drive - Read Multiple (C4 H); Figure 93. Read Multiple Command (C4 H)

15.15 Read Multiple (C4h)
see below
Status
1 1 0 0 0 1 0 0
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–V0V0V0V0V0V0
ERRIDXCORDRQDSCDFRDYBSYAMNT0NABT0IDN0UNCCRC
0123456701234567
Status RegisterError Register
Figure 93. Read Multiple Command (C4h)
The Read Multiple 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 Sectors 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
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 contains LBA bits 0–7. (L=1)
Cylinder High/Low
The cylinder number of the first sector to be transferred. (L=0)
In LBA mode, this register contains LBA bits 8–15 (Low), 16–23 (High). (L=1)
H
The head number of the first sector to be transferred. (L=0)
In LBA mode this register contains LBA bits 24–27. (L=1)
Input parameters from the device
Sector Count
The number of requested sectors not transferred. This will be zero unless an
unrecoverable error occurs.
Deskstar 60 GXP Hard disk drive specification
130