B&B Electronics 3PXCC4A User Manual

This manual covers the following B&B Electronics’ model serial
cards:

Four Port, Any Address, Any IRQ

RS-232/422/485 Serial Card

CE

Model 3PXCC4A

Documentation Number 3PXCC4A3001

Each of these models is an RS -232 serial card and uses the same printed
circuit board. The "1" and "2" suffix designates the number of ports on the card. The
model number of the card i s printed on a sticker on the board.

This product designed and manufactured in Ottawa, Illinois USA

of domestic and imported parts by

International Headquarters

B&B Electronics Mfg. Co. Inc.

707 Dayton Road -- P.O. Box 1040 -- Ottawa, IL 61350 USA

Phone [phone] -- General Fax [phone]

Home Page: www.bb-elec.com

Sales e-mail: orders@ bb-el ec.com

Technical Support e-mail : [e-mail]

-- Fax [phone]

-- Fax [phone]

European Headquarters

B&B Electronics Ltd.

Westlink Commercial P ark, Oranmore, Co. Galway, Ireland

Phone [phone] -- Fax [phone]

Home Page: www.bb-europe.com

Sales e-mail: orders@ bb-europe.com

Technical Support e-mail : [e-mail]

 B&B Electronics -- Revised August 2001

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Table of Contents

Chapter 1: Introduction and General Information ...........1

Features.................................................................................1

Specifications.........................................................................2

Chapter 2: Quick Installation Guide..................................3

Chapter 3: Windows Installation .......................................5

Checking Device Manager for Available Address/IRQ’s

(Windows 95/98)....................................................................5

Adding Serial Port(s) in Windows 95/98 8
Changing COM Port Resources in Windows 95/98 13

Checking Windows NT Diagnostics for Available

Address/IRQ’s (Windows NT 4.0)........................................16

Checking Windows 2000 for Available Address/IRQ’s ........19

Adding Serial Port(s) in Windows 2000 24

Chapter 4: Address and IRQ Setting...............................31

Address Switch Setup..........................................................31

Interrupt Jumper Setup ........................................................34

Shared IRQ Mode................................................................35

Chapter 5: Communication Jumper Settings.................36

RS-232 Mode.......................................................................36

RS-422 Mode.......................................................................36

RS-485 Mode.......................................................................37

RS-485 Operation..........................................................37

RS-422 and RS-485 Termination.........................................38

High Speed Mode ................................................................38

Chapter 6: Physical Hook-up and Troubleshooting......39

Pinouts.................................................................................39

RS-232 Pinouts..............................................................39

RS-422 Pinouts..............................................................40

RS-485 Pinouts..............................................................40

Communication Cable Data.................................................41

Troubleshooting ...................................................................42

Appendix A: Hardware I/O Map......................................A-1

Appendix B: Declaration of Conformity Statement.....B-1

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Chapter 1: Introduction and General Information

The B&B Electronics’ 3PXCC4A series serial interface cards are
designed for the IBM PC, XT, AT and compatibles. Ports are
configured as a standard DTE device, and connections are made on
RJ45 style connectors.

The 3PXCC4A cards offer exceptional setup flexibility. The
3PXCC4A series has the ability to use any I/O address and any
hardware interrupt. You can install as many serial ports as will
physically fit in a machine. To use one of the “non-standard”
addresses or interrupts, the serial software used must also offer that
flexibility. If you are writing your own application, be sure the
communications routines used support any address and IRQ. B&B
Electronics’ SimpCom Communications Drivers support these
features.

