Black Box RS-422 User manual

MAY 2002
IC971C
RS-422/485/530
Single-Port PCI Card
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]

1
FCC AND IC RFI 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.

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RS-422/485/530 SINGLE-PORT PCI CARD
• 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.
To meet FCC requirements, shielded cables and power
cords are required to connect this device to a personal
computer or other Class B certified device.
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 classe B prescrites dans le Règlement sur le
brouillage radioélectrique publié par Industrie Canada.

3
EU DECLARATION OF CONFORMITY
EUROPEAN UNION DECLARATION OF CONFORMITY
This equipment complies with the requirements of the
European EMC Directive 89/336/EEC.

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RS-422/485/530 SINGLE-PORT PCI CARD
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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NOM STATEMENT
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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RS-422/485/530 SINGLE-PORT PCI CARD
TRADEMARKS USED IN THIS MANUAL
OS/2 and PS/2 are registered trademarks of
International Business Machines Corporation.
Windows and Windows NT are either registered
trademarks or trademarks of Microsoft Corporation in
the United States and/or other countries.
Any other trademarks mentioned in this manual are
acknowledged to be the property of the trademark owners.

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CONTENTS
Contents
Chapter Page
1. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2 What the Package Includes . . . . . . . . . . . . 11
2.3 Factory-Default Settings. . . . . . . . . . . . . . . 11
2.4 Technical Description . . . . . . . . . . . . . . . . 11
2.5 RS-422/485/530 DB25 Male DTE
Connector Pin Assignments. . . . . . . . . . 12
3. Card Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.1 RS-485 Enable Modes . . . . . . . . . . . . . . . . 13
3.2 Clock Modes. . . . . . . . . . . . . . . . . . . . . . . . 15
3.2.1 RS-485 Mode and Clock Mode
Examples (Switch SW2) . . . . . . . 16
3.2.2 Baud Rates and Divisors
for D1 Mode . . . . . . . . . . . . . . . . . 17
3.3 Address and IRQ Selection . . . . . . . . . . . . 18
3.4 Line Termination. . . . . . . . . . . . . . . . . . . . 18

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RS-422/485/530 SINGLE-PORT PCI CARD
Contents (continued)
Chapter Page
4. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.1 Operating System Installation. . . . . . . . . . 20
4.1.1 For Windows Users . . . . . . . . . . . . . 20
4.1.2 Other Operating Systems. . . . . . . . 20
4.2 System Installation . . . . . . . . . . . . . . . . . . . 20
Appendix A. Troubleshooting. . . . . . . . . . . . . . . . . 22
A.1 Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
A.2 Calling Black Box. . . . . . . . . . . . . . . . . . . . 23
A.3 Shipping and Packaging . . . . . . . . . . . . . . 24
Appendix B. Electrical Interfaces . . . . . . . . . . . . . . 25
B.1 RS-422 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
B.2 RS-485 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
B.3 RS-530 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Appendix C. Asynchronous Communication. . . . . 28
Appendix D. Board Layout . . . . . . . . . . . . . . . . . . . 31

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CHAPTER 1: Specifications
1. Specifications
UART: 16850
Connector: (1) DB25 male
Interface: RS-422/485/530
Temperature Tolerance: Operating: 32 to 122°F (0 to
50°C); Storage: -4 to +158°F (-20 to +70°C)
Relative Humidity: 10 to 90%, noncondensing
MTBF: Greater than 150,000 hours (calculated)
Power: +5 VDC, 480 mA
Size: 2.5"H x 4.9"W (6.3 x 12.5 cm), excluding
goldfingers; 2.8"H x 4.9"W (7.1 x 12.5 cm), including
goldfingers
Weight: 2.8 oz. (79.4 g)

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RS-422/485/530 SINGLE-PORT PCI CARD
2. Introduction
2.1 Overview
The RS-422/485/530 Single-Port PCI Card is a one-
channel PCI Bus serial I/O adapter. It provides one
field-selectable RS-422/485/530 serial port that supports
asynchronous data rates up to 460.8 kbps.
Choose the RS-422 mode for long-distance device
connections up to 4000 ft. (1219.2 m) where noise
immunity and high data integrity are essential. Select
RS-485 and capture data from multiple peripherals in a
RS-485 multi-drop network. Up to 31 RS-485 devices can
be connected to each port to automate your data
collection.
In RS-485 mode, our special auto-enable feature allows
the RS-485 ports to be viewed by the operating system as
a COM: port. This means that the standard COM: driver
can be used for RS-485 communications. Our on-board
hardware automatically handles the RS-485 driver
enable.

