Black Box IC540A User manual

CUSTOMER
SUPPORT
INFORMATION
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FREE technical support, 24 hours a day, 7 days a week: Call 724-746-5500 or fax [phone]
Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]
AUGUST 2000
IC540A
Ultra 2 SCSI LVD Expander
Ultra2 SCSI LVD
Multimode Extender

1
FCC/IC STATEMENTS
FEDERAL COMMUNICATIONS COMMISSION AND INDUSTRY CANADA
RADIO-FREQUENCY INTERFERENCE STATEMENTS
Class B Digital Device. This equipment has been tested and found to comply with
the limits for a Class B computing device pursuant to Part 15 of the FCC Rules.
These limits are designed to provide reasonable protection against harmful
interference in a residential installation. However, there is no guarantee that
interference will not occur in a particular installation. This equipment generates,
uses, and can radiate radio frequency energy, and, if not installed and used in
accordance with the instructions, may cause harmful interference to radio
communications. If this equipment does cause harmful interference to radio or
telephone reception, which can be determined by turning the equipment off and
on, the user is encouraged to try to correct the interference by one of the following
measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which
the receiver is connected.
• Consult an experienced radio/TV technician for help.
Caution:
Changes or modifications not expressly approved by the party
responsible for compliance could void the user’s authority to operate
the equipment.
This digital apparatus does not exceed the Class B limits for radio noise emission from digital
apparatus set out in the Radio Interference Regulation of Industry Canada.
Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les limites
applicables aux appareils numériques de la classe B prescrites dans le Règlement sur le
brouillage radioélectrique publié par Industrie Canada.

2
ULTRA2 SCSI LVD EXPANDER
NORMAS OFICIALES MEXICANAS (NOM)
ELECTRICAL SAFETY STATEMENT
INSTRUCCIONES DE SEGURIDAD
1. Todas las instrucciones de seguridad y operación deberán ser leídas antes de
que el aparato eléctrico sea operado.
2. Las instrucciones de seguridad y operación deberán ser guardadas para
referencia futura.
3. Todas las advertencias en el aparato eléctrico y en sus instrucciones de
operación deben ser respetadas.
4. Todas las instrucciones de operación y uso deben ser seguidas.
5. El aparato eléctrico no deberá ser usado cerca del agua—por ejemplo, cerca
de la tina de baño, lavabo, sótano mojado o cerca de una alberca, etc.
6. El aparato eléctrico debe ser usado únicamente con carritos o pedestales que
sean recomendados por el fabricante.
7. El aparato eléctrico debe ser montado a la pared o al techo sólo como sea
recomendado por el fabricante.
8. Servicio—El usuario no debe intentar dar servicio al equipo eléctrico más allá
a lo descrito en las instrucciones de operación. Todo otro servicio deberá ser
referido a personal de servicio calificado.
9. El aparato eléctrico debe ser situado de tal manera que su posición no
interfiera su uso. La colocación del aparato eléctrico sobre una cama, sofá,
alfombra o superficie similar puede bloquea la ventilación, no se debe colocar
en libreros o gabinetes que impidan el flujo de aire por los orificios de
ventilación.
10. El equipo eléctrico deber ser situado fuera del alcance de fuentes de calor
como radiadores, registros de calor, estufas u otros aparatos (incluyendo
amplificadores) que producen calor.
11. El aparato eléctrico deberá ser connectado a una fuente de poder sólo del
tipo descrito en el instructivo de operación, o como se indique en el aparato.

3
NOM STATEMENT
12. Precaución debe ser tomada de tal manera que la tierra fisica y la polarización
del equipo no sea eliminada.
13. Los cables de la fuente de poder deben ser guiados de tal manera que no
sean pisados ni pellizcados por objetos colocados sobre o contra ellos,
poniendo particular atención a los contactos y receptáculos donde salen del
aparato.
14. El equipo eléctrico debe ser limpiado únicamente de acuerdo a las
recomendaciones del fabricante.
15. En caso de existir, una antena externa deberá ser localizada lejos de las lineas
de energia.
16. El cable de corriente deberá ser desconectado del cuando el equipo no sea
usado por un largo periodo de tiempo.
17. Cuidado debe ser tomado de tal manera que objectos liquidos no sean
derramados sobre la cubierta u orificios de ventilación.
18. Servicio por personal calificado deberá ser provisto cuando:
A: El cable de poder o el contacto ha sido dañado; u
B: Objectos han caído o líquido ha sido derramado dentro del aparato; o
C: El aparato ha sido expuesto a la lluvia; o
D: El aparato parece no operar normalmente o muestra un cambio en su
desempeño; o
E: El aparato ha sido tirado o su cubierta ha sido dañada.