Features

Each port independently configurable for any hex address 0 to hex
3F8 including COM1 – COM4

Each port independently configurable for any interrupt: 2, 3, 4, 5, 6,
7, 10, 11, 12, 14, and 15

Shared IRQ capability with Interrpt Status Register
Each port independently configurable for RS-232/RS-422 or RS-485
Jumper selectable interrupts: 2, 3, 4, 5, 6, 7, 10, 11, 12, 14, and 15
Enhanced 16 bit Address Decoding
Baud rates up to 460.8K baud in RS-422/RS-485 Mode, 115.2K

baud in RS-232 Mode
16550A UARTs on all ports
RS-232 mode supports lines: TD, RD, RTS, CTS, DSR, DCD, and

DTR
RS-422/RS-485 mode supports lines: TD and RD
RTS control of RS-485 driver enable
Can be wired for half or full duplex RS-485 communications

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Specifications

Bus: IBM PC ISA Bus
Slot: Requires 1 full length slot for complete IRQ selectability. When

installed in a short slot, IRQ’s 10-15 will not be available.
Dimensions: 7.1 x 4.3 in (18 x 10.9cm)
I/O connection: RJ45 (8 conductor) connectors for all four ports
Character length: 5, 6, 7, or 8 bits
Parity: Even, odd or none
Stop bits: 1, 1.5, or 2
RS-232 Drivers:

Device: 75185 Transceiver
High level output voltage: 6.0 V minimum
Low level output voltage: -6.0 V minimum

Output current limited to

±10 mA

RS-232 Receivers:
Device: 75185 Transceiver
Input high threshold voltage: 1.5V
Input low threshold voltage: 0.75V
Device will withstand

±30V

RS-422/485 Driver/Receiver:
Device: 75ALS180
Differential driver output voltage: 1.5 - 6 V
Differential input high-threshold voltage: 0.2 V
Differential input low-threshold voltage: -0.2 V

Power Consumption:
RS-422/485 Mode without termination on drivers

+5V, 175mA, 875mW
+12V, 60mA, 720mW

-12V, 60mA, 720mW

RS-232 Mode

+5V, 165mA, 825mW
+12V, 80mA, 960mW

-12V, 80mA, 960mW

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Chapter 2: Quick Installation Guide

The following steps will help you install the Model 3PXCC4A Serial
Card. Please follow (step-by-step) the following numbered
instructions and refer to any corresponding chapters for more
details.

Before removing the card from the anti-static protective packaging.

• Discharge any static electricity buildup on your body by touching

• Avoid touching the gold connectors or other parts on the card

• Remove AC power from the computer and unplug the power

• Retain the ESD bag for handling the card.

Save the packaging for storage or shipping.

CAUTION: Electrostatic Sensitive Device.
Use ESD precautions for safe handling.

a large grounded metal surface or the metal chassis on
equipment connected to earth ground by a 3-wire power cord.

except as necessary. After setting the jumper, ground yourself
to the computer chassis before and while inserting the card.

cord before inserting the card.

1. Make sure you have an available ISA slot for installing your B&B

Electronics Serial Card. You may have to remove the cover of
your PC.

2. Determine what addresses and IRQ’s are free to use on your

PC by checking your operating system for unused addresses
and IRQ’s. Each port uses eight I/O address spaces starting at
the base address that you select. Each port I/O address and
interrupt request (IRQ) must be set as well. See “Checking
Device Manager for Available Address/IRQ’s” in Chapter 3 for
your operating system. Refer to Chapter 4 (Table 3) for
frequently unused I/O addresses and IRQ’s. Write down the
address and IRQ you select to use. Do not physically install the
ISA card at this point.

3. Add New Hardware – This consists of adding a port or ports to

your operating system. See “Adding Serial Ports” in Chapter 3
for specific instructions for your operating system.

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4. Assign Address and IRQ – The address and IRQ are set in the

operating system that you are using. This is the final step of
adding new hardware. See Chapter 4 for more details.

5. Set up the address (with dipswitches) and IRQ (jumpers) on the

serial card to reflect unused addresses and IRQ’s that you want
to use. The address dipswitch setting consists of configuring
seven dipswitches that reflect a particular hex address. The IRQ
is set via a little black jumper. See Chapter 4 for an explanation
of address and IRQ settings as well as details on configuring the
card itself.

6. Set serial card hardware jumpers for the communication

parameters that you desire. See Chapter 5 for an explanation of
serial parameters and details on how to configure them.

