Allen-Bradley POINT I/O 1734-232ASC User manual

POINT I/O RS-232
ASCII Module
1734-232ASC
User Manual
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Important User Information
Because of the variety of uses for the products described in this
publication, those responsible for the application and use of these
products must satisfy themselves that all necessary steps have been
taken to assure that each application and use meets all performance
and safety requirements, including any applicable laws, regulations,
codes and standards. In no event will Allen-Bradley be responsible or
liable for indirect or consequential damage resulting from the use or
application of these products.
Any illustrations, charts, sample programs, and layout examples
shown in this publication are intended solely for purposes of
example. Since there are many variables and requirements associated
with any particular installation, Allen-Bradley does not assume
responsibility or liability (to include intellectual property liability) for
actual use based upon the examples shown in this publication.
Allen-Bradley publication SGI-1.1, Safety Guidelines for the
Application, Installation and Maintenance of Solid-State Control
(available from your local Allen-Bradley office), describes some
important differences between solid-state equipment and
electromechanical devices that should be taken into consideration
when applying products such as those described in this publication.
Reproduction of the contents of this copyrighted publication, in whole
or part, without written permission of Rockwell Automation, is
prohibited.
Throughout this publication, notes may be used to make you aware of
safety considerations. The following annotations and their
accompanying statements help you to identify a potential hazard,
avoid a potential hazard, and recognize the consequences of a
potential hazard:
WARNING
!
Identifies information about practices or
circumstances that can cause an explosion in a
hazardous environment, which may lead to personal
injury or death, property damage, or economic loss.
ATTENTION
!
Identifies information about practices or
circumstances that can lead to personal injury or
death, property damage, or economic loss.
IMPORTANT Identifies information that is critical for successful
application and understanding of the product.

Rockwell Automation
Support
Before you contact Rockwell Automation for technical assistance, we
suggest you please review the troubleshooting information contained
in this publication first.
If the problem persists, call your local Rockwell Automation
representative or contact Rockwell Automation in one of the
following ways:
Your Questions or Comments on this Manual
If you find a problem with this manual, please notify us of it on the
enclosed How Are We Doing form.
Phone United
States/Canada
1.440.646.5800
Outside United
States/Canada
You can access the phone number for your
country via the Internet:
1. Go to http://www.ab.com
2. Click on Product Support
(http://support.rockwellautomation.com)
3. Under Support Centers, click on Contact
Information
Internet ⇒1. Go to http://www.ab.com
2. Click on Product Support
(http://support.rockwellautomation.com)
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1Publication 1734-UM009A-EN-P - June 2002
Preface
Purpose of This Manual
This manual describes how to install, configure, and troubleshoot
your POINT I/O RS-232 ASCII module.
Who Should Use
This Manual
You must be able to use RSNetWorx for DeviceNet software or similar
configuration software to set this module. You must have the
capability to download and use Electronic Data Sheet (EDS) files.
We assume you know how to do this in this manual. If you do not,
refer to your software user manuals or online help before attempting
to use this module.
For Information on See
Chapter/
Appendix
Installing the RS-232 ASCII Module 1
Configuring Your RS-232 ASCII Module 2
Diagnostics 3
Specifications A
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Publication 1734-UM009A-EN-P - June 2002
Preface 2
Related Products and
Documentation
The following table lists related POINT I/O products and
documentation.
Catalog Number Description Related Publications
Communication
Adapter
DeviceNet Adapter (Cat. No. 1734-ADN) Installation Instructions 1734-IN007
Communication
Interface
DeviceNet Interface (Cat. No. 1734-PDN) Installation Instructions 1734-IN057
1734D Series 1734D Series 24V dc 8 In/8 Out Combo Module (Cat. No. 1734D-IB8XOB8E,
-IB8XOB8ES)
Installation Instructions 1734-5.20
1734D Series 24V dc 8 In/8 N.O. Relay Combo Module (Cat. No.
