Alpha Microsystems AM-647 User manual

PDI-00649-00, A01
AM-647, 648 & 649
Digital Audio Tape (DAT)
High Capacity Tape Drives
Installation Instructions
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FIRST EDITION: August 1997
To re-order this document, request part number PDI-00649-00
FCC Notice
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC
Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a
commercial environment. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in
accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a
residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own
expense.
Canadian Department of Communications Compliance Statement
This equipment does not exceed Class A limits per radio noise emissions for digital apparatus set out in the Radio Interference
Regulations of the Canadian Department of Communications. Operation in a residential area may cause unacceptable interference
to radio and TV reception requiring the owner or operator to take whatever steps are necessary to correct the interference.
Avis de Conformité aux Normes du Ministère des Communications du Canada
Cet équipment ne deapsse pas les limits de Classe A d'émission de bruits radioélectriques pour les appareils numeriques tels que
prescrites par le Règlement sur le brouillage radioélectrique établi par le ministère des Communications du Canada. L'exploitation
faite en milleu résidential peut entrainer le brouillage des réceptions radio et tele, ce qui obligerait le propriétaire ou l'opératour à
pendre les dispositions nécessaires pour en éliminer les causes.
Battery Warning
CAUTION: Danger of explosion if battery is incorrectly replaced. Replace only with the same or equivalent type recommended by the
manufacturer. Discard used batteries according to the manufacturer's instructions.
ATTENTION: Il y a danger d'explosion s'il y a replacement incorrect de la batterie. Remplacer uniquement avec une batterie du
même type ou d'un type recommandé par le constructeur. Mettre au rébut les batteries usagées conformément aux instructions du
fabricant.
For AM-6000 systems, replace batteries with Panasonic or Ray-O-Vac BR1225 only. Use of another battery may present a risk of fire
or explosion. Replacement batteries may be ordered from your authorized Alpha Micro reseller.
Electrical Warning
This equipment contains components that can be damaged by static electricity. Follow all electronic discharge precautions when
handling the equipment. For example, touch the metal back panel of the CPU or peripheral chassis to dissipate any electrical charge
before touching the circuit boards or equipment within the chassis. After turning off power, before you open your computer chassis,
unplug the cord from the electrical outlet to guard against electrical shock.
SOFTWARE SECURITY DEVICE IDENTIFICATION NUMBER: _________________
The Alpha Micro Software Security Device (SSD) is a customized integrated circuit that personalizes the computer, providing identity
verification for it. Certain Alpha Micro and non-Alpha Micro software may require that your computer contain an SSD in order to run
software that has been customized to run only on your computer.
Please enter the identification of your SSD above. The SSD identification number should be on your computer ID label under "SSD
Serial No." (Another way of finding the number is to look at the SSD itself. The SSD is located in an integrated circuit location on the
CPU board; its identification number is printed on the SSD itself.) Software vendors may ask you for the SSD number if they are
customizing software to run only on your computer.
This document may contain references to products covered under the following U.S. Patent Number(s): 4,530,048
ALPHA MICROSYSTEMS
2722 Fairview Street
P. O. Box 25059
Santa Ana, CA 92704

PDI-00649-00, A01
Table of Contents
INTRODUCTION 1
PRODUCT DESCRIPTIONS 1
Common Characteristics 1
SCSI Bus Terminology 1
AM-647 (Archive) DAT Drive Characteristics 2
AM-648 (Exabyte) DAT Drive Characteristics 2
AM-649 (HP) DAT Drive Characteristics 2
Drive Mounting Kits 2
TOOLS REQUIRED 3
PREPARING THE DAT DRIVE FOR INSTALLATION 3
Jumpers and Switch Settings 3
SCSI BUS TERMINATION 9
Termination Resistor Pack Locations 9
External SCSI Bus Termination 10
Internal SCSI Bus Termination 12
Termination Power 12
DAT INSTALLATION—EAGLE AND AM-1600 DESKSIDE COMPUTERS 13
DAT INSTALLATION—RACK MOUNT AND PEDESTAL COMPUTERS 13
Front Bezel Removal and Modification 14
Building and Installing the DAT Drive Mounting Assembly 14
Power and Interface Cables 18
DAT INSTALLATION—AM-1400 AND AM-1600 DESKTOP COMPUTERS 19
DAT INSTALLATION—AM-990 COMPUTERS 21
SOFTWARE INFORMATION FOR DAT DRIVES 22
OPERATING SOFTWARE—MINIMUM FILE VERSIONS 23
COPYING THE GENERIC DEVICE DRIVER 24
MODIFYING THE SYSTEM INITIALIZATION COMMAND FILE 24
TESTING THE INITIALIZATION FILE 25
WARM BOOTING 26
RUNNING SELF TEST 29
AM-647 DAT DRIVE STATUS LEDS 29
AM-648 DAT DRIVE STATUS LEDS 30
AM-649 DAT DRIVE STATUS LEDS 31
USING YOUR DAT DRIVE 32
MAINTENANCE 35
TAPE FORMATS, USAGE, AND CAPACITIES 35
DDS, DDS-1, DDS-2, and Media Recognition 36
DAT Tape Identification 36
Tape Capacities 37
ADDITIONAL DOCUMENTATION 37

