9.4Power Management Feature

The power management feature set permits a host to modify the behavior in a manner which reduces the power required to operate. The power management feature set provides a set of commands and a timer that enables a device to implement low power consumption modes.

HDS7210xxCLA3yz / HUA7220xxCLA33z / HCS5C10xxCLA382 / HCS7210xxCLA3y2 / HDS5C10xxCLA382 implement the following set of functions.

1.A Standby timer

2.Idle command

3.Idle Immediate command

4.Sleep command

5.Standby command

6.Standby Immediate command

9.4.1 Power Mode

The lowest power consumption when the device is powered on occurs in Sleep Mode. When in sleep mode, the device requires a reset to be activated.

In Standby Mode the device interface is capable of accepting commands, but as the media may not immediately accessible, there is a delay while waiting for the spindle to reach operating speed.

In Idle Mode the device is capable of responding immediately to media access requests.

In Active Mode the device is under executing a command or accessing the disk media with read look-ahead function or writes cache function.

9.4.2 Power Management Commands

The Check Power Mode command allows a host to determine if a device is currently in, going to or leaving standby mode.

The Idle and Idle Immediate commands move a device to idle mode immediately from the active or standby modes. The idle command also sets the standby timer count and starts the standby timer.

The Standby and Standby Immediate commands move a device to standby mode immediately from the active or idle modes. The standby command also sets the standby timer count.

The Sleep command moves a device to sleep mode. The device's interface becomes inactive at the completion of the sleep command. A reset is required to move a device out of sleep mode. When a device exits sleep mode it will enter Standby mode.

9.4.3 Standby timer

The standby timer provides a method for the device to automatically enter standby mode from either active or idle mode following a host programmed period of inactivity. If the device is in the active or idle mode, the device waits for the specified time period and if no command is received, the device automatically enters the standby mode.

If the value of SECTOR COUNT register on Idle command or Standby command is set to 00h, the standby timer is disabled.

Hitachi hard disk drive specifications

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Hitachi HDS721050CLA362, HCS721050CLA382 Power Management Feature, Power Mode, Power Management Commands, Standby timer

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.

Another notable model is the HDS721050CLA362, which features a capacity of 500GB. Like its counterparts, this drive operates at a speed of 7200 RPM and utilizes a 32MB cache, which ensures optimal performance for data-heavy applications. This model stands out for its energy efficiency, resulting in lower operational costs, making it an appealing choice for businesses and energy-conscious consumers alike.

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.