SCSI - General Information
| Ultra160 | Ultra320 | Ultra2 vs Ultra160 | Dual vs Single CHannel | SCSI ASICs |
SCSI is an abbreviation for "Small Computer System Interface". This I/O bus interface provides faster data transmission rates than that of IDE
("Integrated Drive Electronics") interface.
Many variations of SCSI interface are available to provide flexibility in todays various business applications. The following is a list of various interfaces used:
- Fast SCSI - Delivers a 10 MB/sec transfer rate with an 8-bit bus
- Fast Wide SCSI - Combined with a 16-bit bus, the data transfer rate is 20 MB/sec.
- SCSI-1 - This standard utilizes an 8-bit bus with a data transfer rate of 5 MB/sec.
- SCSI-2 - Basically the same as SCSI-1 but supports multiple devices and uses 50-pin connectors.
- SO-DIMM SCSI
- This "credit card" sized RAID card plugs into a specially designed small form factor PCI connector. This unique design gives high-density servers advance RAID data protection and performance without sacrificing a PCI slot making it ideal for a 1U environment.
- Ultra SCSI - Two times faster than Fast SCSI (8-bit bus with a data transfer rate of 20 MB/sec)
- Ultra Wide SCSI - Delivers data rate of 40 MB/sec using a 16-bit bus
- Ultra2 SCSI - Utilizes an 8-bit bus with data transfer rate of 40 MB/sec.
- Ultra2 Wide SCSI - 80 MB/sec data transfer rate using a 16-bit bus
- Ultra3 SCSI - loose term for SCSI interface standard that may include Fast-80, CRC, Domain Validation, QA, Packetized SCSI, or Double Transition Clocking.
- Ultra160 SCSI - 160 MB/sec data transfer rate
- Ultra320 SCSI
- Ultra320 SCSI is the seventh generation of SCSI I/O technology. Its dominant feature is its increased speed of 320 MBytes per second. Other features include; paced data transfer, a free running clock, a training pattern at the beginning of a transfer series, skew compensation, driver pre-compensation and/or optional receiver Adjustable Active Filter (AAF). Ultra320 SCSI devices all support packetized protocol and may support Quick Arbitration and Selection (QAS). Expander communications techniques have also been defined.
- Wide SCSI - Utilitzes a 16-bit bus with a data transfer rate of 10 MB/sec.