2.2.3Connecting the SCSI Peripherals

SCSI bus connections to the LSIU80ALVD inside your computer can be made with an unshielded 68-conductor Ultra SCSI PVC ribbon cable (see Figure 2.3). One side of this cable is marked with a colored stripe to indicate pin 1. Sometimes the connectors on this cable are keyed to ensure proper pin-1 connection.

All external SCSI bus connections to the LSIU80ALVD are made with high quality shielded 68-conductor cables (see Figure 2.3). The connectors on this cable are always keyed to ensure proper pin-1 connection.

Note: All the cables shown in Figure 2.3 are included in the

LSI Logic Adapter Board Kit for the LSIU80ALVD.

Table 2.1

SCSI Bus Widths and Speeds

 

 

 

 

 

 

 

SCSI Bus Speed

 

 

SCSI Bus

Maximum Data Rate,

STA Terms

Width, Bits

Mbytes/s

 

 

 

 

SCSI-1

 

8

5

 

 

 

 

Fast SCSI

 

8

10

 

 

 

Fast Wide SCSI

16

20

 

 

 

 

Ultra SCSI

 

8

20

 

 

 

Wide Ultra SCSI

16

40

 

 

 

 

Ultra2 SCSI

 

8

40

 

 

 

Wide Ultra2 SCSI

16

80

 

 

 

Note: Absence of the word “Wide” means an 8-bit bus width. It is

acceptable to use the word “Narrow” to avoid ambiguity.

 

 

 

 

You can connect up to eight SCSI, Fast SCSI, and Ultra SCSI devices on a SE Ultra SCSI bus only if they are evenly spaced on a 1.5-meter Ultra SCSI cable (0.19 m between devices).

Detailed Installation Procedure

2-7