Fairlight Merlin - Configuring Disk Drives; External Hard Disk Drives; Narrow Based Disk Drives; Wide Based Disk Drives

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SECTION 5 - CONFIGURING DISK DRIVES
5.1 EXTERNAL HARD DISK DRIVES
An additional SCSI controller can be added to the system and fitted in one of three PCI
slots on the PXY Main Processor Board. With the controller physically installed an additional 7
SCSI devices can be connected to the system.
5.1.1 WIDE BASED DISK DRIVES
The Ultra Wide single ended SCSI specification is used within the internal and external SCSI
busses. This allows for ultra fast transfers speeds from a disk drive up to 40 megabytes a
second.
The SCSI controller comes configured with a single ended 68 Pin configuration connector.
Only a Fairlight supplied SCSI Controller can be installed and configured with the Engine.
When using narrow based disk drives along the SCSI buss the Engine must be configured
for Narrow use only.
All cabling to SCSI devices must be kept as short as possible. The maximum length for the
entire buss must not exceed more than 1.5 meters. It is highly recommended that drive
enclosures with an active backplane be used to reduce cable lengths.
Some disks have SCSI terminating resistors in place and these should be checked and
resistors removed when extra disks are being added to the system.
The last disk drive at the end of the chain must be terminated using an active
terminator.Lower transfer rates and SCSI errors will result if the buss is not correctly
terminated.
SCSI I.D.'s can be 0 through to 6. SCSI I.D. 7 is reserved for the SCSI controller.
5.1.2 NARROW BASED DISK DRIVES
Narrow Based SCSI Disk Drives may be attached to the buss but must always be the last in
the chain after any Wide disks are connected.
A quality 68 pin to 50 pin Adaptor must be used when connecting from the SCSI buss to a
narrow disk drive.
The end of the Buss must be terminated using an active SCSI terminator plugged into the
last drive in the chain.