4
ULTRA2 SCSI LVD EXPANDER
Contents
Chapter Page
1. Specifications ............................................................................................. 5
2. Introduction ............................................................................................... 6
2.1 Overview .............................................................................................. 6
2.2 Features ............................................................................................... 8
2.3 The Complete Package ....................................................................... 8
3. Configuration and Internal LEDs ............................................................. 9
3.1 Opening the Expander ....................................................................... 9
3.2 Configuring Termination ................................................................. 11
3.3 Observing the Internal LEDs ........................................................... 14
4. Installation ................................................................................................ 15
4.1 Connecting the SCSI-Bus Cables ..................................................... 15
4.2 Connecting AC Power and Observing the External LEDs ............. 16
5. Applications .............................................................................................. 17
5.1 Applications That Will Work ............................................................ 17
5.2 Applications That Won’t Work ........................................................ 19
6. Troubleshooting ...................................................................................... 20
6.1 Calling Black Box .............................................................................. 20
6.2 Shipping and Packaging ................................................................... 20
Appendix A: Port Pinouts ............................................................................... 21
A.1 Low-Voltage Differential (LVD) Pinout ........................................... 21
A.2 Single-Ended (SE) Pinout ................................................................. 23
Appendix B: Block Diagram .......................................................................... 25

5
CHAPTER 1: Specifications
1. Specifications
Compliance — FCC Part 15 Subpart J Class B, IC Class/classe B
Interface — Wide (16-bit) Ultra2 SCSI (“Fast 40”), multimode (can
be either LVD or single-ended, autosensing)
Protocol — Transparent to synchronous or asynchronous
communication
Data Rate — Up to 80 Megabytes per second
Maximum
Distance — Extends LVD SCSI bus as far as 25 m (82 ft.) with a single
unit, farther with daisychained units
User Controls — (4) Internal jumpers for termination; additional internal
jumpers are reserved
Indicators — LEDs:
(2) Front-mounted: Power and Busy;
(5) Internal: (4) Bus Type, (1) Busy;
An additional internal LED is reserved
Connectors — (2) Micro D68 female (see Appendix A for pinouts)
Power — 110 to 220 VAC, 50 to 60 Hz (autosensing)
Size — 2.9"H x 4.8"W x 7.8"D (7.4 x 12.2 x 19.8 cm)
Weight — 3.3 lb. (1.5 kg)

6
ULTRA2 SCSI LVD EXPANDER
2. Introduction
2.1 Overview
The Ultra2 SCSI LVD Expander is a Low Voltage Differential (LVD) 16-bit Wide
SCSI-bus extender. The Expander effectively divides the SCSI bus into two LVD or
SE (single-ended) segments—one segment connected to each of its two ports. The
Expander translates signals, and facilitates communication, between the segments.
When used in conjunction with an Ultra2 SCSI host adapter, the Expander
maintains backward compatibility with previous generations of devices on single-
ended segments, while retaining optimal performance and maximum cable length
of LVD. The Expander can also be used with an Ultra SCSI (“SCSI-3,” 40-MB-per-
second) host adapter to add Ultra2 devices to its bus and increase cable lengths.
Because it performs only signal-level translation, the Expander operates
transparently; users will hardly know it’s there. It places no limits on the quantity or
location of SCSI devices beyond the normal limits of the SCSI specification.
The Expander’s ports are “multimode,” meaning they can operate in single-
ended or LVD mode. (This selection is controlled automatically by a sensing signal
[DIFFSENSE] provided by the SCSI devices on the bus. As soon as you connect it
to the bus, the Expander will autoconfigure its ports as necessary.) Because of this,
you can use the Expander to effectively double the length of a single-ended SCSI
bus, or to access LVD peripherals farther away from your host adapter than the
normal maximum of 12 m (40 ft.). You can also connect two Expanders point-to-
point across as much as 24 m (80 ft.) of cable, as long as there aren’t any other
SCSI devices in-line between them.