7. Shut down the PC before installing the serial card.

8. Install ISA serial card into an available ISA slot in the PC.

9. Physical Hook-up and Troubleshooting – pinout, cable data, and

troubleshooting information. See Chapter 6 for more details.

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Chapter 3: Windows Installation
Checking Device Manager for Available

Address/IRQ’s (Windows 95/98)

Click on Start / Settings / Control Panel and double-click on System
Properties.

Left-click on Device Manager.

Double-click on Computer.

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Left-click on Interrupt Request.

Find a free IRQ in the displayed list. Any number that is seen on

the left hand side of this screen is an IRQ that is currently being
used. The object is to find a number of IRQ(s) that are not listed and
set your port(s) using those IRQ’s.

Left-click on Input/Output (I/O).

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Scroll through the list, check 03F8H, 02F8H, 03E8H, 02E8H. If

one of these is available, use it. If not, check alternates.

Find a free address in the list. Most desktop PC’s have a COM1
and possibly a COM2 already on their system which will be seen in
the list. You might have to start at COM3 or COM4 to begin
addressing the ISA card. If these addresses are used you may have
to resort to the Frequently Unused Port Addresses (found in Chapter
4, Table 3) of this manual. Write these open addresses and IRQ’s
down for later reference.

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Adding Serial Port(s) in Windows 95/98

Go to Start Menu / Settings / Control Panel.
Run the Windows Add New Hardware utility found in the control

panel. Click Next.

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Click Next.

Select Yes/No for the device in the list. Click Next.

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Select No (you do not want Windows to search for your new
hardware). Click Next.

Select Ports (COM & LPT). Click Next.

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Select (Standard port types) and Communication Port. Click Next.

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The next screen will show the address and interrupt request of
the port. These may not match your configuration. For now, simply
click Next. Windows may ask for the Windows 95/98 disk/CD to be
inserted.

Finally, click Finish.

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Changing COM Port Resources in Windows 95/98

Click Start / Settings / Control Panel and double-click on System
Properties.

Click on Device Manager (make sure “View devices by type” is
enabled.

Double-click on Ports (COM & LPT).
Double-click on the new port that has been added.

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Click Resources.
Click off (check mark out of box) Use Automatic Settings.

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Click off (check mark out of box) Use Automatic Settings.

Select Basic Configuration 0007 (or last one).
Select Input / Output Range.
Click Change Setting.
Change Address to match the free address settings you found

earlier.
Click OK.
Select Interrupt Request.
Click Change Settings.
Change IRQ to match the free IRQ settings you found earlier.
At this point you can shut down the system and physically install

your B&B Electronics Serial Card into an available ISA slot. Double
check to make sure the addresses and IRQ’s on the Serial Card are
set to the correct settings.

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Checking Windows NT Diagnostics for Available
Address/IRQ’s (Windows NT 4.0)

Click on Start / Programs / Administrative Tools / Windows NT
Diagnostics.

Left-click on Resources.

Find a free IRQ in the following list. Any number that is seen on
the left hand side of this screen is an IRQ that is currently being
used. The object is to find a number of IRQ(s) not listed and set
your port(s) using those IRQ’s.

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Left-click on I/O Port in Resources. Tab to view currently used
addresses.

Scroll through the list, check 03F8H, 02F8H, 03E8H, 02E8H. If

one of these is available, use it. If not, check alternates.
Find a free address in the list. Most desktop PC’s have a COM1

and possibly a COM2 already on their system, which will be seen in
the list. You may have to start at COM3 or COM4 to start your
addressing of the ISA card you have. If these addresses are used
you may have to resort to the Frequently Unused Port Addresses
(found in Chapter 4, Table 3) of this manual. Write these open
addresses and IRQ’s down for later reference.

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Adding Serial Port(s) in Windows NT 4.0

Go to Start Menu / Settings / Control Panel.
Double-click on Ports.

Click Add.

Choose COM Port Number, Base I/O Address, and IRQ that you
want to use for the new Serial Port(s) being added.

After clicking OK, you will see a screen – System Setting
Change. Click the button Restart Now to restart Windows NT 4.0.

