| slovo | definícia |
scsi
(wn) | SCSI
n 1: interface consisting of a standard port between a computer
and its peripherals that is used in some computers [syn:
small computer system interface, SCSI] |
scsi
(foldoc) | Small Computer System Interface
SASI
SCSI
(SCSI) /skuh'zee/, /sek'si/ The most
popular processor-independent standard, via a parallel bus,
for system-level interfacing between a computer and
intelligent devices including hard disks, floppy disks,
CD-ROM, printers, scanners, and many more.
SCSI can connect multiple devices to a single SCSI adapter
(or "host adapter") on the computer's bus. SCSI transfers bits
in parallel and can operate in either asynchronous or
synchronous modes. The synchronous transfer rate is up to
5MB/s. There must be at least one target and one
initiator on the SCSI bus.
SCSI connections normally use "single ended" drivers as
opposed to differential drivers. Single ended SCSI can
suport up to six metres of cable. Differential ended SCSI can
support up to 25 metres of cable.
SCSI was developed by Shugart Associates, which later became
Seagate. SCSI was originally called SASI for "Shugart
Associates System Interface" before it became a standard.
Due to SCSI's inherent protocol flexibility, large support
infrastructure, continued speed increases and the acceptance
of SCSI Expanders in applications it is expected to hold its
market.
The original standard is now called "SCSI-1" to distinguish it
from SCSI-2 and SCSI-3 which include specifications of
Wide SCSI (a 16-bit bus) and Fast SCSI (10 MB/s transfer).
SCSI-1 has been standardised as ANSI X3.131-1986 and
ISO/IEC 9316.
A problem with SCSI is the large number of different
connectors allowed. Nowadays the trend is toward a 68-pin
miniature D-type or "high density" connector (HD68) for
Wide SCSI and a 50-pin version of the same connector (HD50)
for 8-bit SCSI (Type 1-4, pin pitch 1.27 mm x 2.45 mm).
50-pin ribbon cable connectors are also popular for internal
wiring (Type 5, pin pitch 2.54 mm x 2.54 mm). {Apple
Computer} used a 25-pin connector on the Macintosh computer
but this connector causes problems with high-speed equipment.
Original SCSI implementations were highly incompatible with
each other.
ASPI is a standard Microsoft Windows interface to SCSI
devices.
Usenet newsgroup: news:comp.periphs.scsi.
SCSI Trade Association & FAQ (http://scsita.org/).
["System" or "Systems"?]
(1999-03-30)
|
scsi
(jargon) | SCSI
n.
[Small Computer System Interface] A bus-independent standard for
system-level interfacing between a computer and intelligent devices.
Typically annotated in literature with ‘sexy’ (/sek'see/), ‘sissy’ (/sis´ee
/), and ‘scuzzy’ (/skuh'zee/) as pronunciation guides — the last being the
overwhelmingly predominant form, much to the dismay of the designers and
their marketing people. One can usually assume that a person who pronounces
it /S-C-S-I/ is clueless.
|
scsi
(vera) | SCSI
Small Computer Systems Interface (SCSI)
|
| | podobné slovo | definícia |
scsi
(wn) | SCSI
n 1: interface consisting of a standard port between a computer
and its peripherals that is used in some computers [syn:
small computer system interface, SCSI] |
advanced scsi peripheral interface
(foldoc) | Advanced SCSI Peripheral Interface
ASPI
(ASPI) A set of libraries designed to
provide programs running under Microsoft Windows with a
consistent interface for accessing SCSI devices. ASPI has
become a de facto standard.
The ASPI layer is a collection of programs (DLLs) that
together implement the ASPI interface. Many problems are
caused by device manufacturers packaging incomplete sets of
these DLLs with their hardware, often with incorrect date
stamps, causing newer versions to get replaced with old.
ASPICHK from Adaptec will check the ASPI components installed
on a computer.
The latest ASPI layer as of March 1999 is 1014.
The ATAPI standard for IDE devices makes them look to the
system like SCSI devices and allows them to work through ASPI.
(http://resource.simplenet.com/primer/aspi.htm).
(1999-03-30)
|
fast scsi
(foldoc) | Fast SCSI
A variant on the SCSI-2 bus. It uses the same
8-bit bus as the original SCSI-1 but runs at up to 10MB/s -
double the speed of SCSI-1.
