Western Digital WDE2170 - Manual (Page 31)

WD Enterprise WDE2170/WDE4360 Advanced Product Features
4079-001045 Rev. B RELEASED 04-08-97 23
3.13. Zoned Recording
The drives employ zoned recording to increase data density on the outer tracks of the
drive. Zoned recording allows the adjustment of the number of sectors per track, which
provides storage of more sectors on the larger, outer tracks. Formatting packs data
uniformly throughout the surface of the platter by dividing the outer tracks into more
sectors. With more bytes per track, the drive reads the data in the outer zones at a faster
rate.
3.14. Headerless Format
Headerless format is also known as ID-less or No-ID sector format. This format removes
the header (or ID fields) and all the information within the header (track format) to
provide a dramatic increase in user capacity. Our advanced, integrated SCSI controller
assumes the task of determining the physical location of each sector.
3.15. LED Support
If an LED is installed on the drive, the following occurs:

 The LED is turned off as soon as power is applied. If Auto Start is enabled, the LED
is on while the drive is spinning up and turned off when Auto Start is completed.

 The LED is on when a SCSI command is being executed.

 The LED flashes when an error prohibits the use of the SCSI interface.