Deskstar 7K500 and Deskstar E7K500 Hard Disk Drive Specification
155
12.19 Read Multiple (C4h)
Table 118: Read Multiple (C4h)
The Read Multiple 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 command execution is identical to the
Read Sectors command with one exception: an interrupt is generated for each block—as defined by the Set Multi-
ple command—instead of for each sector.
Output parameters to the device
Sector Count This indicates the number of continuous sectors to be transferred. The Sector Count must
be set to one.
Sector Number This indicates the sector number of the sector to be transferred. (L = 0)
In LBA mode, this register contains LBA bits 0–7. (L = 1)
Cylinder High/Low This indicates the cylinder number of the sector to be transferred. (L = 0)
In LBA mode, this register contains LBA bits 8–15 (Low), 16–23 (High). (L = 1)
H This indicates the head number of the 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 This indicates the number of requested sectors not transferred. This number is zero unless
an unrecoverable error occurs.
Sector Number This indicates the sector number of the transferred sector. (L = 0)
In LBA mode, this register contains current LBA bits 0–7. (L = 1)
Command Block Output Registers Command Block Input Registers
Register 7 6 5 4 3 2 1 0 Register 7 6 5 4 3 2 1 0
Data - - - - - - - - Data - - - - - - - -
Feature - - - - - - - - Error see below
Sector Count V V V V V V V V Sector Count 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
Cylinder Low V V V V V V V V Cylinder Low 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
Device/Head 1 L 1 D H H H H Device/Head - - - - H H H H
Command 1 1 0 0 0 1 0 0 Status see below
Error Register Status Register
7654321 0 76543 21 0
CRC UNC 0 IDN 0 ABT T0N AMN BSY RDY DF DSC DRQ COR IDX ERR
0V0V0V0 0 0V0V- 0- V
To Next Page
Loading...