1734D-IB8XOW8, -IB8XOW8S)
Installation Instructions 1734-5.21
1734D Series 120V ac 8 In/8 Out Combo Module (Cat. No. 1734D-IA8XOA8,
-IA8XOA8S)
Installation Instructions 1734-5.22
1734D Series 120V ac 8 In/8 N.O. Relay Combo Module (Cat. No.
1734D-IA8XOW8, -IA8XOW8S)
Installation Instructions 1734-5.23
Wiring Base
Assemblies
Wiring Base Assembly with 8 Screw-Clamp or Spring-Clamp Removable
Terminal Blocks (Cat Nos. 1734-TB, -TBS)
Installation Instructions 1734-IN511
Wiring Base Assembly with 12 Screw-Clamp or Spring-Clamp Removable
Terminal Blocks (Cat Nos. 1734-TB3, -TB3S)
Installation Instructions 1734-IN013
AC Modules 120V ac 2 Input Module (Cat. No. 1734-IA2) Installation Instructions 1734-IN010
120/220V ac 2 Output Module (Cat. No. 1734-OA2) Installation Instructions 1734-IN009
220V ac 2 Input Module (Cat. No. 1734-IM2) Installation Instructions 1734-IN008
DC Modules 24V dc 2 Input Sink Module (Cat. No. 1734-IB2) Installation Instructions 1734-IN051
24V dc 4 Input Sink Module (Cat. No. 1734-IB4) Installation Instructions 1734-IN051
24V dc 2 Input Source Module (Cat. No. 1734-IV2) Installation Instructions 1734-IN052
24V dc 4 Input Source Module (Cat. No. 1734-IV4) Installation Instructions 1734-IN052
24V dc Electronically Protected 2 Point Output Module (Cat. No.
1734-OB2E)
Installation Instructions 1734-IN056
24V dc Electronically Protected 4 Point Output Module (Cat. No. 1734-0B4E) Installation Instructions 1734-IN056
Analog Modules 24V dc Analog 2 Current Input Module (Cat. No. 1734-IE2C) Installation Instructions 1734-IN053
24Vdc Analog 2 Current Output Module (Cat. No. 1734-OE2C) Installation Instructions 1734-IN054
24V dc Analog 2 Voltage Input Module (Cat. No. 1734-IE2V) Installation Instructions 1734-IN001
24Vdc Analog 2 Voltage Output Module (Cat. No. 1734-OE2V) Installation Instructions 1734-IN002
RTD Module RTD Input Module (Cat. No. 1734-IR2) Installation Instructions 1734-IN012
Thermocouple
Module
Isolated Thermocouple Input Module (Cat. No. 1734-IT2I) Installation Instructions 1734-IN011

Publication 1734-UM009A-EN-P - June 2002
Preface 3
Counter Modules 24V Encoder/Counter Module (Cat. No. 1734-IK) Installation Instructions
User Manual
1734-IN006
1734-UM006
5V Encoder/Counter Module (Cat. No. 1734-IJ) Installation Instructions
User Manual
1734-IN005P
1734-UM006
24V dc Very High Speed Counter Module (Cat. No. 1734-VHSC24) Installation Instructions
User Manual
1734-IN003
1734-UM003
5V dc Very High Speed Counter Module (Cat. No. 1734-VHSC5) Installation Instructions
User Manual
1734-IN004
1734-UM003
Relay Module 24V dc, 120V ac, and 240V ac 2 Relay Sink/Source Output Module (Cat. No.
