9.9Reassign Function

The reassign Function is used with read commands and write commands. The sectors of data for reassignment are prepared as the spare data sector.

This reassignment information is registered internally, and the information is available right after completing the reassign function. Also the information is used on the next power on reset or hard reset.

If the number of the spare sector reaches 0 sectors, the reassign function will be disabled automatically.

The spare tracks for reassignment are located at regular intervals from Cylinder 0. As a result of reassignment, the physical location of logically sequenced sectors will be dispersed.

9.9.1Auto Reassign Function

The sectors those show some errors may be reallocated automatically when specific conditions are met. The spare tracks for reallocation are located at regular intervals from Cylinder 0. The conditions for auto-reallocation are described below.

Non recovered write errors

When a write operation can not be completed after the Error Recovery Procedure (ERP) is fully carried out, the sector(s) are reallocated to the spare location. An error is reported to the host system only when the write cache is disabled and the auto reallocation is failed.

If the write cache function is ENABLED, and when the number of available spare sectors reaches 0 sectors, both auto reassign function and write cache function are disabled automatically.

Non recovered read errors

When a read operation is failed after defined ERP is fully carried out, a hard error is reported to the host system. This location is registered internally as a candidate for the reallocation. When a registered location is specified as a target of a write operation, a sequence of media verification is performed automatically. When the result of this verification meets the criteria, this sector is reallocated.

Recovered read errors

When a read operation for a sector failed once then recovered at the specific ERP step, this sector of data is reallocated automatically. A media verification sequence may be run prior to the relocation according to the pre-defined conditions.

Hitachi hard disk drive specifications

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Hitachi HCS721032CLA382, HCS721050CLA382 Auto Reassign Function, Non recovered write errors, Non recovered read errors

HCS721016CLA382, HCS721050CLA382, HCS721025CLA382, HDP725050GLA360, HUA722050CLA330/1 specifications

Hitachi's lineup of hard disk drives, including models such as HDS721075CLA632, HDS721032CLA362, HDS721032CLA662, HDS721050CLA362, and DSDS7210C09EN-04, offers a variety of features catering to different storage needs. These drives are widely recognized for their reliability, performance, and efficiency, making them suitable for both consumer and enterprise applications.

The HDS721075CLA632 model, with a capacity of 750GB, strikes a balance between performance and storage capabilities. It operates at 7200 RPM, ensuring quick access to data while maintaining low latency. Its 32MB cache enhances data transfer rates and improves overall system responsiveness. This HDD is particularly useful for gaming, multimedia, and office applications, allowing users to store a substantial amount of data with quick retrieval times.

The HDS721032CLA362 and HDS721032CLA662 share many similarities and are both designed for budget-conscious consumers. With a capacity of 320GB and a 7200 RPM, they offer efficient storage solutions for everyday tasks. The 32MB cache buffer enables efficient caching of frequently accessed files, providing a smooth experience for users.

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On the other hand, the DSDS7210C09EN-04 is a part of Hitachi's enterprise-oriented offerings. This drive is engineered for demanding applications, featuring advanced technologies such as error recovery controls and enhanced data protection features. With a focus on reliability and performance, the DSDS7210C09EN-04 serves well in server environments and for high-performance computing.

Hitachi's hard drives incorporate various technologies that enhance their performance and durability. Features such as staggered start-up, which gradually powers on the drive, help minimize power surges and increase the longevity of the device. Moreover, Hitachi's commitment to quality ensures that each drive undergoes rigorous testing, guaranteeing functionality and reliability.

Overall, the diverse range of models from Hitachi provides effective solutions for anyone from casual users to enterprises, combining storage capacity with advanced technologies to meet the evolving demands of modern data storage.