Western Digital Purple PR1000M Technical Reference Manual page 12

D F
ESCRIPTION AND EATURES
hard drives.
Pre-emptive Wear Leveling (PWL) —This WD feature provides a solution for

protecting the recording media against mechanical wear. In cases where the
drive is so busy with incoming commands that it is forced to stay in a same
cylinder position for a long time, the PWL control engine initiates forced seeks so
that disk lubricant maintains an even distribution and does not become depleted.
This feature ensures reliability for applications that perform a high incidence of
read/write operations at the same physical location on the disk.
Femto Slider — These drives incorporate the femto slider form factor in which the

read/write head is mounted on the small, lightweight femto slider which allows
the head to move more quickly from track to track on the disk.
S.M.A.R.T. Command Transport (SCT) — The SCT Command Transport feature

set provides a method for a host to send commands and data to a device and for
a device to send data and status to a host using log pages.
World Wide Name (WWN) — The World Wide Name (WWN) defined in ATA/

ATAPI-7 is a modification of the IEEE extended unique identifier 64 bit standard
(EUI-64) and is comprised of three major components: naming authority,
organizationally unique identifier (OUI) and serial number. WD's OUI is 0014EEh.
Reliability Features Set-Data Lifeguard™ — Representing WD's ongoing

commitment to data protection, Data Lifeguard includes features that enhance
the drive's ability to prevent data loss. Data Lifeguard data protection utilities
include thermal management, an environmental protection system, and
embedded error detection and repair features that automatically detect, isolate,
and repair problem areas that may develop over the extended use of the hard
drive. With these enhanced data reliability features, the drive can perform more
accurate monitoring, error repair, and deliver exceptional data security.
Hot Plug Support — SATA supports hot plugging (also known as "hot

swapping"), the ability to swap out a failed hard drive without having to power
down the system or reboot. This capability contributes to both data availability
and serviceability without any associated downtime, making it a critical feature
for extending SATA into enterprise applications.
Active LED Status — The drive supports external LED requirements. It provides an

activity LED output which is ON during command execution and OFF otherwise.
Fluid Dynamic Bearings (FDB) — Bearing design that incorporates a layer of high-

viscosity lubricant instead of ball bearings in the hard drive spindle motor. As an
alternative to conventional ball bearing technology, FDB designs provide
increased non-operational shock resistance, speed control, and improved
acoustics.
Staggered Spin-Up — SATA 3 Gb/s feature that allows the system to control

whether the drive will spin up immediately or wait until the interface is fully ready
(available for specific OEM configurations).
CacheFlow™ —WD's unique, multi-generation caching algorithm evaluates the

way data is read from and written to the drive and adapts "on-the-fly" to the
optimum read and write caching methods. CacheFlow minimizes disk seek
operations and overheads due to rotational latency. CacheFlow supports
sequential and random write cache. With write cache and other CacheFlow
features, the user can cache both read and write data. The cache can hold
multiple writes and collectively write them to the hard disk.
2
RELEASED 5/8/17 (WD CONFIDENTIAL)
PR1000M
2679-800020-A03