1734-OW2)
Installation Instructions 1734-IN055
Field Power
Distributor
Field Power Distributor (Cat. No. 1734-FPD) Installation Instructions 1734-IN059
Expansion Power
Supply
24V dc Expansion Power Supply (Cat. No. 1734-EP24DC) Installation Instructions 1734-IN058
Catalog Number Description Related Publications
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Publication 1734-UM009A-EN-P - June 2002
Preface 4
Notes:

iPublication 1734-UM009A-EN-P - June 2002
Table of Contents
Chapter 1
Installing the RS-232
ASCII Module
General Information on the 1734-232ASC Module. . . . . . . . 1-1
Installing the Mounting Base/ Wiring Base Assembly . . . . . 1-1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Installing an I/O Module . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Installing the Removable Terminal Block . . . . . . . . . . . . . . 1-4
Removing a Mounting Base . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Wiring the 1734-232ASC Module . . . . . . . . . . . . . . . . . . . . 1-6
Cable Pinouts for Standard DB Connectors. . . . . . . . . . . . . 1-7
How to Install a Serial Network . . . . . . . . . . . . . . . . . . . . . 1-7
How to Read Serial Device Input Data from
the 1734-232ASC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
How to Write Serial Output Data to the 1734-232ASC . . . . . 1-9
Setting Up DeviceNet Communications . . . . . . . . . . . . . . . 1-10
Polled I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
Cyclic and Change of State I/O. . . . . . . . . . . . . . . . . . . 1-11
Setting Up the DeviceNet I/O Connections . . . . . . . . . . 1-11
Setting Up the Connection Timer (EPR) . . . . . . . . . . . . 1-12
Operating Mode Selections . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Transmit Handshake vs. Transmit Immediate Option. . . 1-13
Produce Immediate vs. Master/Slave Handshake Option 1-14
Pad vs. No Pad Option. . . . . . . . . . . . . . . . . . . . . . . . . 1-14
Chapter 2
Configuring Your RS-232
ASCII Module
About Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Configuration Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Adding the RS-232 ASCII Module to Your Network . . . . 2-4
Adding I/O Modules to Your Network . . . . . . . . . . . . . 2-5
Setting the RS-232 ASCII Module’s Parameters . . . . . . . . . . 2-6
Checking I/O Status and Viewing the EDS File. . . . . . . . . . 2-8
Configuration Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
Parameter List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
POINT I/O Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
Receiving Serial Data from the ASCII Device . . . . . . . . . 2-15
Setting Up the Receive Character Buffer Length. . . . . . . 2-15
Setting Up and Using Pad Mode . . . . . . . . . . . . . . . . . . 2-16
Setting Up and Using the Swap Bytes Mode . . . . . . . . . 2-17
Setting Up and Using Delimiter Operation . . . . . . . . . . 2-18
Receive String Data Type . . . . . . . . . . . . . . . . . . . . . . . 2-18
Setting Up the Scanner I/O Receive Size . . . . . . . . . . . . 2-19
Explicit Messages to Receive the Serial Data String . . . . 2-20
Status Byte Description . . . . . . . . . . . . . . . . . . . . . . . . 2-20
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Publication 1734-UM009A-EN-P - June 2002
Table of Contents ii
Transmitting Serial Data to the ASCII Device . . . . . . . . . . . 2-21
Setting Up the Transmit Character Buffer Length . . . . . . 2-22
Setting Up and Using the Transmit Delimiter. . . . . . . . . 2-22
Transmit String Data Assemblies . . . . . . . . . . . . . . . . . . 2-23
Transmit Handshake vs. Transmit Immediate Mode . . . . 2-24
Transmitting Serial Data . . . . . . . . . . . . . . . . . . . . . . . . 2-26
Setting Up the Scanner I/O Transmit Size . . . . . . . . . . . 2-26
Produce Immediate vs. Master/Slave Handshake Mode . 2-27
Explicit Messages to Transmit Serial Data String . . . . . . 2-28
Chapter 3
Diagnostics
Using the Indicators for Troubleshooting . . . . . . . . . . . . . . 3-1
Appendix A
Specifications
Specifications for the 1734-232ASC Module . . . . . . . . . . . . A-1
Appendix B
Using the 1734-232ASC Module
with the ControlLogix System
Application Examples
About These Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
Serial Port Connector . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
EDS Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
DeviceNet Data Details . . . . . . . . . . . . . . . . . . . . . . . . B-3
Sending Data Through the 1734-232ASC Module. . . . . . B-3
Receiving Data From the 1734-232ASC Module . . . . . . . B-3
Reading Data from the 1734-232ASC Module into
ControlLogix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-4
Transmitting Data from ControlLogix Through the
1734-232ASC Module . . . . . . . . . . . . . . . . . . . . . . . . . . B-6

1Publication 1734-UM009A-EN-P - June 2002
Chapter 1
Installing the RS-232 ASCII Module
General Information on
the 1734-232ASC Module
The 1734-232ASC RS-232 ASCII module provides a flexible DeviceNet
interface to a wide variety of RS-232 ASCII devices. The 1734-232ASC
module provides the communication connections to the ASCII device.