Page ii AM-64x DAT High Capacity Tape Drives
PDI-00649-00, A01
List of Figures
Figure 1 - AM-647 Configuration—3.5” Wide Model 4
Figure 2 - AM-647 Configuration—5.25” Wide Model 5
Figure 3 - AM-648 (Exabyte) Configuration 6
Figure 4 - AM-649-00 Configuration—HP Model C1536A 7
Figure 5 - AM-649-01 Configuration—HP Model C1533A/C1599A 8
Figure 6 - AM-649-00 and -01 Configuration Option Switches 9
Figure 7 - AM-648 (Exabyte) On-Board Terminators 10
Figure 8a - External SCSI Terminator - Narrow 11
Figure 8b - External SCSI Terminator - Wide 11
Figure 9 - Drive Mounting Assembly 15
Figure 10 - Plastic Mounting Base 16
Figure 11 - Metal Top Support Bracket 17
Figure 12 - Securing the Drive Assembly to the Front Bezel 18
Figure 13 - AM-1400/1600 Drive Mounting Bracket 19
Figure 14 - AM-1400/1600 Drive Mounting Assembly 20
Figure 15 - Peripheral Mounting Rail 21
Figure 16 - Attaching Mounting Rails to Peripheral 22
Figure 17 - DAT Warm Boot—CPU Boot Switch Settings 29
Figure 18 - AM-647 DAT Drive Faceplate 30
Figure 19 - AM-648 DAT Drive Faceplate 31
Figure 20 - AM-649 DAT Drive Faceplate 31
Figure 21 - Loading a DAT Tape Cartridge 33
Figure 22 - DAT Tape Cartridge Logos 36

AM-64x DAT High Capacity Tape Drives Page 1
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INTRODUCTION
This document describes the installation of the AM-647, AM-648, and AM-649 Digital Audio Tape
(DAT) SCSI High Capacity Tape Drives into an Alpha Micro computer system.
If you are installing a DAT drive into an external subsystem, use the installation instructions
shipped with the subsystem. If you are installing a DAT drive in a Series 90 computer,
installation instructions are included in the Series 90 SCSI tape drive controller documentation.
These instructions are written for an experienced Alpha Micro Service Technician. If you do not feel
comfortable performing the hardware and software procedures discussed below, contact your Alpha
Micro VAR or the Alpha Micro Technical Assistance Center for help.
PRODUCT DESCRIPTIONS
This manual covers several different DAT tape drives for use in various Alpha Micro computers. Cable
connections, software installation, and use are essentially the same for all DAT drives. However, each
DAT has certain unique operational characteristics.
Common Characteristics
• Can be mounted in any 5.25” configuration
• Must be attached to the system SCSI bus
• Use 4mm magnetic tape
• Use the same 647DVR.DVR software driver
SCSI Bus Terminology
Over the years, Alpha Micro computers have offered three different “SCSI” busses. We refer to them as
follows:
1. The bus in AM-2000/3000 and other older computers, which supports up to four SCSI devices,
is the “SASI bus.”
2. The SCSI bus in Eagles, Roadrunners, the AM-4000, and newer computers, which requires a
SCSI dispatcher and supports up to seven devices, is the “SCSI-2 bus.”
3. The enhanced Wide SCSI-2 bus introduced on the AM-6000 and Roadrunner 060 is the “Wide
SCSI-2 bus.” This bus supports up to 15 devices.

