IBM PCI Dual Channel Ultra3 SCSI Adapter, Инструкция по установке и использованию

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Setting SCSI Addresses
Each SCSI device requires a different SCSI address. The address is a number from 6
through 0 for 8-bit devices, or from 6 through 0 and 15 through 8 for 16-bit devices. If
two SCSI devices have the same address, your system does not function correctly.
SCSI address 7 is reserved for the adapter, so additional SCSI devices can be set to
addresses 6 through 0 and 15 through 8.
Determining Current SCSI Addresses
Manufacturers use many different methods to set SCSI addresses, including jumpers,
dual inline package (DIP) switches, push buttons, or dials. If your SCSI device is new,
check the documentation that was shipped with the device to see if it specifies a default
SCSI address. If a default address is not specified, check how SCSI devices are set,
then check the device itself for the current SCSI address. Be sure to maintain a list of
all your SCSI addresses for future reference (your system unit documentation may
provide a table where you can record them).
Planning SCSI Addresses
No two SCSI devices (on the same SCSI bus channel) should have the same SCSI
address, and no device should use the address 7. Address 7 is reserved for the
adapter.
In subsystems that have drives shared between two ybesystems, each port of the
subsystem is connected to a different SCSI adapter. The second adapter’s SCSI
address must not conflict with that of any other device. It may be necessary to remove
a drive to provide an address for the second adapter.
Note: System or subsystem backplane services may require an address of their own.
This address is usually ID 15.
Changing SCSI Addresses
To change SCSI addresses, follow the instructions in the documentation provided with
each device.
Terminating the SCSI Devices and Adapter
Some SCSI devices have built-in terminators controlled by a DIP switch, jumper, or
push button. Other devices use terminators on the cable. Some devices require a
terminator be plugged into the device on a connector. After planning your installation,
supply the correct terminator to the SCSI device on the device end of the chain. The
adapter always terminates at one end of the chain. Refer to the device instructions to
determine how it is terminated. If necessary, purchase terminators when you buy
devices and cables.
For reliable SCSI operation, active terminators are required for all installations.
The basic rules of terminating SCSI buses are as follows:
v
Terminate the ends of the chain.
v
Do not terminate devices in the middle of the chain.
Appendix C. Connecting SCSI Devices to the Adapter
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