Installing the Mounting
Base/ Wiring Base
Assembly
The wiring base assembly (1734-TB or -TBS) consists of a mounting
base (cat. no. 1734-MB) and a removable terminal block (cat. no.
1734-RTB or -RTBS). You can install the assembly, or just the
mounting base. To install the mounting base/wiring base assembly on
the DIN rail, proceed as follows.
ATTENTION
!
POINT I/O is grounded through the DIN rail to
chassis ground. Use zinc-plated, yellow-chromated
steel DIN rail to assure proper grounding. Using
other DIN rail materials (e.g. aluminum, plastic, etc.)
which can corrode, oxidize or are poor conductors,
can result in improper or intermittent platform
grounding.
WARNING
!
When you connect or disconnect the Removable
Terminal Block (RTB) with field side power applied,
an electrical arc can occur. This could cause an
explosion in hazardous location installations.
Be sure that power is removed or the area is
nonhazardous before proceeding.
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Publication 1734-UM009A-EN-P - June 2002
1-2 Installing the RS-232 ASCII Module
1. Position the mounting base/wiring base assembly vertically
above the installed units (adapter, power supply or existing
module).
2. Slide the mounting base down allowing the interlocking side
pieces to engage the adjacent module or adapter.
3. Press firmly to seat the mounting base on the DIN rail. The
mounting base will snap into place.
4. To remove the mounting base from the DIN rail, remove any
installed module (and any module immediately to the right), and
use a small bladed screwdriver to rotate the DIN rail locking
screw to a vertical position. This releases the locking
mechanism. Then lift straight up to remove the mounting base.
5. Repeat this procedure for the next mounting base assembly.
TX
RX
Module
Status
Network
Status
1734
232ASC
NODE:
Mounting Base
Mechanical Keying
(orange)
Module Wiring Diagram
Module Locking Mechanism
Insertable I/O Module
RTB Removing Handle
Removable Terminal Block (RTB)
DIN Rail Locking Screw
(orange)
Slide-in Writable Label
Interlocking Side Pieces

Publication 1734-UM009A-EN-P - June 2002
Installing the RS-232 ASCII Module 1-3
Installing an I/O Module
The module can be installed before, or after base installation. Make
sure that the mounting base is correctly keyed before installing the
module into the mounting base. In addition, make sure the mounting
base locking screw is positioned horizontal referenced to the base.
1. Using a bladed screwdriver, rotate the keyswitch on the
mounting base clockwise till the number required for the type of
module being installed aligns with the notch in the base.
1734-232ASC - Position 2
2. Make certain the DIN rail
locking screw is in the
horizontal position. (You
cannot insert the module if
the locking mechanism is
unlocked.)
3. Insert the module straight down into
the mounting base and press to
secure. The module will lock into
place.
WARNING
!
When you insert or remove the module while
backplane power is on, an electrical arc can occur.
This could cause an explosion in hazardous location
installations.
Be sure that power is removed or the area is
nonhazardous before proceeding.
Turn the keyswitch to align
the number with the notch.
Notch
(position 3 shown)
Make sure the DIN rail
locking screw is in the
horizontal position.
24VDC
Source
Output
Module
Status
Network
Status
1734
OB4E
NODE:
0
1
2
3
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Publication 1734-UM009A-EN-P - June 2002
1-4 Installing the RS-232 ASCII Module
Installing the Removable
Terminal Block
A removable terminal block is supplied with your mounting base
assembly. To remove, pull up on the RTB handle. This allows the base
to be removed and replaced as necessary without removing any of the
wiring. To reinsert the removable terminal block, proceed as follows.
1. Insert the RTB end opposite the handle into the base unit. This
end has a curved section that engages with the mounting base.