Page 2 AM-64x DAT High Capacity Tape Drives
PDI-00649-00, A01
AM-647 (Archive) DAT Drive Characteristics
• Two models: a 3.5” half-height drive, and a 5.25” half-height drive.
• Both drives have the same operational characteristics.
• Has a data capacity of approximately 2 gigabytes using 90 meter tapes
• Can be used on a SASI or SCSI-2 bus, including Wide SCSI-2 with an appropriate adapter
• CANNOT read/write compressed data tapes
AM-648 (Exabyte) DAT Drive Characteristics
• Has a data capacity of approximately 2 gigabytes in standard DDS (non-compressed) mode, and
approximately 4 gigabytes in DDS-DC compressed mode with a 90 meter tape
• Can be used on a SCSI-2 bus only, including Wide SCSI-2 with an appropriate adapter
• Can be forced into compressed or non-compressed mode using the AMOS TMODE command
AM-649 (HP) DAT Drive Characteristics
• There are two models of the AM-649 DAT drive:
• The AM-649-00 4 gigabyte drive (HP model C1536A) has a data capacity of
approximately 2 gigabytes in DDS (non-compressed) mode, and approximately 4
gigabytes in DDS-DC compressed mode with a 90 meter tape.
• The AM-649-01 8-gigabyte drive (HP model C1533A or C1599A) has the same data
capacities as the AM-649-00 using DDS/DDS-1 tape, with additional DDS-2 capabilities
yielding approximately 4 gigabytes of storage in native DDS-2 mode and 8-gigabytes in
DDS-2-DC compressed mode, when used with 120 meter DDS-2 tapes. In DDS-2 mode,
file access and data transfer rates are significantly faster than DDS/DDS-1 modes.
• Can be used on a SCSI-2 bus only, including Wide SCSI-2 with an appropriate adapter
• Can be forced into compressed or non-compressed mode using the AMOS TMODE command
See the "DAT Drive Compatibility" section of this manual and the TMODE reference sheet in
the Alpha Micro System Commands Reference Manual for more details on switching between
compressed and non-compressed data modes.
Drive Mounting Kits
In addition to the DAT tape drive, some installations require a drive mounting kit. Each mounting kit
includes the hardware to install a DAT drive in a particular type of computer. The following chart shows
the mounting kits needed for different Alpha Micro computers:

AM-64x DAT High Capacity Tape Drives Page 3
PDI-00649-00, A01
System Type Mounting Kit
VME Rack Mount PDB-00625-60
VME Pedestal PDB-00625-61
AM-2000M/AM-3000M * PDB-00625-61
AM-1400/AM-1600 Desktop ** PDB-00647-50
AM-990 VME and SBC Not required
Eagle Deskside Not required
AM-1600 Deskside Not required
* With Roadrunner or AM-540 upgrade (AM-649-01 not compatible with AM-540)
** For AM-647 DAT drives only—other models not compatible
Make sure you have the correct mounting kit before you begin. The DAT drive has the same
environmental specifications as your computer.
TOOLS REQUIRED
For most installations, the only tools you need to install the DAT drive are a #2 Phillips-head
screwdriver and a pair of needle-nose pliers.
PREPARING THE DAT DRIVE FOR INSTALLATION
First, you need to select the SCSI ID of the DAT drive by setting the proper switches on the back of the
drive. If your computer uses a SCSI bus, you have seven SCSI IDs to choose from (0 through 6). The
SASI bus supports only SCSI IDs 0 through 3. Don't worry if you have a gap in your device addressing;
AMOS doesn't require that each device be defined in sequence.
Except for systems with a CMOS configuration menu, such as the Eagle 550 and Roadrunner
060, if you want to be able to warm boot from your DAT drive, you must set it to a higher SCSI
ID than any other tape device on the bus.
While the Wide SCSI-2 bus supports IDs up to 15, all Alpha Micro DAT drives are narrow SCSI
devices. You cannot set one to an ID higher than 6, even if it is attached to the Wide SCSI-2 bus
with an adapter.
Jumpers and Switch Settings
Refer to the following illustrations for configuration and jumper locations for your DAT drive.
There are two physically different types of AM-647 DAT drives: a 3.5” wide, half-height drive in
a 5.25” mounting bracket, and a full 5.25” wide, half-height drive. Although their physical sizes
and the locations of jumpers and switches are different, the same configuration rules apply to
both.

