SST58LD024 datasheet(26/40 Pages) SST

26 / 40 page

Data Sheet

ATA-Disk Chip

SST58SD008 / 016 / 024 / 032 / 048 / 064 / 096 / 128 / 192

SST58LD008 / 016 / 024 / 032 / 048 / 064 / 096 / 128 / 192

S71167-05-000

9/01

391

3.2.1.9 Read Multiple - C4H

The Read Multiple command is similar to the Read Sector(s) command. Interrupts are not generated on

every sector, but on the transfer of a block which contains the number of sectors defined by a Set

Multiple command.

Command execution is identical to the Read Sectors operation except that the number of sectors

defined by a Set Multiple command are transferred without intervening interrupts. DRQ qualification of

the transfer is required only at the start of the data block, not on each sector.

The block count of sectors to be transferred without intervening interrupts is programmed by the Set

Multiple Mode command, which must be executed prior to the Read Multiple command. When the Read

Multiple command is issued, the Sector Count Register contains the number of sectors (not the number

of blocks or the block count) requested. If the number of requested sectors is not evenly divisible by the

block count, as many full blocks as possible are transferred, followed by a final, partial block transfer.

The partial block transfer is for n sectors, where

n = remainder (sector count/block count).

If the Read Multiple command is attempted before the Set Multiple Mode command has been executed

or when Read Multiple commands are disabled, the Read Multiple operation is rejected with an Aborted

Command error. Disk errors encountered during Read Multiple commands are posted at the beginning

of the block or partial block transfer, but DRQ is still set and the data transfer will take place as it

normally would, including transfer of corrupted data, if any.

Interrupts are generated when DRQ is set at the beginning of each block or partial block. The error

reporting is the same as that on a Read Sector(s) Command. This command reads from 1 to 256

sectors as specified in the Sector Count register. A sector count of 0 requests 256 sectors. The transfer

begins at the sector specified in the Sector Number Register.

At command completion, the Command Block Registers contain the cylinder, head and sector number

of the last sector read.

If an error occurs, the read terminates at the sector where the error occurred. The Command Block

Registers contain the cylinder, head and sector number of the sector where the error occurred. The

flawed data is pending in the sector buffer.

Subsequent blocks or partial blocks are transferred only if the error was a correctable data error. All

other errors cause the command to stop after transfer of the block which contained the error.

Bit ->

Command (7)

C4H

C/D/H (6)

LBA

Drive

Head (LBA 27-24)

Cyl High (5)

Cylinder High (LBA 23-16)

Cyl Low (4)

Cylinder Low (LBA 15-8)

Sec Num (3)

Sector Number (LBA 7-0)

Sec Cnt (2)

Sector Count

Feature (1)

SST58LD024 Datasheet(PDF) 26 Page - Silicon Storage Technology, Inc

SST58LD024 Datasheet(HTML) 26 Page - Silicon Storage Technology, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Datasheet Download

Link URL