At this point you can shut down the system and physically install
your B&B Electronics Serial Card into an available ISA slot. Double
check to make sure the addresses and IRQ’s on the Serial Card are
set to the correct settings.

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Checking Windows 2000 for Available Address/IRQ’s

Click on Start / Settings / Control Panel.

Double-click on System.

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Click on Hardware.

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Click on Device Manager.

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Click on View (top of screen).
Click on Resources by type.
Double-click on Input/Output. Find an unused address to set your

B&B Electronics serial card to.

Scroll through the list, check 03F8H, 02F8H, 03E8H, 02E8H. If

one of these is available, use it. If not, check alternates.
Find a free address in the list. Most desktop PC’s have a COM1

and possibly a COM2 already on their system, which will be seen in
the list. You may have to start at COM3 or COM4 to start your
addressing of the ISA card you have. If these addresses are used
you may have to resort to the Frequently Unused Port Addresses
(found in Chapter 4, Table 3) of this manual. Write these open
addresses and IRQ’s down for later reference.

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Double-click on Interrupt Request (IRQ). Here you will need to find
an unused IRQ to set your B&B Electronics serial card to.

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Adding Serial Port(s) in Windows 2000

Go to Start Menu / Settings / Control Panel.

Double-click on Add/Remove Hardware.

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Click Next.
Click on Add/Troubleshoot a device.

Click Next.

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The following screen will appear after a few seconds.

Click Add a new device.
Click Next

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Click No, I want to select the hardware from a list.

Click Ports (COM & LPT).
Click Next.

Select Standard port types and Communication Ports and Click
Next. You will see the following screen, go ahead and Click OK.

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The Resources area will allow you to set the IRQ and address of
your new ports.

Click on the down arrow to the middle right of the screen after
“Setting based on”:

Click on the highest Basic configuration number in the list on the
“Setting based on” category.

Double-click on the Input/Output Range to set the Address.

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Double-click on the Interrupt Request to set the IRQ.

Select IRQ and Address that you want your port(s) configured at.

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At this point you can shut down the system and physically install
your B&B Electronics Serial Card into an available ISA slot. Double
check to make sure the addresses and IRQ’s on the Serial Card are
set to the correct settings.

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Chapter 4: Address and IRQ Setting
Address Switch Setup

A Windows PC has I/O port addresses and memory addresses.
Some devices use both types of addresses. I/O port addresses have
a 64K address space. Devices may decode all 16 address bits or
only some of the lower bits. Traditionally, serial cards have only
decoded 10 bits of the address bus. Recently this has begun to
cause address conflicts with full 16 bit decoded devices, most
notably between video cards and COM 4. B&B has solved these
conflicts by decoding all 16 bits of the ISA address bus. Address
settings in our ISA bus serial cards is set by DIP switches (selecting
bits 11-4) or jumpers.

CAUTION: Electrostatic Sensitive Device.
Use ESD precautions for safe handling.

B&B Electronics 3PXCC4A cards are factory configured for
COM1 (IRQ4), COM2 (IRQ3), COM3 (IRQ5), and COM4 (IRQ7). If
you plan on installing two of the four ports on the 3PXCC4A as
standard COM1 and COM2, you may leave the address and IRQ set
to the factory defaults for COM1 and COM2.

The 3PXCC4A cards use a 7-position DIP switch to program the
binary I/O address of each port on the card. Figure 1 is a drawing of
the printed circuit board that shows the locations of the setup
switches and jumpers on the 3PXCC4A cards.

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Figure 1. Silk Screen Plot of 3PXCC4A PCB

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When setting the address (via the dipswitch) use the silkscreen on
the printed circuit board. This silkscreen shows a “1” and a “0” to
refer to the “on and “off” states that each switch is set to. Switch S1
configures port one (labeled J1) and, on two port cards, switch S2
configures port two (labeled J2). Least significant bit (LSB) and most
significant bit (MSB) are labeled on the card. Table 1 shows the
numerical weight and electrical connection of each switch position.
Refer to Table 2 for COM port addresses. Table 3 shows frequently
unused port addresses for applications when COM port addresses
1-4 are already used.

