Black Box IC920A User manual

SEPTEMBER 1999
IC920A
Micro Async to Sync Converter
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]
ASYNC.
SYNC.
Micro Async ↔Sync
Converter

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MICRO ASYNC TO SYNC CONVERTER
FEDERAL COMMUNICATIONS COMMISSION
AND
INDUSTRY CANADA
RADIO FREQUENCY INTERFERENCE STATEMENTS
This equipment generates, uses, and can radiate radio frequency energy
and if not installed and used properly, that is, in strict accordance with the
manufacturer’s instructions, may cause interference to radio communication.
It has been tested and found to comply with the limits for a Class A computing
device in accordance with the specifications in Subpart J of Part 15 of FCC rules,
which are designed to provide reasonable protection against such interference
when the equipment is operated in a commercial environment. Operation of
this equipment in a residential area is likely to cause interference, in which case
the user at his own expense will be required to take whatever measures may be
necessary to correct the interference.
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 A 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 classe A prescrites dans le Règlement sur le
brouillage radioélectrique publié par Industrie Canada.
This product is CE certified.

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MICRO ASYNC TO SYNC CONVERTER
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.

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MICRO ASYNC TO SYNC CONVERTER
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.
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.

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MICRO ASYNC TO SYNC CONVERTER
CONTENTS
1. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Description. . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.1 Setting Internal Switches. . . . . . . . . . . . . . . 8
3.2 Switch Settings . . . . . . . . . . . . . . . . . . . . . . . 10
4. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.1 Connecting the Asynchronous Port . . . . . . 12
4.2 Connecting the Synchronous Port. . . . . . . 13
Appendix A: Asynchronous Port Connections
(Configured as DCE). . . . . . . . . . . . . . . . . . . . . 14
Appendix B: Synchronous Port Connections
(Configured as DTE). . . . . . . . . . . . . . . . . . . . . 15
Appendix C: Block Diagram. . . . . . . . . . . . . . . . . 17
TRADEMARKS
The trademarks mentioned in this manual are the sole
property of their owners.

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MICRO ASYNC TO SYNC CONVERTER
1. Specifications
Data Rates—Up to 19.2 kbps
Clocking—Provided by modem or multiplexor
Buffer—4-bit RTS override feature empties buffers
before dropping RTS, so you can use the
Converter in a polling environment
Data Transmission—Full- or half-duplex
Connectors—Async: DB25 female; Sync: DB25 male
Operating Temperature—32 to 140°F (0 to 60°C)
Altitude—Up to 15,000 feet (4572 m)
Humidity—Up to 95% noncondensing
Power—No external power required; uses power
from data and control signals on async side only
Size—0.75"H x 2"W x 3.2"D (1.9 x 5.1 x 8.1 cm)
Weight—2 oz. (0.06 kg)

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MICRO ASYNC TO SYNC CONVERTER
2. Introduction
2.1 Description
The Micro Async to Sync Converter gives asynchronous
hardware access to synchronous modems or
multiplexors. The Converter plugs directly into the
asynchronous RS-232 DTE port and connects via
RS-232 cable to the synchronous DCE device.
Drawing power from the RS-232 interface, the
Converter needs no AC power or batteries to operate
and supports data rates to 19.2 kbps. Because the
Converter automatically adjusts the synchronous data
rate to match the asynchronous DTE’s output rate, no
data-rate strapping is necessary. The Converter derives
clocking externally from the clock of the synchronous
DCE, and imposes no limit on data-block size.
Characters may be up to 11 bits long.
Measuring only 0.75"H x 2"W x 3.2"D (1.9 x 5.1 x 8.1
cm), the Converter is housed in a sturdy ABS plastic
case. It comes equipped with a DB25 male connector
and a DB25 female connector.

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MICRO ASYNC TO SYNC CONVERTER
2.2 Features
• Conforms to CCITT V.14 and V.22 standards
• Adapts asynchronous terminals to synchronous
modems and multiplexors
• Allows character lengths from 8 to 11 bits
• Requires no AC power or batteries
• Data rates to 19.2 kbps
• Automatically adjusts synchronous data rates
• Miniature size
• Accepts external clocking
• Made in the USA

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MICRO ASYNC TO SYNC CONVERTER
3. Configuration
You can configure the Converter via four internal
switches. Figure 3-1 shows where the switches are
on the printed circuit board.
Figure 3-1. Switch locations on the PC board.
3.1 Setting Internal Switches
The four switches shown in Figure 3-2 allow selection
of character length and extended signaling rate. These
switches are located internally on the Converter’s PC
board. To access them, use a small flathead screwdriver
to pop open the Converter’s case as shown in Figure 3-2.
Configuration Switches
Sync Male Connector (DTE)
Async Female Connector (DCE)

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MICRO ASYNC TO SYNC CONVERTER
Figure 3-2. Closeup of the Converter’s configuration switches.
Figure 3-3. Opening the Converter’s case with a small screwdriver.
OFF OFF OFF OFF
ON ON ON ON