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CHAPTER 2: Introduction
2.2 What the Package Includes
The PCI Card is shipped with the following items.
• (1) RS-422/485/530 Single-Port PCI Card.
• (1) Serial Utilities Software CD-ROM disk
containing drivers for Windows®3.1x/95/98/2000
and Windows NT®, Advanced COM drivers,
utilities, INF files, help files, and this users’ manual
in PDF format.
If either item is missing or damaged, contact Black Box
at 724-746-5500.
2.3 Factory-Default Settings
When shipped from the factory, the PCI Card’s DB25
port is configured as RS-530.
2.4 Technical Description
The PCI Card provides an additional asynchronous
serial port, field-selectable as RS-422/485/530 for
industrial automation and control applications.

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RS-422/485/530 SINGLE-PORT PCI CARD
The Card uses a 16850 UART. This chip features
programmable baud rates, data format, interrupt
control, and an industry-leading 128-byte FIFOs.
2.5 RS-422/485/530 DB25 Male DTE Connector Pin
Assignments
Signal Name Pin # Mode
G ND Ground 7 —
RDB RX+ Receive Positive 16 Input
RDA RX- Receive Negative 3 Input
CTSB CTS+ Clear To Send Positive 13 Input
CTSA CTS- Clear To Send Negative 5 Input
TDB TX+ Transmit Positive 14 Output
TDA TX- Transmit Negative 2 Output
RTSB RTS+ Request To Send Positive 19 Output
RTSA RTS- Request To Send Negative 4 Output
NOTE
These pin assignments meet the EIA/TIA/ANSI-530 DTE
standard.

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CHAPTER 3: Card Setup
3. Card Setup
3.1 RS-485 Enable Modes
RS-485 is ideal for multi-drop or network environments.
RS-485 requires a tri-state driver that will allow the
electrical presence of the driver to be removed from the
line. The driver is in a tri-state or high impedance
condition when this occurs. Only one driver may be
active at a time and the other driver(s) must be tri-
stated. The output modem control signal Request To
Send (RTS) is typically used to control the state of the
driver. Some communication software packages refer to
RS-485 as RTS enable or RTS block mode transfer.
One of the unique features of the RS-422/485/530
Single-Port PCI Card is the ability to be RS-485
compatible without the need for special software or
drivers. This ability is especially useful in Windows and
OS/2®environments where the lower-level I/O control
is abstracted from the application program. This ability
means that you can effectively use the PCI Card in an
RS-485 application with existing (that is, standard
RS-232) software drivers.

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RS-422/485/530 SINGLE-PORT PCI CARD
Switch SW2 is used to control the RS-485 mode
functions for the driver circuit. The selections are:
• Auto Enable (silk-screen “AT”). The Auto Enable
feature automatically enables/disables the RS-485
interface via on-board circuitry.
• RTS Enable (silk-screen “RT”). The RTS mode
uses the RTS modem control signal to enable the
RS-485 interface and provides backward
compatibility with existing software products.
• No Echo (silk-screen “NE”) is used to control the
RS-485 enable/disable functions for the receiver
circuit and determine the state of the RS-422/485
driver. The RS-485 Echo is the result of
connecting the receiver inputs to the transmitter
outputs. Every time a character is transmitted, it is
also received. This can be beneficial if the software
can handle echoing (that is, using received
characters to throttle the transmitter) or it can
confuse the system if the software does not. To
select the No Echo mode, choose silk-screen
position NE.