Table 1. Address Switches

Switch Position 7 6 5 4 3 2 1
Bus Connection
Decimal Weight
Hex Weight

SA9 SA8 SA7 SA6 SA5 SA4 SA3
512 256 128 64 32 16 8
200 100 80 40 20 10 8

To install the 3PXCC4A card as COM1, 2, 3, or 4, follow the
switch settings shown in Table 2. To install at another address,
follow the switch settings shown in Table 3.

Table 2. Standard Port Addresses

Base Hex

Address

Binary

Equivalent

Switch Settings

MSB LSB

7654321

COM1
COM2
COM3
COM4

3F8 1111111000 1111111
2F8 1011111000 1011111
3E8 1111101000 1111101
2E8 1011101000 1011101

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Table 3. Frequently Unused Port Addresses

Base

Hex

Address

Binary

Equivalent

Switch

Settings

MSB LSB

I/O Space

Description

7654321
200
208
300
308
310
318
380
388
3A0
3A8

1000000000 1000000 game port
1000001000 1000001 game port
1100000000 1100000 prototype
1100001000 1100001 prototype
1100010000 1100010 prototype
1100011000 1100011 prototype
1110000000 1110000 SDLC
1110001000 1110001 SDLC
1110100000 1110100 bisync com
1110101000 1110101 bisync com

Interrupt Jumper Setup

The IRQ is a hardware Interrupt Request line in an ISA bus
expansion slot on a PC or AT compatible computer. The 8 bit PC
ISA slot has 8 interrupts, the 16 bit slot has another 7 since one of
the first 8 is used to link in the remaining 8. The IRQ is used by
devices to request immediate service by the main microprocessor.
When the IRQ line is set, the microprocessor stops whatever it’s
doing, saves status, checks which line was set, then jumps to code
to handle the interrupt. The processor then clears the interrupt and
returns to what it was doing before. IRQ lines are set by the internal
timer, keyboard, hard drive controller, PCI, USB controller, sound
card, serial ports, printer and more.

The 3PXCC4A cards allow the use of interrupts (IRQ) 2, 3, 4, 5,
6, 7, 10, 11, 12, 14, and 15. Table 4 shows the standard serial port
IRQ settings. Note: If two ports use the same IRQ setting, both ports
cannot use the serial port at once. Only one port at a time may
communicate.

Table 4. Standard IRQ Settings

COM1 IRQ4
COM2 IRQ3
COM3 IRQ4
COM4 IRQ3

34 Manual Document# 3PXCC4A3001

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Shared IRQ Mode

The 3PXCC4A card has the ability to share interrupts
among its ports. Shared IRQ mode should only be used if your
software supports this feature. If you are writing your own software,
B&B Electronics’ SimpCom V1.04 and later serial communications
library supports this feature.

When sharing ports, use JP5 to set each of the ports to be
used in shared mode to the SHARE position. JP6 must also be set
to the SHARE position. Each of the ports set to SHARE will use the
Port A IRQ. Therefore when sharing IRQs among two or more ports,
Port A must always be one of the shared ports.

Manual Document# 3PXCC4A3001 35

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Chapter 5: Communication Jumper Settings

This chapter will cover all of the jumper settings to set your B&B
Serial Card for the proper communications that you desire.

CAUTION: Electrostatic Sensitive Device.
Use ESD precautions for safe handling.

RS-232 Mode

To configure Port A for RS-232 mode, 5 jumpers must be
checked. The following settings will configure PORT A as RS-232.

1. The four jumpers of JP7 - must be set to the "232" (upper)
position.

2. The third jumper of JP8 must be set to the "232" (left) position.

The remaining jumpers of JP8 have no meaning in RS-232
mode and may be in either position.

RS-422 Mode

To configure Port A for RS-422 mode, 7 jumpers must be

checked. The following settings configure PORT A as RS-422.

1. The four jumpers of JP7 must be set to the "422" (lower)

position.

