Datasheet

Travelstar 80GN Hard Disk Drive Specification

130

13.16 Read Multiple (C4h)

Table 87: 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. If zero is specified, 256

sectors will be transferred.

LBA Low This indicates the sector number of the first sector to be transferred. (L = 0)

In LBA mode, this register contains LBA bits 0–7. (L = 1)

LBA High/Low This indicates the cylinder number of the first sector to be transferred. (L = 0)

In LBA mode, this register contains LBA bits 8–15 (Mid), 16–23 (High). (L = 1)

H This indicates 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 This indicates the number of requested sectors not transferred. This number is zero unless

an unrecoverable error occurs.

LBA Low This indicates the sector number of the last 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

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

LBA Low V V V V V V V V LBA Low V V V V V V V V

LBA Mid V V V V V V V V LBA Mid V V V V V V V V

LBA High V V V V V V V V LBA High V V V V V V V V

Device 1 L 1 D H H H H Device - - - - - 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 V 0V0V- 0- V