Page 4 AM-64x DAT High Capacity Tape Drives
PDI-00649-00, A01
1
RD2
RD1
SW1
TERMINATORS
SW1
O F F
1
2
3
4 5 6 7
8
DAT DRIVE
MOUNTING HOLES
O F F
1
2
3
O F F
1
2
3
NO JUMPERS INSTALLED AT THIS LOCATION
O F F
1
2
3
SCSI ID
0
1
2
3
PARITY IS ENABLED AND DISABLED USING
SWITCH #5. FOR AMOS BASED COMPUTERS,
SWITCH #5 WLLALWAYS BE SET TO THE "OFF"
OR DISABLED POSITION. SERIES 90 PRODUCTS
WILL SET SWITCH #5 TO THE "ON" OR ENABLED
POSITION.
JP4
JP4 "IN" = DRIVE SUPPLIES TERMINATION
POWER TO THE SCSI BUS.
JP4 "OUT" = DRIVE DOES NOT SUPPLY
TERMINATION POWER TO THE
SCSI BUS.
SWIITCH #4 IN THE "OFF" POSITION = SCSI-1
SWITCH #4 IN THE "ON" POSITION = SCSI-2
O F F
1
2
3
O F F
1
2
3
O F F
1
2
3
4
5
6
Leave switches 6, 7, and 8
set as shown in the illustration.
Figure 1 - AM-647 Configuration—3.5” Wide Model

AM-64x DAT High Capacity Tape Drives Page 5
PDI-00649-00, A01
SW1
O F F
1
2
3
4 5 6 7
8
O F F
1
2
3
O F F
1
2
3
O F F
1
2
3
SCSI ID
0
1
2
3
PARITY IS ENABLED AND DISABLED USING
SWITCH #5. FOR AMOS BASED COMPUTERS,
SWITCH #5 WLLALWAYS BE SET TO THE "OFF"
OR DISABLED POSITION. SERIES 90 PRODUCTS
WILL SET SWITCH #5 TO THE "ON" OR ENABLED
POSITION.
SWIITCH #4 IN THE "OFF" POSITION = SCSI-1
SWITCH #4 IN THE "ON" POSITION = SCSI-2
O F F
1
2
3
O F F
1
2
3
O F F
1
2
3
4
5
6
Leave switches 6, 7, and 8
set as shown in the illustration.
1 2 3 4 5 6 7 8
O F F
TERMINATORS
TERMINATION POWER JUMPER
0UT = TERMINATION POWER DISABLED
IN = TERMINATION POWER ENABLED
PIN-1
Figure 2 - AM-647 Configuration—5.25” Wide Model

Page 6 AM-64x DAT High Capacity Tape Drives
PDI-00649-00, A01
SCSI ID #0 SCSI ID #1 SCSI ID #2 SCSI ID #3
SCSI ID #4 SCSI ID #5 SCSI ID #6
The two outside pins (shown in gray) are used to
select SCSI-1 or SCSI-2. With the jumper removed,
the drive is configured for SCSI-2; with the jumper
installed the drive is configured for SCSI-1. For all
Alpha Micro configurations, the drive must be
configured for SCSI-2 operation.
DC POWER
PIN-1
KEYED
CONNECTOR
Figure 3 - AM-648 (Exabyte) Configuration

AM-64x DAT High Capacity Tape Drives Page 7
PDI-00649-00, A01
The AM-649-00 4 gigabyte DAT drive (HP model C1536A) has no provision to disable its term
power! Therefore, this drive should only be installed in the main system chassis and connected
to the same power supply as the rest of the internal SCSI peripheral devices. This drive should
never be connected to a different/subsystem power supply, as erratic system operation may
result!
SCSI 2 1 0 NC
2 1 0 NC
SCSI I.D. 0
2 1 0 NC
SCSI I.D. 1
2 1 0 NC
SCSI I.D. 2
2 1 0 NC
SCSI I.D. 4
2 1 0 NC
SCSI I.D. 5
2 1 0 NC
SCSI I.D. 6
2 1 0 NC
SCSI I.D. 3
SCSI CONNECTOR DC POWERPIN-1
SCSI ADDRESS JUMPERS
HP 4mm DAT Drive - Model C1536A (4 GB)
MC1277
Figure 4 - AM-649-00 Configuration—HP Model C1536A