2. The top three jumpers of JP8 should be set to the 422 (right)

position. The bottom jumper of JP8 switches the 120

Ω

receiver termination resistor in or out. Typically this resistor
should not be used. In some cases using high baud rates and
very long cables, termination should be used.

Note that the EIA RS-422 Specification labels data lines with
an "A" and "B" designator. Some RS-422 equipment uses a "+" and
"-" designator. In almost all cases, the "A" line is the equivalent of
the "-" line and the "B" line is the equivalent of the "+" line. More
information on RS-422 communications can be found in B&B
Electronics’ free RS-422/RS-485 Application Note.

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RS-485 Mode

To configure Port A for RS-485 mode, 7 jumpers must be
checked. The following settings configure PORT 1 as RS-485.

1. The four jumpers of JP7 must be set to the "422" (lower)

position.

2. The top two jumpers of JP8 should be set to the 485 (left)

position. The third jumper of JP8 should be set to the 422/485
(right) position. The bottom jumper of JP8 switches the 120

Ω

receiver termination resistor in or out. Typically this resistor
should not be used. In some cases using high baud rates and
very long cables, termination should be used.

RS-485 Operation

RS-485 mode requires that the driver be enabled and
disabled as needed, allowing two or four-wire communications. To
set up the 3PXCC4A Serial Card up for two wire mode you can
simply jumper TD(A) to RD(A) (for your Data “-“) and TD(B) to
RD(B) (for your Data “+”). Use the Signal Ground for your return
path as the thrid wire in this configuration. For four wire mode you
simply use all four data lines and your signal ground for a return
path. The 3PXCC4A card uses the RTS control line to put the driver
in high-impedance or tri-state mode. With RTS control, software
must set the RTS bit to a logic 1 to enable the driver and logic 0 to
disable the driver.

The receiver can also be enabled and disabled, a useful
feature in two-wire communications to prevent the transmitted data
from "echoing back" on its own receiver. The RX 485 jumper for
each port determines the reciever mode. If the jumpers are placed in
the 485 position, the “echo” is turned off. This is achieved by
disabling the reciever when the driver is enabled. Placing these
jumpers in the 422 position will hold the reciever enabled at all
times. More information on RS-485 communications can be found in
B&B Electronics’ free RS-422/RS-485 Application Note.

Manual Document# 3PXCC4A3001 37

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RS-422 and RS-485 Termination

A 120Ω termination resistor has been provided for the RS­422/485 receivers. To enable the termination provided, the
termination jumper should be placed in the Rt IN position (left). If
you do not need to use termination, place the jumper in the Rt OUT
position (right). Termination should only be used when very long
cable runs are used with high baud rates. For example, with most
cables which are 4000 feet or shorter and have baud rates at 19.2K
baud or lower, termination is not required. Note that if the
termination is enabled (IN), the biasing of the RS-485 network is
altered and the value of the bias resistors will likely need to be
changed somewhere on the network. More information on
termination and biasing can be found in B&B Electronics’ free RS­422/RS-485 Application Note.

High Speed Mode

High data rates can be obtained with the 3PXCC4A cards by
adjusting JP16B and JP17B. This multiplies the clock speed
supplied to the UARTs by 4 times to 7.328MHz for all ports, allowing
data rates up to 460.8K baud in RS-422 and RS-485 modes. Note
that RS-232 does not support these extended baud rates.

To enable the X4 clock, simply move the shorting jumper
from JP16B (*1) to JP17B (*4). This jumper is shipped from the
factory in the standard clock (*1) position.

Note that serial software is not aware of the change in
oscillator frequency. For example, in the
baud rate to 57.6K baud in software will result in a actual baud rate
of 230.4K baud. It is important to note that increasing the baud rate
may not increase actual throughput. In heavy multitasking cases or
with a slow computer, the computer’s inability to respond to
interrupts quickly enough will cause large idle spaces between
characters. Increasing the baud rate to this point will not increase
actual throughput.

38 Manual Document# 3PXCC4A3001

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×4 position, setting the

Chapter 6: Physical Hook-up and Troubleshooting

This chapter will cover 3PXCC4A pinout, communication cable
data, and troubleshooting information.