2. Rotate the terminal block into the mounting base until it locks
itself in place.
3. If an I/O module is installed, snap the RTB handle into place on
the module.
WARNING
!
When you connect or disconnect the Removable
Terminal Block (RTB) with field side power applied,
an electrical arc can occur. This could cause an
explosion in hazardous location installations.
Be sure that power is removed or the area is
nonhazardous before proceeding.
Hook the RTB end into
the mounting base end,
and rotate until it locks
into place.

Publication 1734-UM009A-EN-P - June 2002
Installing the RS-232 ASCII Module 1-5
Removing a Mounting Base
To remove a mounting base, you must remove any installed module,
and remove the removable terminal block (if wired).
1. Unlatch the RTB handle on the I/O module.
2. Pull on the RTB handle to remove the removable terminal block.
3. Press in on the module lock on the top of the module and pull
up on the I/O module to remove from the base.
4. Remove the module to the right of the base you are removing.
(The interlocking portion of the base sits under the adjacent
module.)
5. Use a small bladed screwdriver to rotate the orange DIN rail
locking screw on the mounting base to a vertical position. This
releases the locking mechanism.
6. Then lift the mounting base straight up to remove.
WARNING
!
When you connect or disconnect the Removable
Terminal Block (RTB) with field side power applied,
an electrical arc can occur. This could cause an
explosion in hazardous location installations.
Be sure that power is removed or the area is
nonhazardous before proceeding.
WARNING
!
When you insert or remove the module while
backplane power is on, an electrical arc can occur.
This could cause an explosion in hazardous location
installations.
Be sure that power is removed or the area is
nonhazardous before proceeding.
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Publication 1734-UM009A-EN-P - June 2002
1-6 Installing the RS-232 ASCII Module
Wiring the
1734-232ASC Module
Module Terminations
0Tx1
1Rx2
2NC
3NC
4NC
5NC
6NC
7SG
1 Tx is transmit from the 232ASC module.
2 Rx is receive into the 232ASC module.
Module
Status
Network
Status
1734
232ASC
1734
232ASC
NODE:
TxD
RxD
43123
Rx
NC
NC
SG
Tx
NC
NC
NC
Module Status
Network Status
Tx = Transmit Rx = Receive
NC = No Connection SG = Signal Ground
Shielded Cable: The 1734-232ASC module
requires shielded cable to help reduce the
effects of electrical noise coupling. Ground
each shield at one end only. A shield grounded
at both ends forms a ground loop, which can
cause module communications to fault. Never
connect a shield to the common side of a logic
circuit (this would introduce noise into the
logic circuit).
Connect the shield directly to a chassis ground.
This chassis ground connection is not available
on the 1734-232ASC RTB (Removable Terminal
Block). On a POINT I/O system, the chassis
ground connection can be made at the DIN
Rail, at the metal panel the DIN Rail is
mounted to, or at the user’s I/O device.
01
23
45
67
Tx
NC
NC
NC
Rx
NC
NC
SG
43124
Tx = Transmit Rx = Receive
NC = No Connection SG = Signal Ground

Publication 1734-UM009A-EN-P - June 2002
Installing the RS-232 ASCII Module 1-7
Cable Pinouts for
Standard DB Connectors
How to Install a Serial
Network
The communication between your serial device(s) and the
1734-232ASC is an RS-232 3-wire network.
1. Connect an appropriate cable to your device.
2. Connect the other end of the cable to the 1734-232ASC using the
three designated positions on the 1734-TB terminal block.
Notice the terminal markings on the 1734-232ASC case.
3. Turn on power to the serial device and the 1734-232ASC.
4. Set up the ASCII buffer sizes on the 1734-232ASC.
The defaults are 20 and 20. If more than 20 bytes are required
for the transmit or receive buffers, set the appropriate
parameters in your configuration file to the buffer size you need
for your ASCII data.
This will modify the I/O message size. You will need to
reconfigure the poll/COS/cyclic transmit and receive data sizes if
you modify the ASCII buffer size from the default value.
