- Community Home
- >
- Storage
- >
- Legacy
- >
- Disk
- >
- What is the difference? SCSI vs. scsi diff
Categories
Company
Local Language
Forums
Discussions
Forums
- Data Protection and Retention
- Entry Storage Systems
- Legacy
- Midrange and Enterprise Storage
- Storage Networking
- HPE Nimble Storage
Discussions
Forums
Discussions
Discussions
Discussions
Forums
Forums
Discussions
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
- BladeSystem Infrastructure and Application Solutions
- Appliance Servers
- Alpha Servers
- BackOffice Products
- Internet Products
- HPE 9000 and HPE e3000 Servers
- Networking
- Netservers
- Secure OS Software for Linux
- Server Management (Insight Manager 7)
- Windows Server 2003
- Operating System - Tru64 Unix
- ProLiant Deployment and Provisioning
- Linux-Based Community / Regional
- Microsoft System Center Integration
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Community
Resources
Forums
Blogs
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-10-2005 03:16 PM
тАО05-10-2005 03:16 PM
But, I would like to know the diffence...
What each does.
Solved! Go to Solution.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-10-2005 03:54 PM
тАО05-10-2005 03:54 PM
Re: What is the difference? SCSI vs. scsi diff
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-10-2005 04:27 PM
тАО05-10-2005 04:27 PM
SolutionYou have the Single Ended SCSI and the Differential SCSI and the main difference is in the type of the signalling used.
In SE a positive voltage is a "one", and a zero voltage (ground) is a "zero" while in Differential SCSI, two lines are used. For a logical "zero", zero voltage is sent on both wires. For a logical "one", the first wire of each signal pair contains a positive voltage, similar to the signal on an SE bus, but not necessarily at the same voltage.
The second wire contains the electrical opposite of the first wire. The circuitry at the receiving device takes the difference between the two signals sent, and thus sees a relatively high voltage for a one, and a zero voltage for a zero.
in short it uses a diffential voltage for signalling.
Regards,
Naveej
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-10-2005 04:49 PM
тАО05-10-2005 04:49 PM
Re: What is the difference? SCSI vs. scsi diff
Have a look at http://www.pctechguide.com/26interfaces_SCSI_evolution.htm.
Regards,
Suraj
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-10-2005 05:08 PM
тАО05-10-2005 05:08 PM
Re: What is the difference? SCSI vs. scsi diff
The old 'differential' is called "HVD" (high voltage differential) these days and is completely incompatible with "SE" (single ended) or "LVD" (low voltage differential).
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-10-2005 05:28 PM
тАО05-10-2005 05:28 PM
Re: What is the difference? SCSI vs. scsi diff
See attached which is related to SCSI.
It includes connector pictures.
Regds
TT
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-10-2005 10:14 PM
тАО05-10-2005 10:14 PM
Re: What is the difference? SCSI vs. scsi diff
"Quoted from Gregory Fruth:
There are many many types of SCSI. Each type
has a "speed", a "bus width", and a "signal type".
The "speeds" are: (None), Fast, Ultra, Ultra2,
Ultra3/Ultra160, and Ultra320. "(None)" refers
to the speed below "Fast"; it was the only speed
defined at the time so there was no need to give
it a name. For consistency they ought to have
renamed it "Slow" or "Single Speed" or "1x" or
something when "Fast" came out.
The "bus widths" are (None)/Narrow and
Wide/(None). Again, originally SCSI only had
"Narrow", so the term "Narrow" wasn't used at
the time. If you didn't specify "Narrow" or "Wide"
it was assumed to be "Narrow". However, the
newer SCSI types are "Wide" only, so if you
don't say "Narrow" or "Wide" you can't assume
which one it is unless you know it's Ultra3, for
example, in which case it has to be "Wide".
The "signal types" are Single-Ended (SE), Low
Voltage Differential (LVD) and High Voltage
Differential (HVD). These days HVD has almost
totally vanished, and most people are pretty good
about stating whether a device is SE or LVD.
The term "FWD" stands for "Fast Wide Differential".
The "Differential" in that case is HVD (LVD hadn't
been developed yet). The term "UWSE" stands for
Ultra Wide Single Ended."
See also:
http://www.scsita.org/terms/scsiterms.html
http://www.scsita.org/terms/SCSI_Overview.html
and (from Harry Brown):
http://scsifaq.paralan.com/
Pete
Pete
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО05-11-2005 06:14 AM
тАО05-11-2005 06:14 AM