Roland VS-890 - Manual (Page 4)

About SCSI
SCSI stands for Small Computer System Interface. It is a
data transfer standard that allows large amounts of data to
be sent and received. The VS-890 comes prepared with a
SCSI connectors allowing you to connect external SCSI
devices such as hard disks and Zip drives. This section
describes the procedures and precautions taken when using
these devices.
Disk drives are precision devices. If they are connected or
used incorrectly, not only may they fail to operate correctly,
but the data on the disk can be lost or, in the worst case, the
disk drive itself may be damaged. Please be sure to read the
manual for your disk drive.
A disk drive being used for the first time with the VS-890
must be initialized by the VS-890 (Owner's Manual p. 134).
When a disk drive is initialized, all data on that disk drive is
lost. Before using a disk drive that has been used by another
device, make sure that it is all right to erase the data.
About Connections
Up to 7 disk drives can be connected to the SCSI connector of
the VS-890. Use SCSI cable to connect the disk drives,
connecting as shown below. SCSI connectors are not
distinguished by input and output ends, so you may attach
either end of the cable to the devices. Devices connected in
this fashion are referred to as a
SCSI chain or daisy chain.
VS-B90 Disk Drivel
(Zip Drive, etc)
Disk DriveZ
(Zip Drive, etc)
Disk Drive?
(CD-RW Drive, etc)
The VS-890 features a DB-25 type connector (female).
After checking your disk drive to see what kind of SCSI
connector it uses, connect it with the appropriate cable.
Keep SCSI cables as short as possible, and use only
cables which have an impedance that is compatible with
the SCSI standard (llOQ + /-10%), and that are
completely shield.
Do not allow the total length of all SCSI cables
connecting the chain of disk drives to exceed 6.5 meters.
Do not connect or disconnect SCSI cables when the
power of any device is turned on.
About Terminators
To protect against return noise, the device at each end of a
SCSI chain must have a terminating resistance. This is
referred to as a terminator. Since the VS-890 is one end of the
SCSI chaia its internal terminator is normally in effect.
Connect a terminator only to the last externa! drive in the
chain. There are two types of terminators, those that can be
switched on and off (internal) and those that are attached
using SCSI connections (externally attached). Select the
method appropriate for the disk drive you are using.
• Your disk drive may feature a terminator switch that is
normally left in the "On" position (i.e., the terminator is
usually in effect). Use this type of device as the last piece
in a daisy chain.
• Do not use double terminators. For example, don't attach
an externa! terminator to a disk drive that already has
and internal terminator.
Active Terminators
If you are using an external terminator, we recommend that
you make it an active terminator. In this case, if you are using
a disk drive that allows you to turn the power to the
terminator on and off, be sure to turn this power on. For
details on attaching an active terminator, refer to the owner's
manual ftrr your disk drive.
Active Terminator (p. 12), Terminator Power (p. 13)
About SCSI ID Numbers
Each disk drive is distinguished by its SCSI ID number (0-7).
ITiis means that when two or more disk drives are connected,
you must make settings so that the SCSI ID numbers of the
disk drives do not conflict (coincide). If the SCSI ID numbers
conflict, the VS-890 will not be able to correctly recognize the
disk drives.
With the factory settings, the VS-890 is set to SCSI ID number
7. Set the disk drives you are connected to ID numbers other
than 7.