Page 8 AM-64x DAT High Capacity Tape Drives
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The AM-649-01 may be labeled as either Model C1533A or C1599A. From an AMOS standpoint,
these models are identical. AMOS software which returns the model number displays C1533A for
either drive.
When configuring the AM-649-01 drive, be sure to remove the TERM POWER jumper located next to
the SCSI ID jumpers.
SCSI 2
SCSI CONNECTOR DC POWERPIN-1
SCSI ADDRESS JUMPERS
SCSI 1 SCSI 0 NC TERM PWR
SCSI I.D. 3
SCSI 2 SCSI 1 SCSI 0 NC TERM PWR
SCSI I.D. 2
SCSI 2 SCSI 1 SCSI 0 NC TERM PWR
SCSI I.D. 1
SCSI 2 SCSI 1 SCSI 0 NC TERM PWR
SCSI I.D. 0
SCSI 2 SCSI 1 SCSI 0 NC TERM PWR
SCSI I.D. 4
SCSI 2 SCSI 1 SCSI 0 NC TERM PWR
SCSI I.D. 5
SCSI 2 SCSI 1 SCSI 0 NC TERM PWR
SCSI I.D. 6
SCSI 2 SCSI 1 SCSI 0 NC TERM PWR
HP 4mm DAT Drive - Model C1533A/C1599A (8 GB)
Figure 5 - AM-649-01 Configuration—HP Model C1533A/C1599A
The AM-649-00 and -01 each have a series of eight option switches located on the bottom of the drive.
These switches control compression modes, the Media Recognition System, and compatibility issues
with other computer manufacturers. Refer to Figure 6 for settings and details.

AM-64x DAT High Capacity Tape Drives Page 9
PDI-00649-00, A01
ON
12345678
HP 4mm DAT Option Switches
AMOS Default Configuration
SWITCH 1 SWITCH 2 MEANING
---------------------------------------------------------------------------------------------------------------
On On Compression enabled at power-on, with host control
On Off Compression enabled at power-on, no host control
Off On Compression disabled at power-on, the host is allowed to
control compression
Off Off Compression disabled at power-on, no host control
SWITCH 3 MEANING
---------------------------------------------------------------------------------------------------------------
On The Media Recognition System is disabled. All DDS tapes will be treated
the same, whether they possess the Media Recognition Stripes or not.
Off The Media Recognition System is active. This is the default. Non-Media
Recognition System tapes are treated as if they are write-protected.
SWITCHES 4 - 8
---------------------------------------------------------------------------------------------------------------
Switches 4-8 are used to specify drive connectivity and functionality according to host or
customer requirements. The majority of functions controlled by these switches concern
UNIX software and operational compatibility with SUN, IBM, and DEC computer systems.
The AMOS default setting is switches 4-8 set to on .
Figure 6 - AM-649-00 and -01 Configuration Option Switches
SCSI BUS TERMINATION
To function properly, the SCSI bus on your computer must be terminated at each end of the cable. The
SCSI controller terminates one end of the bus; the opposite end of the bus can be terminated in one of
two ways: 1) using the preferred method—an external terminator, or 2) installing on-board terminators in
the peripheral that's at the other end of the SCSI cable. You should use method 2 only if, for some
reason, you cannot use an external terminator in your installation.
Termination Resistor Pack Locations
Under most conditions, if the new peripheral device has on-board terminators they should be removed!
The terminators should be left installed only if you are not using an external terminator, and the drive
you're installing is physically connected as the last device on the SCSI cable.
AM-649-00 and -01 drives (HP models C1536A, C1533A, and C1599A) DO NOT HAVE ON-
BOARD TERMINATORS. If these drives are used without an external terminator, they cannot
be the last device on the SCSI cable. Another device must be attached as the last device on the
SCSI cable and configured to provide SCSI bus termination!

Page 10 AM-64x DAT High Capacity Tape Drives
PDI-00649-00, A01
Figures 1 and 2 show the location of the AM-647 on-board terminators. Refer to Figure 7 for the location
of the AM-648 on-board terminators.
AM-648 ON-BOARD TERMINATORS
Figure 7 - AM-648 (Exabyte) On-Board Terminators
External SCSI Bus Termination
The preferred way to terminate the SCSI bus in an AMOS computer is to install an external terminator.
In April of 1993, the external SCSI bus terminator became standard on all AMOS computers. Using an
external terminator makes it easier to install an add-on subsystem (like a portable CD-ROM drive),
eliminating the need to remove terminators from a SCSI device inside the computer.
As computer performance increases, the SCSI bus becomes more sensitive to termination issues. Newer
AMOS computers, such as the AM-6000, require active termination of the SCSI bus. Check your
computer Owner’s Manual to make sure you are terminating the SCSI bus properly.
External terminators are available from Alpha Micro under part numbers PRA-00222-00 (narrow passive
terminator), PRA-00222-21 (narrow active terminator), and PRA-00222-20 (wide active terminator).
To use the external terminator, you need to insure none of the SCSI devices inside the computer are
terminated. You also need to follow the guidelines in the section on providing termination power to the
SCSI bus.