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CHAPTER 3: Card Setup
3.2 Clock Modes
The RS-422/485/530 Single-Port PCI Card uses a
unique clocking option that allows the end user to select
from “divide by 4” and “divide by 1” clocking modes.
SW2 positions 1 and 2 select the divide by 1 (silk-screen
“D1”) and divide by 4 (silk-screen “D4”) modes. (See
Appendix D for SW2’s location.)
To select the baud rates commonly associated with
COM: ports (that is, 2400, 4800, 9600, 19.2, …
115.2 kbps), set switch SW2 in the divide by 4 mode
(silk-screen “D4”).
To select the maximum data rate up to 460.8 kbps, set
switch SW2 in the divide by 1 (silk-screen “D1”) position.
Please refer to Table 3-1 on page 17 for these additional
data rates.
CAUTION
Do not set both switches ON or invalid clocking will occur.

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RS-422/485/530 SINGLE-PORT PCI CARD
3.2.1 RS-485 M ODE AND C LOCK M ODE E XAMPLES
(S WITCH SW2)
Figure 3-1. Switch SW2, RS-422, Divide by 4.
Figure 3-2. Switch SW2, RS-485 Auto Enabled,
with No Echo Divide by 4.
Figure 3-3. Switch SW2, RS-485 Auto Enabled, with Echo Divide by 4.
D D A R N
1 4 T T E
D D A R N
1 4 T T E
D D A R N
1 4 T T E

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CHAPTER 3: Card Setup
3.2.2 B AUD R ATES AND D IVISORS FOR D1 M ODE
Table 3-1 shows some common data rates and the rates
you should choose to match them if using the PCI Card
in D1 mode.
Table 3-1. Baud rates for D1 mode.
For this Data Rate Choose this Data Rate
1200 bps 300 bps
2400 bps 600 bps
4800 bps 1200 bps
9600 bps 2400 bps
19.2 kbps 4800 bps
57.6 kbps 14.4 kbps
115.2 kbps 28.8 kbps
230.4 kbps 57.6 kbps
460.8 kbps 115.2 kbps
If your communications package allows the use of baud
rate divisors, choose the appropriate divisor from
Table 3-2 on the next page.

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RS-422/485/530 SINGLE-PORT PCI CARD
Table 3-2. Divisors for D1 mode.
For this Data Rate Choose this Divisor
1200 bps 384
2400 bps 192
4800 bps 96
9600 bps 48
19.2 kbps 24
38.4 kbps 12
57.6 kbps 8
115.2 kbps 4
230.4 kbps 2
460.8 kbps 1
3.3 Address and IRQ Selection
The PCI Card is automatically assigned resources by
your motherboard BIOS. Only the I/O address may be
modified by you.
Adding or removing other hardware may change the
assignment of I/O addresses and IRQs.
3.4 Line Termination
Typically, each end of the RS-485 bus must have line-
terminating resistors (RS-422 terminates at the receive
end only). A 120-ohm resistor is across each RS-422/485
input in addition to a 1K-ohm pull-up/pull-down
combination that biases the receiver inputs. Switch SW1

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CHAPTER 3: Card Setup
allows customization of this interface to specific
requirements. Each switch position corresponds to a
specific portion of the interface. If multiple PCI Cards
are configured in an RS-485 network, only the boards on
each end should have switches T, P, and P ON. Refer to
Table 3-3 for each position’s operation:
Table 3-3. Switch positions for line termination.
Name Function
T Adds or removes the 120 ohm termination.
P Adds or removes the 1K ohm pull-down resistor in the RS-
422/RS-485 receiver circuit (Receive data only).
P Adds or removes the 1K ohm pull-up resistor in the RS-
422/RS-485 receiver circuit (Receive data only).
L Connects the TX+ to RX+ for RS-485 two-wire operation.
L Connects the TX- to RX- for RS-485 two-wire operation.
Figure 3-4. Switch SW1, Line Termination.
P P T L L