Quantum sdlt 220 Guía Del Usuario
81-85002-01
March 2004
6-1
CHAPTER 6
SCSI Description
This chapter covers the following topics:
•
introduces the SCSI specification.
•
lists the SCSI-2 commands implemented by
SDLT 220/320.
•
lists the SCSI-3 commands implemented by
SDLT 220/320.
•
defines the meaning of data parity checking.
•
defines the meaning of SCSI signal values and SCSI IDs.
•
defines SCSI signals and provides bus timing values.
6.1
SCSI Overview
The Small Computer System Interface (SCSI) is a specification for a peripheral
bus and command set that is an ANSI standard. The standard defines an I/O wide
SCSI bus that supports up to 16 devices (15 SCSI devices and one host adapter).
bus and command set that is an ANSI standard. The standard defines an I/O wide
SCSI bus that supports up to 16 devices (15 SCSI devices and one host adapter).
ANSI defines three primary objectives for SCSI-2:
1.
To provide host computers with device-independence within a class of
devices.
devices.
2.
To be backward-compatible with SCSI-1 devices that support bus parity and
that meet conformance level 2 of SCSI-1.
that meet conformance level 2 of SCSI-1.
3.
To move device-dependent intelligence to the SCSI-2 devices.