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10- and 21-slot rack mount VME computers have no external SCSI connector. To install an external
terminator, you need a special adapter cable, DWB-10200-01. The connector on this cable is compatible
with the external terminator and also allows you to easily attach a portable CD-ROM drive or other SCSI
device.
The figures below show both narrow and wide SCSI terminators:
SCSI
BAIL LOCKS
Figure 8a - External SCSI Terminator - Narrow
PRA-00222-20
EXTERNAL SCSI BUS
TERMINATOR
SCSI CONNECTOR
ON BACK PANEL
Figure 8b - External SCSI Terminator - Wide

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Figures 8a and 8b show two different types of external SCSI connectors:
1. Figure 8a shows an external narrow SCSI connector and bail locks for holding the terminator in
place. This configuration is used on most of Alpha Micro's currently available product. The
terminator is installed by plugging it onto the connector, then latching the bail locks into the
notches on the sides of terminator.
2. Figure 8b shows an external wide SCSI connector. The terminator is held in place by thumb
screws.
Internal SCSI Bus Termination
If you are not using external SCSI termination, you may terminate the SCSI bus by enabling the
termination resistors on the last SCSI device—the one farthest away from the SCSI controller. For best
termination and most reliable SCSI performance in any configuration, this device should be at the actual
physical end of the SCSI cable. If the SCSI cable extends beyond the device which provides
termination, even if there are no more devices attached, termination will not be as reliable as it would be
if the actual end of the cable was terminated.
Be sure that only the last SCSI device has its on-board termination enabled. If more than one
device on the SCSI bus has its termination enabled, your system will probably perform
erratically! This is true whether the last device is in the computer chassis or in a subsystem
chassis.
Termination Power
In order to properly control SCSI bus termination, a termination power source must be provided; this is
especially important when using an external terminator.
Why is Termination Power so important when using an external terminator?
Any terminator must have a power source. Because an external terminator does not have its own source
of power, it must get its termination power from the SCSI bus. If termination power is not available on
the bus, the external terminator cannot do its job, which means your SCSI bus will not be terminated
properly. This may result in a computer that won't boot, or that "hangs" frequently. As mentioned above,
the higher performance SCSI-2 and Wide SCSI-2 busses are more prone to exhibit problems when
improperly terminated than was the older SASI bus.
The termination power source can be configured in one of the following ways, depending on your
system hardware:
• In AMOS computers using the SASI bus, one of the internally mounted peripherals must supply
termination power to the SCSI bus.
• AMOS computers using the SCSI-2 or Wide SCSI-2 bus should be configured to supply
termination power via the host controller. When SCSI bus termination power is supplied by the
host controller, there should not be any SCSI peripherals supplying termination power to the bus.

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• SCSI subsystems attached to the main system should not have any additional devices supplying
termination power to the SCSI bus. Termination power for the bus should be supplied by one
source only!
The AM-649-01 (8GB) DAT drive has a jumper on the rear to disable term power, but the AM-
649-00 (4GB) DAT drive has its term power permanently enabled! Although Alpha Micro
always recommends only one source of termination power to the bus, this particular exception
has thus far proven not to be a problem—as long as the drive is installed in the main system and
connected to the same DC power supply as the other SCSI devices on the bus. However,
performance of this drive may become unstable if it's mounted in an external subsystem chassis
and/or connected to a DC power supply other than the main system supply!
The SCSI host controllers on AM-137, AM-190, and AM-540 boards are permanently configured
to supply termination power to the SCSI bus. On Roadrunner boards, the termination power
feature can be enabled or disabled by setting a jumper. As of July 26th, 1994, Alpha Micro began
configuring all Roadrunner boards with termination power enabled. See the Roadrunner
installation instructions for information on how to configure the termination power jumper.
For information on how to configure terminator power on SCSI hard disk and magnetic tape peripherals,
see the following documents:
• Each SCSI disk drive shipped by Alpha Micro has a one page notice with jumper configuration
information, including instructions on how to configure termination power.
• AM-62X SCSI 1/4" Streaming Tape Drive Installation Instructions, PDI-00625-00, revision A07
or later.
DAT INSTALLATION—EAGLE AND AM-1600 DESKSIDE COMPUTERS
The owner's manuals for Eagle and AM-1600 deskside computers contain their own sets of instructions
for installing SCSI peripherals. However, you will still need to follow all the instructions in this
document dealing with software configuration and actual use of your DAT tape drive.
DAT INSTALLATION—RACK MOUNT AND PEDESTAL COMPUTERS
The following sections describe how to install the DAT drive into AMOS computers using both rack
mount and pedestal enclosures. The basic installation procedure is the same for both pedestal and rack
mount computers:
• Remove your front bezel.
• Create a cutout in your bezel to support the DAT drive.
• Build the DAT drive mounting assembly.
• Install the DAT drive mounting assembly in your computer.
• Attach the SCSI interface and power cables.

