A T L A S 1 0 K 3 6 G B QUANTUM Native| Translation ------+-----+-----+----- Form 3.5"/HH Cylinders | | | Capacity form/unform 36000/ MB Heads | | | Seek time / track 5.0/ ms Sector/track | | | Controller ULTRA2 SCSI LVD Precompensation Cache/Buffer KB Landing Zone Data transfer rate MB/S int Bytes/Sector 512 160.000 MB/S ext Recording method operating | non-operating -------------+-------------- Supply voltage Temperature *C | Power: sleep W Humidity % | standby W Altitude km | idle W Shock g | seek W Rotation RPM 10000 read/write W Acoustic dBA spin-up W ECC Bit MTBF h Warranty Month Lift/Lock/Park YES Certificates
QUANTUM ULTRA160/M SCSI
What is Ultra160/m SCSI?
The ANSI standards T10 committee is revising the SCSI Parallel
Interface (SPI-3). This document is the basis of the Ultra160/m SCSI
technology. Evolutionary changes have been made to the existing
SCSI protocol (SPI-2) to increase performance, manageability, and
reliability. All changes are incremental, and existing SCSI
protocols are maintained for backward compatibility. Three new
underlying components of Ultra160/m SCSI are Double Transition
Clocking, Cyclical Redundancy Checks (CRC), and Domain Validation.
What technology Enables Ultra160/m SCSI?
Ultra160/m SCSI doubles transfer rates to 160 Megabytes per second
by using both edges of the request/acknowledge signal to clock data.
This creative solution provides designers with the choice of
improving speed, reliability or connectivity. It allows system
designers to choose bus bandwidths up to 160 MB/second using
existing Ultra2 SCSI cable plants. Alternatively, this technology
lets designers maintain Ultra2 SCSI speeds (80 MB/second) and
improve reliability by lowering clock speed, allowing more margin for
ASICs and cables.
Other Ultra160/m SCSI improvements include automatic tests of the
interface's performance level for increased manageability and the
addition of CRC for reliable data transmission. When Ultra160/m SCSI
is used with LVD signaling, cable lengths of 12 meters are maintained
providing full backward compatibility.
Double Transition Clocking
Double transition clocking changes the digital protocol to use
both edges of the SCSI request/acknowledge signal to clock data.
Data transfer rates can be doubled simply by increasing the speed of
only the data lines. For example, request/acknowledge signal on
Ultra2 SCSI runs at 40 MHz, while data runs at only 20 MHz, or 80
MB/second on a 16-bit wide bus. By using both edges of the same 40
MHz request/acknowledge signal, the data rate can be increased
to 40 MHz, or 160 MB/second on a 16-bit wide bus.
Choosing the Speed Advantage with Double Transition Clocking
Double Transition Clocking doubles the Ultra2 SCSI data transfer
rates from 80 MB/second to 160 MB/second. Interface bandwidth is
an essential ingredient for Windows NT and UNIX workstations, video
and web servers, and storage area networks (SANs).