4.4 Maintenance, Diagnostic Commands

4.4.5 READ LONG (3E)

 

Bit

7

6

 

5

4

 

3

 

2

1

0

Byte

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

X'3E'

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

0

0

0

0

0

 

0

CORRCT

0

 

 

 

 

 

 

 

 

 

2

 

 

 

Logical Block Address (MSB)

 

 

 

 

 

 

 

 

 

 

 

3

 

 

 

Logical Block Address

 

 

 

 

 

 

 

 

 

 

 

4

 

 

 

Logical Block Address

 

 

 

 

 

 

 

 

 

 

 

5

 

 

 

Logical Block Address (LSB)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6

 

0

0

0

0

0

 

0

0

0

 

 

 

 

 

 

 

 

7

 

 

 

Transfer Byte Length (MSB)

 

 

 

 

 

 

 

 

 

 

 

8

 

 

 

Transfer Byte Length (LSB)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

9

 

0

0

 

0

0

0

 

0

0

0

 

 

 

 

 

 

 

 

 

 

 

 

 

This command reads the logical data block data and its ECC byte, specified in the "Logical block address" field in the CDB, from the disk media and transfers it to the INIT. Normally, this command is used in combination with the WRITE LONG command to perform checks of the ECC function. The operation object in this command is 1 data block only.

Remark: The Pad Byte and Sync Mark patterns are not included in the transfer data.

When "0" is specified in bit 1 of CDB byte 1, the "CORRCT (Corrected)" bit, the HDD does not implement ECC correction processing of data read from the disk media. When "1" is specified in the "CORRCT (Corrected)" bit, data errors that can be corrected by ECC are transferred to the INIT after being corrected in the HDD's data buffer.

When the "Transfer byte length" specifies zero, this command executes a seek operation of the cylinder/track existing in the logical data block which is specified in the "Logical block address" field in the CDB., then is terminated without data being transferred to the INIT.

When a length (other than zero) which does not match the data format on the disk media is specified in the "Transfer byte length" field in the CDB, this command is terminated with a CHECK CONDITION status without executing a data transfer to the INIT. At this time, the sense data indicate the following contents and the INIT can determine the correct "Transfer byte length" from their contents.

C141-C013

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Fujitsu MBA3073RC, MBC2036RC, MBC2073RC, MBA3300RC, MBA3147RC specifications Read Long 3E