Page 14 AM-64x DAT High Capacity Tape Drives
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Front Bezel Removal and Modification
Your DAT drive product installation kit includes instructions describing how to modify your front bezel.
The modification requires you to make a half-height 5.25” cutout if you are installing a DAT drive only,
or a full-height 5.25” cutout if you are installing a DAT drive along with a new (or existing) floppy or
streaming tape drive.
1. Follow the instructions in your computer Owner's Manual for removing the top cover.
2. Unplug the ribbon cable that links the display panel on the computer's front bezel to your CPU
board.
3. Remove the Phillips-head screws holding the front bezel to the computer's chassis.
4. Follow the bezel modification instructions included with your installation kit, then reinstall the
bezel on your computer.
5. Don't forget to plug the display panel cable back into your CPU board.
Building and Installing the DAT Drive Mounting Assembly
The DAT drive mounting assembly is the same for both pedestal and rack mount computers. The
assembly consists of three pieces; one plastic mounting base, one DAT drive, and one metal support
bracket. The following steps describe how to put the assembly together:
1. Set the drive on top of the plastic mounting base with its status LEDs nearest the plastic
mounting base. This insures the drive is in the proper position for both pedestal and rack mount
computers. Also, pin-1 on the DAT drive's SCSI connector has the same orientation as the other
SCSI devices in your computer.

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PLASTIC MOUNTING BASE
DWF-20218-00
DISKETTE DRIVE
METAL SUPPORT BRACKET
DWF-20260-00
DRIVE ACTIVITY LED
SCSI DAT
TAPE DRIVE
*
DRIVE ACTIVITY LEDs
* Faceplate varies per DAT model.
Figure 9 - Drive Mounting Assembly
2. The DAT drive has several mounting screw-holes on its side rails, which align with
corresponding holes in the plastic mounting base. Align the screw holes on the drive with the
proper holes (marked as A in Figure 10) in the plastic mounting base. Make sure the drive's front
panel is pointed in the direction indicated by the arrow in Figure 10.
3. Install the two screws (included in the mounting kit) that hold the plastic mounting base to the
drive. If you are installing a diskette drive or a 1/4" streaming tape drive along with your DAT
drive, mount it next to the DAT drive, as shown in Figure 9.
4. Set the drive assembly into its mounting position inside the chassis.

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DWF-20218-00
MAKE SURE THE DRIVE'S
FRONT PANEL IS POINTED IN THE
DIRECTION INDICATED BY THEARROW
A
B
C
C
B
A
SCSI DAT OR STREAMING TAPE DRIVE, or
ANY 5-1/4" HALF-HEIGHT SCSI HARD DISK DRIVE
AM-645 FULL-HEIGHT 8MM MAGNETIC TAPE DRIVE, or
ANY 5-1/4" FULL-HEIGHT SCSI HARD DISK DRIVE
ANY 5-1/4" HALF-HEIGHT FLOPPY DISKETTE DRIVE, or
ANY 5-1/4" HALF-HEIGHT SCSI HARD DISK DRIVE
Figure 10 - Plastic Mounting Base
6. Set the metal support bracket on top of the drive assembly as shown in Figure 9. Position the
bracket so the mounting hole (see Figure 11) aligns with the screw hole on the side (top) of the
DAT drive and the screw hole in the metal support bracket aligns with the screw hole in the
front bezel.