Parallel SCSI (formally,
SCSI Parallel Interface, or
SPI) is one of the interface implementations in the
SCSI family. In addition to being a
data bus, SPI is a
parallel electrical bus: There is one set of electrical connections stretching from one end of the SCSI bus to the other. A SCSI device attaches to the bus but does not interrupt it. Both ends of the bus must be terminated.