(1994-11-24)
|
scsi
(foldoc) | Small Computer System Interface
SASI
SCSI
(SCSI) /skuh'zee/, /sek'si/ The most
popular processor-independent standard, via a parallel bus,
for system-level interfacing between a computer and
intelligent devices including hard disks, floppy disks,
CD-ROM, printers, scanners, and many more.
SCSI can connect multiple devices to a single SCSI adapter
(or "host adapter") on the computer's bus. SCSI transfers bits
in parallel and can operate in either asynchronous or
synchronous modes. The synchronous transfer rate is up to
5MB/s. There must be at least one target and one
initiator on the SCSI bus.
SCSI connections normally use "single ended" drivers as
opposed to differential drivers. Single ended SCSI can
suport up to six metres of cable. Differential ended SCSI can
support up to 25 metres of cable.
SCSI was developed by Shugart Associates, which later became
Seagate. SCSI was originally called SASI for "Shugart
Associates System Interface" before it became a standard.
Due to SCSI's inherent protocol flexibility, large support
infrastructure, continued speed increases and the acceptance
of SCSI Expanders in applications it is expected to hold its
market.
The original standard is now called "SCSI-1" to distinguish it
from SCSI-2 and SCSI-3 which include specifications of
Wide SCSI (a 16-bit bus) and Fast SCSI (10 MB/s transfer).
SCSI-1 has been standardised as ANSI X3.131-1986 and
ISO/IEC 9316.
A problem with SCSI is the large number of different
connectors allowed. Nowadays the trend is toward a 68-pin
miniature D-type or "high density" connector (HD68) for
Wide SCSI and a 50-pin version of the same connector (HD50)
for 8-bit SCSI (Type 1-4, pin pitch 1.27 mm x 2.45 mm).
50-pin ribbon cable connectors are also popular for internal
wiring (Type 5, pin pitch 2.54 mm x 2.54 mm). {Apple
Computer} used a 25-pin connector on the Macintosh computer
but this connector causes problems with high-speed equipment.
Original SCSI implementations were highly incompatible with
each other.
ASPI is a standard Microsoft Windows interface to SCSI
devices.
Usenet newsgroup: news:comp.periphs.scsi.
SCSI Trade Association & FAQ (http://scsita.org/).
["System" or "Systems"?]
(1999-03-30)
|
scsi adapter
(foldoc) | SCSI adapter
SCSI controller
SCSI interface
(Or "host adapter") A device that communicates
between a computer and its SCSI peripherals. The SCSI
adapter is usually assigned SCSI ID 7. It is often a
separate card that is connected to the computer's bus
(e.g. PCI, ISA, PCMCIA) though increasinly, SCSI
adapters are built in to the motherboard. Apart from being
cheaper, busses like PCI are too slow to keep up with the
newer SCSI standards like Ultra SCSI and Ultra-Wide SCSI.
There are several varieties of SCSI (and their connectors) and
an adapter will not support them all.
The performance of SCSI devices is limited by the speed of the
SCSI adapter and its connection to the computer. An adapter
that plugs into a parallel port is unlikely to be as fast as
one incorporated into a motherboard. Fast adapters use DMA
or bus mastering.
Some SCSI adapters include a BIOS to allow PCs to boot
from a SCSI hard disk, if their own BIOS supports it.
Adaptec make the majority of SCSI chipsets and many of the
best-selling adapters.
Note that it is not a "SCSI controller" - it does not control
the devices, and "SCSI interface" is redundant - the "I" of
"SCSI" stands for "interface".
(1999-11-24)
|
scsi adaptor
(foldoc) | SCSI adaptor
Less common spelling of SCSI adapter.
|
scsi controller
(foldoc) | SCSI adapter
SCSI controller
SCSI interface
(Or "host adapter") A device that communicates
between a computer and its SCSI peripherals. The SCSI
adapter is usually assigned SCSI ID 7. It is often a
separate card that is connected to the computer's bus
(e.g. PCI, ISA, PCMCIA) though increasinly, SCSI
adapters are built in to the motherboard. Apart from being
cheaper, busses like PCI are too slow to keep up with the
newer SCSI standards like Ultra SCSI and Ultra-Wide SCSI.
There are several varieties of SCSI (and their connectors) and
an adapter will not support them all.
The performance of SCSI devices is limited by the speed of the
SCSI adapter and its connection to the computer. An adapter
that plugs into a parallel port is unlikely to be as fast as
one incorporated into a motherboard. Fast adapters use DMA
or bus mastering.
Some SCSI adapters include a BIOS to allow PCs to boot
from a SCSI hard disk, if their own BIOS supports it.