7
CHAPTER 2: Introduction
The Expander supports all current SCSI operations and can handle data rates up
to 20, 40, or 80 megabytes per second, depending on the type of bus it’s
communicating with. Figure 2-1 shows a typical Expander application. If you’d like
to examine a block diagram of the Expander, refer to Appendix B.
Figure 2-1. One SCSI bus with two physical segments: Using an Expander to
access legacy single-ended devices with an LVD host adapter.
Single-Ended Segment
Single-Ended Devices LVD Devices Ultra2 SCSI LVD
Host Adapter
Ultra2 SCSI
LVD Expander
LVD Segment

8
ULTRA2 SCSI LVD EXPANDER
2.2 Features
• Supports legacy and Ultra2 SCSI devices on the same bus with LVD-to-LVD
extension or SE-to-LVD conversion:
– Fully backward-compatible with SCSI-1, SCSI-2 [Fast SCSI], and SCSI-3
[Ultra SCSI], and can be used with either Narrow or Wide buses.
– Has switchable internal termination.
• Transfers data at up to 80 Megabytes per second (on a 16-bit Wide bus) in
either direction.
• Supports as many as 16 SCSI devices.
• Does not require software or a SCSI ID.
• Can be used to extend your LVD bus as far as 25 m (82 ft.), or to create an
LVD link that extends your single-ended bus.
• Can be daisychained to achieve even higher distances.
• Transparent operation—requires no software and no SCSI ID.
• Supports arbitration, parity, disconnect/reconnect, and sync or async data
transfer.
• Can act as either a target or initiator on either connected SCSI-bus segment.
• LEDs show power status and bus activity at all times.
• Can optionally provide TERMPWR (terminator power) to either or both
attached bus segments, regardless of whether they’re LVD or SE. Handles
TERMPWR with a resetting circuit protector and backflow-preventing diodes.
2.3 The Complete Package
Besides the Ultra2 SCSI LVD Expander itself, you should have received its power
cord and this manual. If anything is missing or arrived damaged, call Black Box
right away.

9
CHAPTER 3: Configuration and Internal LEDs
3. Configuration and Internal LEDs
3.1 Opening the Expander
To configure the Ultra2 SCSI LVD Expander’s termination, or to get visual
confirmation of more information than the external LED can provide, you’ll need
to access the Expander’s internal jumpers and LEDs.
CAUTION!
To avoid receiving a potentially hazardous electric shock, make sure the
Expander is turned OFF and unplugged when you open it. You might
have to temporarily turn the unit ON after it has been opened in order to
observe its internal LEDs—be very careful if you do this!—but never
open the unit while the unit is ON.
Conversely, even while the Expander is OFF, you need to avoid
damaging its circuit board with static electricity. If possible, stand on an
anti-static mat when you open the Extender and wear anti-static gloves
or wrist straps. At the very least, ground yourself before you open the
Expander by touching something metal.
Take these steps to open the Expander:
1. Use a small Phillips-head screwdriver to unscrew the screws embedded in each
of the Expander’s four rubber feet. Remove the feet.
2. You’ll see the edges of the Expander‘s wraparound housing on the bottom of
the unit right next to the holes where the feet used to be. If necessary, gently
pry one of these edges slightly outward so that the housing doesn’t fit so
snugly.
3. Carefully slide the housing toward the back of the unit and remove it.

10
ULTRA2 SCSI LVD EXPANDER
Now you’re ready to set the jumpers. If you look at the open Expander from above,
with its front panel facing right and its rear panel facing left, the jumper posts and
internal LEDs will be arranged at the top and bottom edges of the circuit board,
something like this:
JP12 JP11 JP10 JP4 JP1
D7 D6
D4 D3 D2 D1
JP9 JP8 JP7 JP6 JP5 JP3 JP2
Jumpers will be on JP4 and JP9; a single wire going to the external LED will be
connected to the right-hand post on JP8; and the two wires going to the external
LED will be connected to JP7. All other jumper posts will be empty.
Jumper posts JP1, JP4, JP9, and JP12 control termination; their possible settings
are described in Section 3.1. Jumper posts JP7 and JP8 form the electrical
connection to the external Busy LED; don’t disturb this connection. The other
jumpers are reserved for factory testing and future use; don’t install anything on
them.
Board-mounted LEDs D1, D2, D4, D7, and D8 light in response to the
conditions described in Section 3.2. LED D3 is reserved for factory testing.

