5.3 Host Commands

(38)READ DMA EXT (X '25')

•Description

This command is the extended command of the READ DMA command. The LBA specification is increased from 28 bits to 48 bits, and the maximum number of sectors that can be transferred by a single command is changed from 100h to 10000h. Other command controls are the same as those of the READ DMA command.

•Error reporting conditions

(1)The command was issued in CHS mode (ST = 51h, ER = 04h).

The other error reporting conditions are the same as those of the READ DAM command.

At command issuance (Shadow Block Registers setting contents)

CM

0

0

1

0

0

1

0

1

 

 

 

 

 

 

 

 

 

 

DH

1

L

1

 

x

 

 

xx

 

 

 

 

 

 

 

 

 

 

 

CH EXP

 

 

 

 

LBA (47-40)

 

 

 

CH

 

 

 

 

LBA (23-16)

 

 

 

CL EXP

 

 

 

 

LBA (39-32)

 

 

 

CL

 

 

 

 

LBA (15-8)

 

 

 

SN EXP

 

 

 

 

LBA (31-24)

 

 

 

SN

 

 

 

 

LBA (7-0)

 

 

 

SC EXP

 

 

 

Sector count (15-8)

 

 

SC

 

 

 

Sector count (7-0)

 

 

FR EXP

 

 

 

 

 

xx

 

 

 

FR

 

 

 

 

 

xx

 

 

 

At command completion (Shadow Block Registers contents to be read)

ST

 

 

 

Status information

 

 

 

 

 

 

 

 

 

DH

1

L

1

 

x

 

xx

 

 

 

 

 

 

 

 

CH EXP

 

 

 

 

LBA (47-40)

 

CH

 

 

 

 

LBA (23-16)

 

CL EXP

 

 

 

 

LBA (39-32)

 

CL

 

 

 

 

LBA (15-8)

 

SN EXP

 

 

 

 

LBA (31-24)

 

SN

 

 

 

 

LBA (7-0)

 

SC EXP

 

 

 

 

xx

 

SC

 

 

 

 

xx

 

ER

 

 

 

Error information

 

 

 

 

 

 

 

 

 

C141-E280

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