Pinouts

RS-232 Pinouts

The 3PXCC4A Serial Cards are wired using RJ45 type
connectors for each port. The following table shows the pinout for
the RS-232 connections.

RJ45 Pin RS-232

Signal
1
2
3
4
5
6
7
8

RTS output 7 4

TD output 3 2

CTS input 8 5

RD input 2 3
DTR output 4 20
DSR input 6 6

DCD input 1 8

GND ---- 5 7

Direction Std. DB9

Pinout

Std. DB25

Pinout

Table 5. RS-232 Pinout Description

NOTE: RJ45 pin numbers are referenced from left to right when

looking into the connector receptacle with the component side of the
card facing upwards.

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RS-422 Pinouts

RS-422 mode supports transmit and receive data signals.
The pinouts of the RJ45 connector are given in Table 6. Figure 5
shows how to connect a typical RS-422/RS-485 full duplex
communication link.

RJ45 Pin RS-422

signal
1
2
3
4
5
6
7
8

TD(B) output 7 4

TD(A) output 3 2

RD(B) input 8 5

RD(A) input 2 3

NA NA 4 20
NA NA 6 6
NA NA 1 8

GND ---- 5 7

Direction MDB9

Pinout

MDB25

Pinout

Table 6. RS-422/RS-485 Pinout Description

RS-485 Pinouts

RS-485 mode supports both full and half duplex
communications (transmit and receive data signals). The pinouts of
the DB-9 connector are given in Table 6 (if full duplex
communication is used). Figure 5 shows how to connect a typical
RS-422/RS-485 full duplex communication link. Figure 6 shows how
to connect a typical RS-485 half duplex communication link.

40 Manual Document# 3PXCC4A3001

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3PXCC4A Serial Card

TD(B+) Pin 1

TD(A-) Pin 2
RD(B+) Pin 3

RD(A-) Pin 4

GND Pin 8

Figure 5. RS-422/RS-485 (Four Wire) Pinout Description

3PXCC4A Serial Card

TD(A-) Pin 2
TD(B+) Pin 1

RD(A-) Pin 4
RD(B+) Pin 3

GND Pin 8

Figure 6. RS-485 (Two Wire) Pinout Description

RS-422 Four Wire Device

RD(+)

RD(-)

TD(+)

TD(-)

GND

RS-485 Two Wire Device

DATA (-)

DATA (+)

GND

Communication Cable Data

The 3PXCC4A Serial Card communicates using RS-232,
RS-422, and RS-485 communications. The communication cable
specifications are 24AWG (wire gauge) and 30pF/ft. (capacitance
rating). Twisted pairs are ideal for the RS-422/RS-485 Cable in order
to suppress noise on the data line. B&B Electronics can provide this
communication cable for RS-232 or RS-422/RS-485 Applications.
The Model ETC8195 is a cable style that can be used for RS-232
Applications, and Model ETC8506 can be used for RS-422/RS-485
Applications.

Manual Document# 3PXCC4A3001 41

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Troubleshooting

If you are unable to communicate with the card from your software:

1. Consult your software manual to make sure it supports the
address and interrupt that you have configured.

2. Double check that the address and interrupt are properly set.

3. Try another software package for troubleshooting. Download
SimpTerm (DOS Terminal Emulator) or Comtest (Windows
Terminal Emulator) from B&B Electronics’ web site. SimpTerm
and Comtest are shareware Simple Terminal Emulators that can
be used to vary the setup of any serial card. Both can be
downloaded from the following site location.

http://www.bb-elec.com/support.asp

4. Troubleshooting with a Loopback Test

Load Simpterm or Comtest on the test PC. When loading
Simpterm you must set up the port address and IRQ you have set
on the B&B Electronics serial card.

Jumper TD to RD on the DB9 male connector located on the
serial card. You may have to make a “loopback connector” in order
to do this. This is done by jumping pin 2 and pin 3 of a DB9 female
connector and plugging it into the DB9 male port on the serial card.