11
CHAPTER 3: Configuration and Internal LEDs
3.2 Configuring Termination
Both ends of any single-ended or LVD SCSI-bus segment attached to the Expander
need to be terminated in order to prevent electronic “echo” interference on the
bus that would degrade its performance. You can use the Expander’s internal
jumpers JP1, JP4, JP9, and JP12 to control this termination. JP1 and JP4 affect the
bus attached to Port B, while JP9 and JP12 affect the bus attached to Port A.
•Termination at the Expander (JP4 and JP9): How you should set jumpers JP4
and JP9, which control local termination at the Expander’s ports, depends on
how your cables will be attached to the Expander:
– For each port into which you will be directly plugging a single cable, so that
the SCSI-bus segment will start or end at that port, keep the jumper installed,
just as it comes from the factory. If a segment will start or end at Port A,
leave the jumper on JP9. If a segment will start or end at Port B, leave the
jumper on JP4.
Example: For simple conversion applications in which an LVD bus ends at
the Expander and a single-ended bus starts, or vice versa, leave both of these
jumpers installed.
– For each port into which you will be plugging two cables through a three-
connector adapter (not a stub cable!), so that the SCSI-bus segment will pass
through that port, remove the jumper. If a segment will pass through Port A,
remove the jumper from JP9. If a segment will pass through Port B, remove
the jumper from JP4.
Example: For applications in which you are allowing a segment of SE
devices to tap into an LVD bus without forcing the LVD bus to operate at
the data rate of the SE segment, remove the termination jumper for the port
attached to the LVD bus. If the SE segment ends at the Expander, leave the
termination jumper for the port attached to the SE segment installed. But if
the SE segment also passes through the Expander, remove that jumper as
well.
Refer to Figures 3-1 through 3-3 on the next page. In an application such as
that shown in Figure 3-1, both JP4 and JP9 should remain installed. In an
application like that in Figure 3-2, with the Expander in the middle of one
segment and at the end of another, remove the jumper for the port that’s
attached to the middle of the segment. In a wide-open application like that in
Figure 3-3, in which the Expander is in the middle of both segments, remove
both jumpers.

12
ULTRA2 SCSI LVD EXPANDER
Figure 3-1. Both segments end, and are terminated, at the Expander.
Figure 3-2. One segment passes through the Expander, while the other ends
and is terminated.
Figure 3-3. Both segments pass unterminated through the Expander.
Ultra2 SCSI
LVD Expander
Ultra2
SCSI LVD
Expander
Ultra2
SCSI LVD
Expander
Bus B
JP9 ON
JP9
OFF
JP9 OFF
JP4 OFF
JP4 ON
JP4 ON
Bus A
Bus A
Bus B
Multiconnector
ribbon cable
Multiconnector
ribbon cables
Bus A Bus A
Tape drive
Disk drive
Disk drive
Host adapter
Host adapter
Host adapter
DVD-ROM drive
Disk drive
Host adapter
Termination enabled
Termination
enabled
Termination
Enabled
Termination
enabled
Termination
enabled
Disk drive