In many configuration tools, this will unmap the data in your
scanner’s scan list. They must be remapped in order to process
the data in your PLC or PC software. These values are displayed
in the Parameter Object, Class 15 (Fhex).
Table 1.1 RS-232 Functions
Pin Number
Function DB-25 DB-9
Transmit Data (TXD) 2 3
Receive Data (RXD) 3 2
Signal Ground (SG) 7 5
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Publication 1734-UM009A-EN-P - June 2002
1-8 Installing the RS-232 ASCII Module
5. The 1734-232ASC produces and consumes the number of ASCII
characters selected plus four.
These produce and consume sizes are presented for your
information in parameters 13 and 23, respectively.
How to Read Serial Device
Input Data from the
1734-232ASC
1. Connect to the 1734-232ASC from your configuration tool.
2. Connect the serial side of the 1734-232ASC to your computer’s
serial port or another serial device.
3. Go to the device configuration screen in the configuration tool.
4. Make sure that the 1734-232ASC is in the default factory
configuration.
5. Set the baud rate and framing format of the serial port to the
baud rate and framing format of the serial device that you are
using.
6. Put the configuration tool in monitor mode.
7. Direct the device that you are communicating with to send data.
For example, if you are connected to a computer terminal
program, type a message into the terminal. When you hit enter,
the module will update the data with the message that you
typed, and increment the transaction ID.
The default assembly of the poll response message is shown
below.
TIP Make sure that you set up your scanner to the
correct sizes using this data.
Table 1.2 Default Receive Data Assembly Format (Default Mode)
Byte 1 Byte 2 Byte 3 Byte 4 Byte 5-23 Byte 24
RX Transaction ID
Byte
Status Byte Reserved Length ASCII Data <CR>
(Terminator)

Publication 1734-UM009A-EN-P - June 2002
Installing the RS-232 ASCII Module 1-9
How to Write Serial Output
Data to the 1734-232ASC
1. Connect to the 1734-232ASC from your configuration tool.
2. Connect the serial side of the 1734-232ASC to your computer’s
serial port or another serial device.
3. Go to the device configuration screen in the configuration tool.
4. Make sure that the 1734-232ASC is in the default factory
configuration.
5. Set the baud rate and framing format of the serial port to the
baud rate and framing format of the serial device that you are
using.
6. Enter the serial data that you wish to send in the transmit data
parameter and choose apply.
7. Change the length of the data in the length byte to reflect the
length you wish to send and choose apply.
8. Change the transmit transaction ID and choose apply.
The 1734-232ASC will generate the characters you typed on the
computer screen.
Poll messages work in the same manner as the parameter object
interface.
Table 1.3 Default Transmit Data Assembly Format (Default Mode)
Byte 1 Byte 2 Byte 3 Byte 4 Byte 5-23 Byte 24
Reserved TX Transaction ID
Byte
Reserved Length ASCII Data <CR>
(Terminator)
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Publication 1734-UM009A-EN-P - June 2002
1-10 Installing the RS-232 ASCII Module
Setting Up DeviceNet
Communications
The 1734-232ASC module supports 4 modes of data transfer of the
serial buffer:
•Polled I/O
•Change of State I/O
•Cyclic I/O
•Explicit Message
Polled I/O
The 1734-232ASC module monitors the transaction ID for a change in
the transaction ID. If the transaction ID changes, then the
1734-232ASC module transmits the data buffer on its serial link. If the
transaction ID does not change, then the device does not transmit the
data buffer.
After the device has transmitted its data out to the serial link, the
1734-232ASC module then takes any information that is stored in its
current serial input buffer and sends this data to the DeviceNet master.
It sends all characters up to and including the received delimiter,
including pad characters if not deselected.
When the 1734-232ASC module receives a new message (either with a
delimiter or with an overflow condition without a delimiter) the
device then increments the receive record, updates the length byte,
and copies the new information from the last receive delimiter into
the buffer. If an overflow occurs, the 1734-232ASC module indicates
so in its receive status bit. The receive status byte also reflects parity
errors in the device.