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The Complete Guide on SCSI |
Here's a really great Glossary:
SCSI Glossary: Practical Definitions and Terminologies
http://www.paralan.com/glos.html
Abbreviation of Small Computer System Interface. Pronounced "scuzzy," SCSI is a parallel interface standard used by Apple Macintosh computers, PCs, and many UNIX systems for attaching peripheral devices to computers. Nearly all Apple Macintosh computers, excluding only the earliest Macs and the recent iMac, come with a SCSI port for attaching devices such as disk drives and printers.
SCSI interfaces provide for faster data transmission rates (up to 80 megabytes per second) than standard serial and parallel ports. In addition, you can attach many devices to a single SCSI port, so that SCSI is really an I/O bus rather than simply an interface.
Although SCSI is an ANSI standard, there are many variations of it, so two SCSI interfaces may be incompatible. For example, SCSI supports several types of connectors.
While SCSI has been the standard interface for Macintoshes, the iMac comes with IDE, a less expensive interface, in which the controller is integrated into the disk or CD-ROM drive. Other interfaces supported by PCs include enhanced IDE and ESDI for mass storage devices, and Centronics for printers. You can, however, attach SCSI devices to a PC by inserting a SCSI board in one of the expansion slots. Many high-end new PCs come with SCSI built in. Note, however, that the lack of a single SCSI standard means that some devices may not work with some SCSI boards.
The following varieties of SCSI are currently implemented:
*SCSI-1: Uses an 8-bit bus, and supports data rates of 4 MBps
*SCSI-2: Same as SCSI-1, but uses a 50-pin connector instead of a 25-pin connector, and supports multiple devices. This is what most people mean when they refer to plain SCSI.
*Wide SCSI: Uses a wider cable (168 cable lines to 68 pins) to support 16-bit transfers.
*Fast SCSI: Uses an 8-bit bus, but doubles the clock rate to support data rates of 10 MBps.
*Fast Wide SCSI: Uses a 16-bit bus and supports data rates of 20 MBps.
*Ultra SCSI: Uses an 8-bit bus, and supports data rates of 20 MBps.
*SCSI-3: Uses a 16-bit bus and supports data rates of 40 MBps. Also called Ultra Wide SCSI.
*Ultra2 SCSI: Uses an 8-bit bus and supports data rates of 40 MBps.
Wide Ultra2 SCSI: Uses a 16-bit bus and supports data rates of 80 MBps.
For internet.com pages about SCSI, . Also, check out the following links!
All About SCSI
http://www.hardwarecentral.com/hardwarecentral/print/36/
Provides an introduction to SCSI and discusses SCSI evolution, standards,
termination, and configuration.
Adaptec's home page
http://www.adaptec.com/
Home page of Adaptec, supplier of network, server, desktop, portable,
chip solutions as well as FireWire host adapters. Their home page contains
detailed product descriptions, company information, software demos and
upgrades, drivers, a developer site, and a section on emerging technology.
Also includes an Adaptec SCSI product selector.
Hard Disk Interfaces and Configuration
http://www.pcguide.com/ref/hdd/if/index.htm
Describes the different major interface standards currently used by
hard disks (and other devices). Provides sections about the IDE/ATA and
SCSI interfaces. This page is from "The PC Guide."
A Visual Guide to SCSI Connectors
http://www.scsita.org/Pictures.html
Displays diagrams of common SCSI bus connectors.
Article on the performance of SCSI and EIDE hard drives
http://www.zdnet.com/pcmag/pclabs/report/r960702a.htm
PC Lab article describing how SCSI drives perform relative to Enhanced
IDE models.
Digital Interactive
Solutions Limited
http://www.digital-interact.co.uk/
Home page of Digital Interactive Solutions Limited, manufacturer of
tape storage products and a range of modern tape drives and sub-systems.
The site offers company and product information as well as technical reference
information.
Disk FAQs
http://www.seagate.com/support/
Contains a collection of ATA (IDE), DDO, SCSI, Macintosh, and FAT32
FAQs from Seagate Technology.
Gary Field's SCSI Info Central
http://www.scsifaq.org/
Contains links to the comp.periphs.scsi FAQ, companies, and various
related organizations.
SCSI diagnostic tools
http://www.cocomp.com/scsipro/
Describes CoComp's SCSI Pro - SCSI diagnostic utility.
SCSI Explorer
http://www.scsi.org/
PLUS TOP TEN SCSI LINKS!
A list of annotated links to all things retated to SCSI.
SCSI Just Keeps On Rolling
http://www.zdnet.com/pcmag/pctech/content/17/05/tu1705.001.html
PC Magazine article (March 1998) that examines the process by which
the SCSI interface transfers data among SCSI devices. A sidebar explores
the different types of SCSI and describes how SCSI works.
SCSI Trade Association Home Page
http://www.scsita.org/
Includes news items, white papers, articles and specifications, as
well as an area with answers to technical questions about the SCSI interface.
SCSI vs. Ultra DMA
http://www.adaptec.com/technology/benchmark/scsivudma.html
Offers an analysis comparing SCSI and Ultra DMA. This page is hosted
by Adaptec, Inc.
Small Computer Systems Interface (SCSI) Overview
http://www.pcguide.com/ref/hdd/if/scsi/index.htm
Describes SCSI standards, protocols and transfer modes, host adapters,
and configuration and cabling. This page is from "The PC Guide."
Ultra2 SCSI LVD Drives
http://www.seagate.com/support/
Describes Low Voltage Differential (LVD) devices. This page is hosted
by Seagate Technology, Inc.
What Kind of SCSI Do I Have?
http://www.paralan.com/sediff.html
Helps users determine if they have single-ended SCSI or a differential
SCSI interface.