5.3 Host Commands

(2) READ SECTOR(S) (X’20’ or X’21’)

This command reads data of sectors specified in the Sector Count register from the address specified in the Device/Head, Cylinder High, Cylinder Low and Sector Number registers. Number of sectors can be specified from 1 to 256 sectors. To specify 256 sectors reading, ‘00’ is specified. For the DRQ, INTRQ, and BSY protocols related to data transfer, see Subsection 5.4.1.

If the head is not on the track specified by the host, the device performs an implied seek. After the head reaches to the specified track, the device reads the target sector.

If an error occurs, retry reads are attempted to read the target sector before reporting an error, irrespective of the R bit setting.

The DRQ bit of the Status register is always set prior to the data transfer regardless of an error condition.

Upon the completion of the command execution, command block registers contain the cylinder, head, and sector addresses (in the CHS mode) or logical block address (in the LBA mode) of the last sector read.

If an unrecoverable error occurs in a sector, the read operation is terminated at the sector where the error occurred. Command block registers contain the cylinder, the head, and the sector addresses of the sector (in the CHS mode) or the logical block address (in the LBA mode) where the error occurred, and remaining number of sectors of which data was not transferred.

At command issuance (I/O registers setting contents)

1F7H(CM)

0

0

1

0

0

0

0

R

 

 

 

 

 

 

 

1F6H(DH)

x

L

x

DV

Start head No. / LBA

 

 

 

 

 

 

[MSB]

 

 

 

 

 

 

 

 

 

 

 

 

1F5H(CH)

Start cylinder No. [MSB] / LBA

 

 

 

1F4H(CL)

Start cylinder No. [LSB] / LBA

 

 

 

1F3H(SN)

Start sector No. / LBA [LSB]

 

 

 

1F2H(SC)

Transfer sector count

 

 

 

 

1F1H(FR)

xx

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C141-E221

5-21

Page 96 Page 98
Page 97
Image 97
Fujitsu MHV2060AS, MHV2080AS, MHV2040AS manual Read Sectors X’20’ or X’21’, Msb
Page 96 Page 98

MHV2060AS, MHV2080AS, MHV2040AS specifications

Fujitsu's MHV series of hard disk drives, specifically the MHV2040AS, MHV2080AS, and MHV2060AS models, are designed to deliver efficient performance and reliability for a range of applications, particularly in desktop computing and entry-level servers. Each of these drives adheres to the Serial ATA (SATA) interface, which ensures compatibility across a wide range of systems and is known for its cost-effectiveness and simplicity.

The MHV2040AS features a storage capacity of 40GB, making it suitable for basic computing tasks including document editing, web browsing, and media playback. The MHV2060AS steps it up with a 60GB capacity, allowing for increased data storage needs while still maintaining a high level of performance. The largest of the trio, the MHV2080AS, offers an impressive 80GB of space, positioning it well for users who require additional room for applications, games, and multimedia files.

All drives in this series are equipped with a rotational speed of 5400 RPM, which strikes a balance between speed and power consumption. This speed is adequate for everyday tasks and allows for quick boot times and file access, making them ideal for home and small office environments. Additionally, the drives feature an average latency of 5.5 milliseconds, contributing to their overall performance in retrieving data.

In terms of technology, the MHV series employs a fluid dynamic bearing (FDB) motor, which not only enhances reliability but also reduces noise levels during operation. The FDB technology helps improve the longevity of the drives by minimizing wear on mechanical components. This characteristic is particularly important for users seeking quieter drives, especially in work environments that require minimal disruption.

The drives also incorporate advanced power management features that significantly reduce power consumption, making them an environmentally friendly choice for users mindful of their carbon footprint. These drives are equipped with energy-saving modes that optimize their performance when not in full use, ensuring lower operational costs and longer lifespan.

Overall, the Fujitsu MHV2040AS, MHV2080AS, and MHV2060AS hard drives provide a solid solution for users looking for dependable storage with a range of capacities to fit their needs. Their performance, combined with noise reduction technologies and energy efficiency, makes them a notable choice for various computing environments, from single-user desktops to small business applications.
Top Page Image Contents