Adaptec 29320A-R User Guide - Page 25

Introduction s On both SCSI buses (channels) the Adaptec SCSI Card is preset to SCSI ID 7 and should not be changed. This gives the card the highest priority on the SCSI bus. s Most internal SCSI hard disk drives come from the factory preset to SCSI ID 0. s If you have 8-bit (or Narrow) SCSI devices, they must use SCSI IDs 0, 1, 2, 3, 4, 5, or 6. SCSI ID 0 is recommended for the first SCSI hard disk drive. s If you are booting your computer from a SCSI hard disk drive connected to the Adaptec SCSI Card, the Boot SCSI ID setting in the SCSISelect utility must correspond to the SCSI ID of the device from which you are booting. By default, the Boot SCSI ID is set to 0. We recommend that you do not change this setting. s With the SCSISelect disk utility feature, you can confirm/view which SCSI ID is assigned to each device. See Chapter 3, Configuring the Adaptec SCSI Card with SCSISelect for more information. Terminating the SCSI Bus To ensure reliable communication on the SCSI bus, the ends of the SCSI bus must be properly terminated. This is accomplished when the device at the end of each cable, or the end of the cable itself, has a terminator installed (or enabled). Terminators must be removed, or termination must be disabled, on devices between the ends of each cable. Since the method for terminating a SCSI device can vary widely, refer to the device's documentation for instructions on how to enable or disable termination. Here are some general guidelines for termination: s Internal Ultra320/Ultra160 and Ultra2 SCSI LVD devices come from the factory with termination disabled and cannot be changed. Proper termination for these internal devices is provided by the built-in terminator at the end of the 68-pin internal LVD SCSI cable. 1-9