13
CHAPTER 3: Configuration and Internal LEDs
•Termination at the Other End(s) of the Segment (JP1 and JP12): The JP1 and
JP12 jumper posts control whether or not the Expander provides TERMPWR
output to support remote termination.
To explain: Most of the current generation of SCSI host adapters, disk
drives, and other devices have built-in internal terminators, like those in the
Expander, that can be used to terminate the SCSI bus if that device happens to
be the first or last device attached to the bus. The remote ends of the SCSI-bus
segments that you’ll be attaching to the Expander will probably be able to be
terminated this way.
But if, on a SCSI segment that will be attached to the Expander, the first or
last device (or both) don’t have an internal terminator, you will need to attach
an external terminator to that device instead. (I) That external terminator will
need to draw its power from a “terminator power” (TERMPWR) voltage that
must be present on the SCSI bus. Most SCSI devices can be set to provide
TERMPWR.
NOTE
It’s easy to make mistakes when installing external SCSI termination. If
you’ll need to do so, please call Black Box Technical Support to discuss
your application.
If the remote termination for the segments that will be attached to the
Expander can be handled with another device’s internal terminator, or with
an external terminator that gets its TERMPWR from some other device(s), you
can leave jumper posts JP1 and JP12 in their factory-default setting (no
jumpers installed). But if you’ll need to use an external terminator that gets its
TERMPWR from the Expander for remote termination on a segment attached to
either of the Expander‘s ports, install a jumper on the posts for that port.
Install a jumper on JP12 to have the Expander provide TERMPWR on Port A.
Install a jumper on JP1 to have the Expander provide TERMPWR on Port B.
Refer to Figure 3-1 on the previous page. In that illustration, the host adapter
and disk drive both have enabled internal terminators. But if the host adapter
didn’t have an internal terminator and couldn’t provide TERMPWR, you
would have to install a jumper on the Expander’s JP12 posts. If the same were
true of the disk drive, you would have to install a jumper on the Expander’s
JP1 posts.

14
ULTRA2 SCSI LVD EXPANDER
3.3 Observing the Internal LEDs
After the Expander is open, you can attach the SCSI buses and power cord to the
Expander as described in Chapter 4, then turn the unit ON and examine the LEDs
mounted on the Expander’s circuit board. Be very careful not to touch the inside
of the Expander while it’s open!
The internal LEDs are in the locations shown in the board layout on page 10.
They have these meanings:
•D1: When lit, Port B is operating in single-ended mode.
•D2: When lit, Port B is operating in LVD mode.
•(D3: Reserved for factory testing.)
•D4: When steadily dark, either the Expander is OFF or not receiving power or
there is continuous heavy traffic on the attached SCSI-bus segments. When
steadily lit, the Expander is ON but there is no activity on the SCSI bus. When
flickering, the Expander is ON and there is a normal amount of traffic on the
attached SCSI-bus segments.
(Note that the Expander’s external Busy LED will behave in the opposite way:
dark with no activity, flickering with normal activity, steadily lit with heavy
activity.)
•D6: When lit, Port A is operating in single-ended mode.
•D7: When lit, Port A is operating in LVD mode.

15
CHAPTER 4: Installation and Operation
4. Installation and Operation
4.1 Connecting SCSI-Bus Cables
To attach the Ultra2 SCSI LVD Expander to one end of a SCSI-bus segment, run
SCSI cable from the desired port on the Expander to another SCSI device.
CAUTION!
Do not connect older (non-Ultra2) differential SCSI devices—also known
as “high-voltage differential” or “HVD” devices—to the Expander. This
could damage or destroy the Expander.
To tap the Expander into the middle of a segment, first turn OFF the
Expander’s internal termination for the port where you will make this
connection—see Section 3.2. Then get a “T”-style SCSI cable or adapter with three
or more connectors and plug one of its central connectors into that port. Finally,
run regular SCSI cables from the end connectors of the “T” cable/adapter to the
previous device and next device in the segment.
CAUTION!
The T adapter or cable must be wired so that it does not contain a
“stub” (does not branch)—stubbing/branching will cause your SCSI bus
to fail. Instead, the cable or adapter should be constructed so that all of
the wires run from one connector to the next, to the next, and so on, in
sequence. For LVD “T” connections, we suggest our 7-connector LVD
ribbon cable (product code EVMSCC22). For single-ended “T”
connections, we suggest our 5-connector Ultra SCSI ribbon cable
(product code EVMSCC16).
Keep in mind that the maximum cable lengths allowed on any SCSI bus are fairly
strict, though they vary by the type of bus and by the cable size and insulation. Table 4-1
lists the maximum recommended cable lengths for each type of single-ended (SE)
and low-voltage differential (LVD) SCSI interface that the Expander supports.
Table 4-1. Maximum Cable Lengths
Interface Maximum Distance
SCSI-1 SE 6 m (20 ft.)
Fast/Wide (SCSI-2) SE 3 m (10 ft.)
Ultra Wide (SCSI-3) SE Fewer than 5 devices: 3 m (10 ft.);
5 or more devices: 1.5 m (5 ft.)
Ultra2 Wide LVD Multiple devices: 12 m (40 ft.);
Two devices point to point: 25 m (82 ft.)