To test the RS-232 handshake lines you can also jumper RTS to
CTS and DTR to DSR. When you raise the RTS line you should see
CTS also go high. When you raise the DTR line you should see DSR
also go high.

Send data from the Serial Port (B&B Electronics serial card) and
see if the data is echoed back to the port. When a character is typed
on the keyboard you must see a duplicate character after the first
character to verify that the same character was received. Perform
this test on all ports of your serial card to verify the ports can (or
cannot) transmit and receive data.

5. Call B&B Electronics' Technical Support at the number/s shown

below:

International/USA Office:

[phone], 8a.m. - 5:00 p.m. weekdays (Central USA Time).

European Office:

[phone], 8a.m. – 4:30 p.m. weekdays (UK).

42 Manual Document# 3PXCC4A3001

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B&B Electronics Ltd – Westlink Comm. Pk – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]

Appendix A: Hardware I/O Map

I/O Map of XT Class Machines

Hex Address Address Function in XT Class Machines
000-00F
020-021
040-043
060-063
080-083
0A0-0AF
200-20F
210-217
2E8-2EF
2F8-2FF
300-31F
320-32F
378-37F
380-38F
3B0-3BF
3D0-3D7
3E8-3EF
3F0-3F7
3F8-3FF

DMA controller (8237A)
interrupt controller (8259A)
timer (8253)
PPI(8255A)
DMA page register (74LS612)
NMI - non maskable interrupt
game port joystick controller
expansion unit
COM4 serial port
COM2 serial port
prototype card
hard disk
parallel print
SDLC
MDA - monochrome adapter and printer
CGA - color graphics adapter
COM3 serial port
floppy diskette controller
COM1 serial port

Manual Document# 3PXCC4A3001 Appendix A: Hardware I/O A-1

B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax [phone]

B&B Electronics Ltd – Westlink Comm. Pk – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]

I/O Map of AT Class Machines

Hex Address Address Function in AT Class Machines
000-01F
020-03F
040-05F
060-06F
070-07F
080-09F
0A0-0BF
0C0-0DF
0F0-0FF
1F0-1F8
200-20F
258-25F
278-27F
2E8-2EF
2F8-2FF
300-31F
378-37F
380-38F
3A0-3AF
3B0-3BF
3BC-3BE
3C0-3CF
3D0-3D7
3E8-3EF
3F0-3F7
3F8-3FF

DMA controller #1 (8237A-5)
interrupt controller #1 (8259A)
timer (8254)
keyboard (8042)
NMI - non maskable interrupt & CMOS RAM
DMA page register (74LS612)
interrupt controller #2 (8259A)
DMA controller #2 (8237A)
80287 math coprocessor
hard disk
game port joystick controller
Intel Above Board
parallel printer port 2
COM4 serial port
COM2 serial port
prototype card
parallel printer 1
SDLC or bisync com 2
bisync com 1
MDA - monochrome adapter
parallel printer on monochrome adapter
EGA - reserved
CGA - color graphics adapter
COM 3 serial port
floppy diskette controller
COM1 serial port

Any eight-byte space not used by one of the devices listed in the
table and not used by any other equipment in your system may be
used for the serial port.

A-2 Appendix A: Hardware I/O Manual Document# 3PXCC4A3001

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Appendix B: Declaration of Conformity Statement

Manufacturer’s Name: B&B Electronics Manufacturing Company
Manufacturer’s Address: P.O. Box 1040

707 Dayton Road
Ottawa, IL 61350 USA

Model Numbers: 3PXCC4A1A, 3PXCC4A1B, 3PXCC4A2A,
3PXCC4A2B
Description: RS-232 Serial Card
Type: Light industrial ITE equipment
Application of Council Directive: 89/336/EEC
Standards: EN 50082-1:1992 IEC 801 (-2, -3, -4)
EN 61000 (-4-2, -4-3, -4-4, -4-6)
EN 50082-1:1998

DECLARATION OF CONFORMITY

Michael J. Fahrion, Director of Engineering

Manual Document# 3PXCC4A3001 Declaration of Conformity B-1

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