LSI U160 Table, SCSI Bus Lengths

pc 10.25 pc 11.25 pc 38

34.5 pc

You can connect up to four devices if they are evenly spaced on a

3-meter Ultra SCSI cable (0.75 m between devices). Your SE SCSI bus should not exceed 3 meters (total internal and external cable lengths), even with fewer than four devices.

For LVD applications, you can connect up to 16 devices including the host adapter if they are evenly spaced on a 12-meter Ultra SCSI cable (0.19 m minimum between devices). A list of the maximum bus length and the maximum number of devices, for various SCSI definitions, is provided in Table 2.2.

	Table 2.2	SCSI Bus Lengths
			Maximum Bus Length, Meters1
						Maximum #
			SE	Differential	LVD	of Devices
	SCSI-1		6	25	12	8
	Fast SCSI		3	25	12	8
pc	Fast Wide SCSI		3	25	12	16
	Ultra SCSI		1.52	25	12	8
	Ultra SCSI		32	–	–	4
	Wide Ultra SCSI		–	25	12	16
	Wide Ultra SCSI		1.5	–	–	8
	Wide Ultra SCSI		3	–	–	4
	Ultra2 SCSI		Note3	Note3	12	8
	Wide Ultra2 SCSI		Note3	Note3	12	16
	Ultra160 SCSI		Note3	Note3	12	16

1.This parameter may be exceeded in point-to-point and engineered applications.

2.Additional spacing rules apply.

3.SE and high power differential are not defined at Ultra2 or Ultra160 speeds.

2-8 Installing the LSIU160