Adaptec make the majority of SCSI chipsets and many of the
best-selling adapters.
Note that it is not a "SCSI controller" - it does not control
the devices, and "SCSI interface" is redundant - the "I" of
"SCSI" stands for "interface".
(1999-11-24)
|
scsi id
(foldoc) | SCSI ID
The unique address of a SCSI device. SCSI IDs
range from 0 to 7 for 8-bit SCSI systems, 0 to 15 for 16-bit
and 0 to 31 for 32-bit systems. The SCSI adapter is
usually assigned ID 7. A device's SCSI ID is often set by
switches on the device.
(1999-09-01)
|
scsi initiator
(foldoc) | SCSI initiator
initiator
A device that begins a SCSI transaction by
issuing a command to another device (the SCSI target),
giving it a task to perform. Typically a SCSI host adapter is
the initiator but targets may also become initiators.
(1999-02-10)
|
scsi interface
(foldoc) | SCSI adapter
SCSI controller
SCSI interface
(Or "host adapter") A device that communicates
between a computer and its SCSI peripherals. The SCSI
adapter is usually assigned SCSI ID 7. It is often a
separate card that is connected to the computer's bus
(e.g. PCI, ISA, PCMCIA) though increasinly, SCSI
adapters are built in to the motherboard. Apart from being
cheaper, busses like PCI are too slow to keep up with the
newer SCSI standards like Ultra SCSI and Ultra-Wide SCSI.
There are several varieties of SCSI (and their connectors) and
an adapter will not support them all.
The performance of SCSI devices is limited by the speed of the
SCSI adapter and its connection to the computer. An adapter
that plugs into a parallel port is unlikely to be as fast as
one incorporated into a motherboard. Fast adapters use DMA
or bus mastering.
Some SCSI adapters include a BIOS to allow PCs to boot
from a SCSI hard disk, if their own BIOS supports it.
Adaptec make the majority of SCSI chipsets and many of the
best-selling adapters.
Note that it is not a "SCSI controller" - it does not control
the devices, and "SCSI interface" is redundant - the "I" of
"SCSI" stands for "interface".
(1999-11-24)
|
scsi reconnect
(foldoc) | SCSI reconnect
disconnect
The ability of a SCSI initiator to initiate new
transactions before earlier ones have completed. A target or
initiator can disconnect from the bus when it experiences a
delay in completing a task so that another device can use the
bus. It can reconnect later and complete the task.
(1999-02-16)
|
scsi target
(foldoc) | SCSI target
target
A SCSI device that executes a command from a
SCSI initiator to perform some task. Typically the target
is a SCSI peripheral device but the host adapter can also be
a target.
(1999-02-10)
|
scsi-1
(foldoc) | SCSI-1
The original SCSI, as opposed to
SCSI-2 or SCSI-3.
(1995-04-20)
|
scsi-2
(foldoc) | SCSI-2
A version of the SCSI command
specification.
SCSI-2 shares the original SCSI's asynchronous and
synchronous modes and adds a "Fast SCSI" mode ( |
scsi-3
(foldoc) | SCSI-3
An ongoing standardisation effort to
extend the capabilities of SCSI-2. SCSI-3's goals are more
devices on a bus (up to 32); faster data transfer; greater
distances between devices (longer cables); more device classes
and command sets; structured documentation; and a structured
protocol model.
In SCSI-2, data transmission is parallel (8, 16 or 32 bit
wide). This gets increasingly difficult with higher data
rates and longer cables because of varying signal delays on
different wires. Furthermore, wiring cost and drive power
increases with wider data words and higher speed. This has
triggered the move to serial interfacing in SCSI-3. By
embedding clock information into a serial data stream signal
delay problems are eliminated. Driving a single signal also
consumes less driving power and reduces connector cost and
size.
To allow for backward compatibility and for added flexibility
SCSI-3 allows the use of several different transport
mechanisms, some serial and some parallel. The software
protocol and command set is the same for each transport.
This leads to a layered protocol definition similar to
definitions found in networking.
