Black Box MX625A User manual

MARCH 1997
MX625A
2-Channel Async TDM
CUSTOMER SUPPORT INFORMATION
Order toll-free in the U.S.: Call 877-877-BBOX (outside U.S. call 724-746-5500)
FREE technical support 24 hours a day, 7 days a week: Call 724-746-5500 or fax [phone]
Mailing address: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]

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2-CHANNEL ASYNC TDM
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 B 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.

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2-CHANNEL ASYNC TDM
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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2-CHANNEL ASYNC TDM
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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2-CHANNEL ASYNC TDM
TRADEMARKS USED IN THIS MANUAL
Any trademarks mentioned in this manual are acknowledged
to be the property of the trademark owners.

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2-CHANNEL ASYNC TDM
Contents
Chapter Page
1. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.2 Typical Application . . . . . . . . . . . . . . . . . . . . .11
3. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

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2-CHANNEL ASYNC TDM
1. Specifications
Number of Subchannels—(2), both operating
at the same rate
Transmission Format—Asynchronous
Data Rate—Up to 19,200 bps for main channel;
up to 9600 bps for sub-channels, see Table 1-1
for data-rate selection
Number of Data Bits—5, 6, 7, or 8
Stop Bits—1 or 2
Parity—Even, odd, or no parity (2 stop bits are
required for no parity)
Interface—V.24/RS-232, three 25-pin, female
connectors attached to the unit
Temperature—32 to 122°F (0 to 50°C)
Humidity—Up to 90%, non-condensing

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2-CHANNEL ASYNC TDM
Power—No AC power required; uses ultra-low power
derived from the data and control signals
Size—1.2"H x 4.4"W x 7.3"D (3.2 x 11.4 x 18.9 cm)
Weight—10 oz. (285 g)

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2-CHANNEL ASYNC TDM
Table 1-1. Strap Selection.
Strap Function Possible Definitions Normal
Identity Positions Factory
Setting
Data Selects the data 1 9600 bps
Rate rate on the 2 4800 bps
sub-channels 3 2400 bps 2400 bps
(same for both) 4 1200 bps
5 600 bps
6 300 bps
150 bps
Parity Selects parity for SW1 (Ch 1)
SW1 each channel SW2 (Ch 2)
SW2
OFF ODD ODD
ON EVEN
Stop Bit Selects number SW3 (Ch 1)
SW3 of stop bits for SW4 (Ch 2)
SW4 each channel
OFF 1 stop bit 1 stop bit
ON 2 stop bits
with 6, 7, or
8 data bits
Parity Selects parity SW5 (Ch 1)
Enable enable or disable SW6 (Ch 2)
SW5 for each channel
SW6 OFF ENABLE ENABLE
ON* DISABLE
Number Selects number SW7 SW8
of Data of data bits
Bits (same for each ON OFF 6 bits 7 bits
SW7 channel) OFF ON 7 bits
SW8 ON ON 8 bits

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2-CHANNEL ASYNC TDM
NOTE
When using no parity, 2 stop bits are necessary.

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2-CHANNEL ASYNC TDM
2. Introduction
The 2-Channel Async TDM is a full-duplex,
character-interleaved time-division multiplexor,
enabling two asynchronous terminals to share one
asynchronous modem or a multiplexor port. Its two
async sub-channels operate at the same data rate,
selectable up to 9600 bps. The main channel
operates at twice that rate—up to 19200 bps.
The 2-Channel Async TDM is compatible with
async character formats using 5, 6, 7, or 8 data bits.
Both sub-channels must use the same number of
data bits and the same total number of bits. The
async character format should have 1 parity bit and 1
or 2 stop bits. If the parity bit is not generated by the
DTE, the characters must have 2 stop bits. Parity of
each sub-channel can be independently set to odd or
even.
2.1 Features
• Full-duplex TDM
• Selectable data rates from 150 bps to
9600 bps
• No AC power required

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2-CHANNEL ASYNC TDM
• Easy to install and configure
• Miniature and lightweight
2.2 Typical Application
Figure 2-1 shows a typical application of the
2-Channel Async TDM.
Figure 2-1. Typical Application.
Async Terminals
Async Modem Async Modem
Computer
MX625A MX625A

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2-CHANNEL ASYNC TDM
3. Installation
Installation of the 2-Channel Async TDM is simple
and straightforward.
Refer to Table 1-1 for the factory setting. If the
factory setting does not suit your requirements,
you can change it as follows:
Remove the cover by pressing the four markings
on the sides.
Strapping information for individual straps is
printed on the PCB of the TDM.
1. Determine the data rate, which should be the
same for both channels, and strap DATA RATE
to the speed appropriate for your equipment.
The setting represents the rate of the sub-
channel.
2. Select the parity, even or odd, for each
channel, by strapping PARITY SELECT
(SW1 and SW2) to the appropriate position.
If no parity, select either even or odd.
3. Select the number of stop bits for each
channel by strapping STOP BITS (SW3
and SW4) to the appropriate position.

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2-CHANNEL ASYNC TDM
NOTE
When using No Parity, 2 stop bits are required.
4. Select parity enable or disable for each
channel by strapping PARITY ENABLE to the
appropriate position (SW5 and SW6).
5. Determine the number of data bits to suit your
equipment and strap DATA BITS (SW7 and
SW8) to the appropriate position. Use one
selection for both channels.
6. Refasten the cover. Connect each sub-channel
to your units by using straight-through cables,
and connect the main channels to the modem
or multiplexor.
Figure 3-1. Strapping Diagram.
DIP
Switches
1 Parity Select (Ch1)
2 Parity Select (Ch2)
3 Stop Bits (Ch1)
4 Stop Bits (Ch2)
5 Parity Enable (Ch1)
6 Parity Enable (Ch2)
7 Data Bits (Ch1)
8 Data Bits (Ch2)
Data
Rate
9600
4800
2400
1200
600
300
150

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2-CHANNEL ASYNC TDM
Table 3-1. Sub-Channel Cable.
V.24/RS-232 Pin No. Pin No.
Signal TDM Terminal
PG 1 1 (Optional)
TD 2 2
RD 3 3
RTS 4 4
CTS 5 5 (Optional)
DSR 6 6 (Optional)
SG 7 7
DCD 8 8 (Optional)
DTR 20 20
NOTE
Wires marked as “Optional” may be omitted, unless
required by the equipment connected to the TDM.

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NOTES

1000 Park Drive • Lawrence, PA 15055-1018 • 724-746-5500 • Fax [phone]
© Copyright 1997. Black Box Corporation. All rights reserved.