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MICRO ASYNC TO SYNC CONVERTER
3.2 Switch Settings
All possible settings for the Converter’s configuration
switches are presented in Table 3-1. If you have
additional questions about configuration, call Black Box
Technical Support at 724-746-5500.
Switches SW1-1 and SW1-2 are set in combination to
determine the character length for asynchronous data.
Table 3-1. Switch Summary Table.
Position Function Factory Default
Switch 1-1 Character Length Off
Switch 1-2 Character Length Off
Switch 1-3 Signalling Rate Off -2.5% to 1%
Switch 1-4 Not Used
S WITCHES SW1-1
AND SW1-2: C HARACTER L ENGTH
Switches SW1-1 and SW1-2 are set in combination to
determine the character length for asynchronous data.
SW1-1 SW1-2
Off On 8 bit
On On 9 bit
Off Off 10 bit
On Off 11 bit
}10 bit

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MICRO ASYNC TO SYNC CONVERTER
S WITCH SW1-3: E XTENDED S IGNALING R ATE (ESR)
The setting for switch 1-3 determines the range of
variability the Converter looks for in asynchronous data
rates (the actual variance from a given frequency level
the Converter will tolerate).
SW1-3
Off -2.5% to +1%
On -2.5% to +2.3%
S WITCH SW1-4: N
OT U SED

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MICRO ASYNC TO SYNC CONVERTER
4. Installation
The Converter is designed to be used in pairs, with one
unit installed between an asynchronous DTE and a
synchronous DCE on either end of a synchronous
communciation link. Figure 4-1 illustrates a typical
Converter installation.
Figure 4-1. Typical Converter application.
4.1 Connecting the Asynchronous Port
The asynchronous port of the Converter is a DB25
female and is configured as DCE. Therefore, it wants to
talk to a DTE device such as a terminal or PC. You can
either plug the Converter directly into the DB25 serial
port of a DTE or connect it via “straight-through” cable.
Async DTE Async DTE
IC920A
IC920A
Sync DCE Sync DCE

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MICRO ASYNC TO SYNC CONVERTER
4.2 Connecting the Synchronous Port
The synchronous port of the Converter is a DB25 male
and is configured as DTE. Therefore, it wants to talk to
a DCE device such as a modem or a multiplexor. You
can plug the Converter directly into the DB25 serial port
of a DCE or connect it via “straight-through” cable.

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MICRO ASYNC TO SYNC CONVERTER
Appendix A: Asynchronous Port
Connections (Configured as DCE)
Pin Name Description
1 FG Frame Ground; connected straight through to synchronous
port
2 TXD Transmit Data (to Converter); data input from asynchronous
port; input to the Converter’s power supply
3 RXD Receive Data (from Converter); data output to asynchronous
port
4 RTS Request to Send (to Converter); input to the Converter’s
power supply
5 CTS Clear to Send (from the Converter); connected straight
through to synchronous port
6 DSR Data Set Ready (from the Converter); connected straight
through to synchronous port
7 SG Signal Ground; connected straight through to synchronous
port
8 CD Carrier Detect (from Converter); connected straight through to
synchronous port
9 +DCV Connected straight through to synchronous port
10 -DCV Connected straight through to synchronous port
20 DTR Data Terminal Ready (to Converter); input to Converter
power supply
22 RI Ring Indicator (from Converter); connected straight through to
synchronous port

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MICRO ASYNC TO SYNC CONVERTER
Appendix B: Synchronous Port
Connections (Configured as DTE)
Pin Name Description
1 FG Frame Ground; connected straight through to asynchronous
port
2 TXD Transmit Data (from Converter); data output to synchronous
port
3 RXD Receive Data (to Converter); data input from the synchronous
port; input to Converter’s power supply
4 RTS Request to Send (from Converter); 4-bit delay from
asynchronous port (Converter waits 4 bits before dropping
RTS to the synchronous port; this facilitates use in a polling
environment)
5 CTS Clear to Send (from Converter); connected straight through to
asynchronous port
6 DSR Data Set Ready (to Converter); connected straight through to
asynchronous port
7 SG Signal Ground; connected straight through to asynchronous
port
8 CD Carrier Detect (to Converter); connected straight through to
asynchronous port
9 +DCV Connected straight through to asynchronous port
10 -DCV Connected straight through to asynchronous port
15 TXC Transmit clock (to Converter); used to synchronize data
conversion from Converter to synchronous port

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MICRO ASYNC TO SYNC CONVERTER
Pin Name Description
17 RXC Receive clock (to Converter); used to synchronize data
conversion from Converter to synchronous port
20 DTR Data Terminal Ready (from Converter)
22 RI Ring Indicator (to Converter); connected straight through to
asynchronous port

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MICRO ASYNC TO SYNC CONVERTER
Appendix C: Block Diagram
Figure C-1. Block Diagram.
Micro Async
to Sync
Converter
Asynchronous
Format
ESR
2 TD
3 RD
17 RC
15 TC
4 RTS
RTS 4 RTS Delay
Phase Locked
Loop
TD 2
RD 3
Synchronous
Pins 1, 5, 6, 7, 8, 9, 10, 20, and 22 are connected straight through

1000 Park Drive • Lawrence, PA 15055-1018 • 724-746-5500 • Fax [phone]
© Copyright 1999. Black Box Corporation. All rights reserved.