SCSI-3 is therefore in fact the sum of a number of separate
standards which are defined by separate groups. These
standards and groups are currently:
X3T9.2/91-13R2 SCSI-3 Generic Packetized Protocol
X3T9.2/92-141 SCSI-3 Queuing Model
X3T9.2/92-079 SCSI-3 Architecture Model
IEEE P1394 High Performance Serial Bus
X3T9.2/92-106 SCSI-3 Block Commands
X3T9.2/91-189 SCSI-3 Serial Bus Protocol
X3T9.2/92-105 SCSI-3 SCSI-3 Core Commands
SCSI-3 Common Command Set
X3T9.2/92-108 SCSI-3 Graphic Commands
X3T9.2/92-109 SCSI-3 Medium Changer Commands
X3T9.2/91-11 SCSI-3 Interlocked Protocol
X3T9.2/91-10 SCSI-3 Parallel Interface
X3T9.2/92-107 SCSI-3 Stream Commands
SCSI-3 Scanner Commands
Additional Documents for the Fibre Channel are also meant to
be included in the SCSI-3 framework, i.e.:
Fibre Channel SCSI Mapping
Fibre Channel Fabric Requirements
Fibre Channel Low Cost Topologies
X3T9.3/92-007 Fibre Channel Physical and Signalling Interface
Fibre Channel Single Byte Commands
Fibre Channel Cross Point Switch Topology
X3T9.2/92-103 SCSI-3 Fibre Channel Protocol (GPP & SBP)
As all of this is an ongoing effort of considerable
complexity, document structure and workgroups may change. No
final standard is issued yet.
In the meantime a group of manufacturers have proposed an
extension of SCSI-2 called Ultra-SCSI which doubles the
transfer speed of Fast-SCSI to give 20MByte/s on an 8 bit
connection and 40MByte/s on a 16-bit connection.
[Hermann Strass: "SCSI-Bus erfolgreich anwenden",
Franzis-Verlag Muenchen 1993].
(1995-04-19)
|
ultra-scsi
(foldoc) | Ultra-SCSI
An extension of SCSI-2 proposed by a group of
manufacturers which doubles the transfer speed of Fast-SCSI
to give 20MByte/s on an 8-bit connection and 40MByte/s on a
16-bit connection.
(1995-04-19)
|
wide scsi
(foldoc) | Wide SCSI
A variant on the SCSI-2 interface. It
uses a 16-bit bus - double the width of the original SCSI-1
- and therefore cannot be connected to a SCSI-1 bus. It
supports transfer rates up to 20 MB/s, like Fast SCSI.
There is also a SCSI-2 definition of Wide-SCSI with a 32 bit
data bus. This allows up to 40 megabytes per second but is
very rarely used because it requires a large number of wires
(118 wires on two connectors). Thus Wide SCSI usually means
16 bit-wide SCSI.
(1995-04-21)
|
scsi
(jargon) | SCSI
n.
[Small Computer System Interface] A bus-independent standard for
system-level interfacing between a computer and intelligent devices.
Typically annotated in literature with ‘sexy’ (/sek'see/), ‘sissy’ (/sis´ee
/), and ‘scuzzy’ (/skuh'zee/) as pronunciation guides — the last being the
overwhelmingly predominant form, much to the dismay of the designers and
their marketing people. One can usually assume that a person who pronounces
it /S-C-S-I/ is clueless.
|
scsi voodoo
(jargon) | SCSI voodoo
/skuz'ee voo´doo/
[common among Mac users] SCSI interface hardware is notoriously fickle of
temperament. Often, the SCSI bus will fail to work unless the cable order
of devices is re-arranged, SCSI termination is added or removed (sometimes
double-termination or no termination will fix the problem), or particular
devices are given particular SCSI IDs. The skills needed to trick the
naturally skittish demons of SCSI into working are collectively known as
SCSI voodoo. Compare magic, deep magic, heavy wizardry, rain dance,
cargo cult programming, wave a dead chicken, voodoo programming.
While ordinary mortals frequently experience near-terminal frustration when
attempting to configure SCSI device chains, it is said that a true master
of this arcane art can (through rituals involving chicken blood, ground
rhino horn, hairs of a virgin, eye of newt, etc.) hook up your personal
computer with three scanners, a Zip drive, an IDE hard drive, a home
weather station, a Smith-Corona typewriter, and the neighbor's garage door.
|
ascsi
(vera) | ASCSI
Advanced Small Computer Systems Interface (SCSI)
|
cscsi
(vera) | CSCSI
Canadian Society for the Computational Studies of Intelligence
(org., Canada, AI)
|
iscsi
(vera) | ISCSI
Internet Small Computer Systems Interface (SCSI, SAN, IETF, RFC
3720/3721/3722), "iSCSI"
|
scsi
(vera) | SCSI
Small Computer Systems Interface (SCSI)
|
|