16
ULTRA2 SCSI LVD EXPANDER
4.2 Connecting AC Power and Observing External LEDs
Run the included power cord from the IEC 320 male inlet on the rear of the
Expander to a working AC outlet. Once you’ve plugged in the unit, flip the rocker
switch on the rear of the unit to turn the Expander ON. The green external Power
LED on its front panel should light immediately. The Expander should now be
ready for continuous operation.
The Expander’s Power LED is easy to spot, even when it’s dark; there is a special
cutout for it in the lower right-hand corner of the front panel. The amber Busy
LED isn’t so easy to see when it’s not lit; it’s embedded in the venting in the front
panel’s upper right-hand corner. However, the Busy LED will begin flashing as
soon as data begins flowing on either attached SCSI-bus segment. During
exceptionally heavy traffic conditions, the flashing might become so persistent that
the LED briefly appears to be steadily lit. (The Expander’s internal Busy LED, D4,
behaves in the opposite way—see Section 3.3.)

17
CHAPTER 5: Applications
5. Applications
5.1 Applications That Will Work
Here are several ways in which Ultra2 SCSI LVD Expanders can be used in a SCSI-
bus system, helping LVD and single-ended SCSI-bus segments to work as one
logical SCSI bus. (As always, each bus segment must be terminated at both ends.)
Figure 5-1 shows how to use an Expander to extend an Ultra SCSI (SCSI-3) bus
beyond its normal distance limits to reach faraway LVD devices.
Figure 5-1. Extending an Ultra SCSI bus.
Ultra2 SCSI
LVD Expander
(JP4 ON,
JP9 OFF)
Multiconnector
ribbon cable Bus B
32-bit
PCI bus Bus A
SE
LVD
Ultra SCSI
host adapter
Termination enabled
Termination
enabled
LVD devices, max cable 12 m (40 ft.);
top data rate in this configuration 40 MB/sec
Ultra SCSI and legacy
single-ended devices,
max cable 1.5 m (5 ft.)

18
ULTRA2 SCSI LVD EXPANDER
Figure 5-2 shows how Ultra2 SCSI devices and legacy devices can be mixed with
no speed degradation for the Ultra2 devices.
Figure 5-2. Adding legacy devices to an Ultra2 SCSI bus.
Figure 5-3 shows how to use a pair of Expanders to insert maximum LVD point-
to-point cable length into a single-ended SCSI bus. (Normal configuration rules for
SE segments still apply to the segments at either end of this Extender-to-Extender
link.)
Figure 5-2. Adding maximum LVD point-to-point cabling.
Ultra2 SCSI
LVD Expander
(JP4 ON,
JP9 OFF)
Two Ultra2 SCSI LVD Expanders with all
ports terminated and an LVD SCSI cable
between them up to 25 m (82 ft.) long
Multiconnector
ribbon cable
Bus B
3 m (10 ft.) max 3 m (10 ft.) max
32-bit
PCI bus Bus A
LVD
SE
SE SE
LVD
Ultra2 SCSI
host adapter
Termination enabled
Termination enabled
Legacy SE devices
Legacy SE devices Legacy SE devices
Ultra2 SCSI
LVD devices
running at top
speed

19
CHAPTER 5: Applications
5.2 Applications That Won’t Work
Here are two ways that you must avoid trying to use the Ultra2 SCSI LVD
Expanders.
Applications like that shown in Figure 5-4 won’t work, because devices on the left
must send data through more than two Expanders to reach the devices on the
right. Two is the maximum number of Expanders through which SCSI data can
pass.
Figure 5-4. An application with too many Expanders.
Applications like that shown in Figure 5-5 won’t work either, because you can’t
have two LVD segments connected by a SE segment. The two LVD devices would
attempt to communicate at 40 MHz, a transfer rate not supported by the SE
segment, and the system would fail.
Figure 5-5. An application with an SE segment between two LVD segments.
Ultra2 SCSI LVD Expanders
Ultra2 SCSI LVD Expanders
LVD LVD
SE
Ultra2 SCSI
Host Adapter
SCSI devices SCSI devices
LVD device