Rockwell Automation Allen-Bradley Logix5000 Owner's manual

Programming Manual
Logix5000 Controllers ASCII Strings
CatalogNumbers 1756-L1,1756-L55,1756-L61,1756-L62,1756-L63,1769-L31,1769-L32C,1769-L32E,1769-L35CR,1769-L35E,
1789-L60, 1794-L34, PowerFlex 700S/SE

Important User Information
Solid-state equipment has operational characteristics differing from those of electromechanical equipment. Safety
Guidelines for the Application, Installation and Maintenance of Solid State Controls (publication SGI-1.1 available from
your local Rockwell Automation sales office or online at http://www.rockwellautomation.com/literature/) describes some
important differences between solid-state equipment and hard-wired electromechanical devices. Because of this difference,
and also because of the wide variety of uses for solid-state equipment, all persons responsible for applying this equipment
must satisfy themselves that each intended application of this equipment is acceptable.
In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from
the use or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and
requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or
liability for actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or
software described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell Automation,
Inc., is prohibited.
Throughout this manual, when necessary, we use notes to make you aware of safety considerations.
Allen-Bradley, Rockwell Software, Rockwell Automation, and TechConnect are trademarks of Rockwell Automation, Inc.
Trademarks not belonging to Rockwell Automation are property of their respective companies.
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. Attentions help you identify a hazard, avoid a hazard, and recognize the consequence
SHOCK HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that dangerous voltage may be
present.
BURN HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that surfaces may reach
dangerous temperatures.
IMPORTANT
Identifies information that is critical for successful application and understanding of the product.

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 3
Summary of Changes
This manual contains new and updated information.
The following controllers are no longer supported in the Logix Designer
application, version 21.
Changes throughout this revision are marked by change bars, as shown in the
margin of this page.
There are a number of minor changes throughout this publication that were
made to clarify existing information. The major changes are listed below.
IMPORTANT
RSLogix 5000 programming software is now known as Studio 5000™ Logix Designer application, a
component of Studio 5000 Engineering and Design Environment.
Catalog Number Description
1756-L61 ControlLogix 5561 Controller
1756-L61S ControlLogix 5561S Controller
1756-L62 ControlLogix 5562 Controller
1756-L62S ControlLogix 5562S Controller
1756-L63 ControlLogix 5563 Controller
1756-L63S ControlLogix 5563S Controller
1756-L64 ControlLogix 5564 Controller
1756-L65 ControlLogix 5565 Controller
1768-L43 CompactLogix 5343 Controller
1768-L43S CompactLogix 5343S Controller
1768-L45 CompactLogix 5345 Controller
1768-L45S CompactLogix 5345S Controller
1769-L23E-QBF1 CompactLogix 5323E-QB1 Controller
1769-L23E-QBFC1 CompactLogix 5323E-QBFC1 Controller
1769-L23-QBFC1 CompactLogix 5323-QBFC1 Controller
1769-L31 CompactLogix 5331 Controller
1769-L32C CompactLogix 5332C Controller
1769-L32E CompactLogix 5332E Controller
1769-L35CR CompactLogix 5335CR Controller
1769-L35E CompactLogix 5335E Controller
Change Page
Updated sample project folder location. page 22
Updated data type editor image. page 23

4Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Summary of Changes
Notes:

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 5
Table of Contents
Preface Studio 5000 Engineering and Design Environment and
Logix Designer Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
In This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 1
Communicating with an ASCII Device
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Connect the ASCII Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Configure the Serial Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Configure the User Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Create String Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Read Characters from the Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Send Characters to the Device. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Enter ASCII Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Chapter 2
Processing ASCII Characters
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Extract a Part of a Bar Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Look Up a Bar Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Create the PRODUCT_INFO Data Type . . . . . . . . . . . . . . . . . . . . . 23
Search for the Characters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Identify the Lane Number. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Reject Bad Characters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Enter the Product IDs and Lane Numbers . . . . . . . . . . . . . . . . . . . . . . 25
Check the Bar Code Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Convert a Value. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Decode an ASCII Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Build a String . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
ASCII Character Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Table of Contents

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 7
Preface
Studio 5000 Engineering and
Design Environment and
Logix Designer Application
The Studio 5000™ Engineering and Design Environment combines engineering
and design elements into a common environment. The first element in the
Studio 5000 environment is the Logix Designer application. The Logix Designer
application is the rebranding of RSLogix™ 5000 software and will continue to be
the product to program Logix5000™ controllers for discrete, process, batch,
motion, safety, and drive-based solutions.
The Studio 5000 environment is the foundation for the future of
Rockwell Automation® engineering design tools and capabilities. It is the one
place for design engineers to develop all the elements of their control system.
In This Manual This manual shows how to manipulate ASCII strings in Logix5000 controllers.
This manual is one of a set of related manuals that show common procedures for
programming and operating Logix5000 controllers. For a complete list of
common procedures manuals, see the Logix 5000 Controllers Common Procedures
Programming Manual, publication 1756-PM001.
The term Logix5000 controller refers to any controller that is based on the
Logix5000 operating system, such as:
·CompactLogix controllers
·ControlLogix controllers
·DriveLogix controllers
·FlexLogix controllers
·SoftLogix5800 controllers

8Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Preface
Notes:

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 9
Chapter 1
Communicating with an ASCII Device
Introduction
You can exchange ASCII data with a device through the serial port of the
controller. For example, you can use the serial port to:
·read ASCII characters from a weigh scale module or bar code reader.
·send and receive messages from an ASCII triggered device, such as a
MessageView terminal.
In addition to the controller serial port, firmware revision 3.1 and greater of the
1756-EWEB EtherNet/IP Web Server module supports a socket interface that
lets Logix5000 controllers exchange ASCII data using TCP or UDP socket
services. See the EtherNet/IP Web Server User Manual, publication ENET-
UM0527, revision C or later.
Connection from the serial port of the controller to the ASCII device
42237

10 Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Chapter 1 Communicating with an ASCII Device
Connect the ASCII Device
1. On the serial port of the ASCII device, determine which pins send signals
and which pins receive signals.
2. Connect sending pins to corresponding receiving pins and attach jumpers.
3. Attach the cable shield to both connectors.
4. Connect the cable to the controller and the ASCII device.
If the communications Then wire the connectors
Handshake
Do not handshake
2 RDX
3 TXD
4 DTR
COMMON
6 DSR
7 RTS
8 CTS
9
1 CD
2 RDX
3 TXD
4 DTR
COMMON
6 DSR
7 RTS
8 CTS
9
1 CD
ASCII Device Controller
42231
2 RDX
3 TXD
4 DTR
COMMON
6 DSR
7 RTS
8 CTS
9
1 CD
2 RDX
3 TXD
4 DTR
COMMON
6 DSR
7 RTS
8 CTS
9
1 CD
ASCII Device Controller
42232

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 11
Communicating with an ASCII Device Chapter 1
Configure the Serial Port
1. On the Online toolbar in the controller project, click the controller
button.
2. Select the Serial Port tab.
3. Select User mode and enter the configuration settings for the serial port.
•Select the baud rate, data bits, parity, and stop bits.
•Select the Control Line option:
•For RTS Send Delay, enter the delay (in 20 ms units) between the time
the RTS signal turns on (high) and the time that data is sent. For
example, a value of 4 produces an 80 ms delay.
•For RTS Off Delay, enter the delay (in 20 ms units) between the time
the last character is sent and the time that the RTS signal turns off
(low).
4. Click Apply.
If And And this is the Select Then
You are not using a modem No Handshaking
You are using a modem Both modems in a point-to-point
link are full-duplex Full Duplex
Master modem is full-duplex
while slave modem is half-duplex master controller. Full Duplex
slave controller Half Duplex Check the Continuous Carrier check box.
All modems in the system are
half-duplex Half Duplex Clear the Continuous Carrier check box (default).

12 Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Chapter 1 Communicating with an ASCII Device
Configure the User Protocol
1. Select the User Protocol tab.
•Enter a buffer size that is greater than or equal to the greatest number of
characters in a transmission. (Twice the number of characters is a good
guideline.)
•For ABL or ARL instructions, enter termination characters to mark the
end of the data. For ASCII codes, see the back cover of this manual.
•For AWA instruction, enter append characters. For ASCII codes, see
the inside back cover of this manual.
•If the ASCII device is configured for XON/XOFF flow control, select
the XON/XOFF check box.
•If the ASCII device is a CRT or is pre-configured for half duplex
transmission, select the Echo Mode check box.
If the device sends Then Notes
One termination character •In the Termination Character 1 text box, type
the hexadecimal ASCII code for the first
character.
•In the Termination Character 2 text box, type
$FF.
For printable characters,
such as 1 or A, type the
character.
Two termination
characters In the Termination Character 1 and 2 text boxes, type the hexadecimal ASCII code for each character.
To append Then Notes
One character •In the Append Character 1 text box, type the
hexadecimal ASCII code for the first character.
•In the Append Character 2 text box, type $FF.
For printable characters,
such as 1 or A, type the
character.
Two characters In the Append Character 1 and 2text boxes, type
the hexadecimal ASCII code for each character.
42252

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 13
Communicating with an ASCII Device Chapter 1
•Select the Delete Mode:
2. Click OK.
If the ASCII device is Select Notes
CRT CRT •TheDEL character ($7F) and the character that precedes the DEL character are not sent to
the destination.
•If echo mode is selected and an ASCII instruction reads the DEL character, the echo returns
three characters: BACKSPACE SPACE BACKSPACE ( $08 $20 $08).
Printer Printer •The DEL character ($7F) and the character that precedes the DEL character arenot sent to
the destination.
•If echo mode is selected and an ASCII instruction reads the DEL character, the echo returns
two characters: / ($2F) followed by the character that was deleted.
None of the above Ignore The DEL character ($7F) is treated as any other character.

14 Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Chapter 1 Communicating with an ASCII Device
Create String Data Types
Store ASCII characters in tags that use a string data type.
1. In the controller organizer, right-click Strings and choose New String
Type…
2. Type a name for the data type.
3. Type the maximum number characters that this string data type will store.
4. Click OK.
42811
42812
orYou can use the default STRING data type. It stores
up to 82 characters.
You can create a new string data type to store the number of
characters that you define.
IMPORTANT
Use caution when you create a new string data type. If you later decide to change the size of the
string data type, you may lose data in any tags that currently use that data type.
If you Then
Make a string data type smaller ·The data is truncated.
·The LEN is unchanged.
Make a string data type larger The data and LEN is reset to zero.
42233

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 15
Communicating with an ASCII Device Chapter 1
Read Characters from the Device
As a general rule, before you read the buffer, use an ACB or ABL instruction to
verify that the buffer contains the required characters.
·An ARD or ARL instruction continues to read the buffer until the
instruction reads the required characters.
·While an ARD or ARL instruction is reading the buffer, no other ASCII
Serial Port instructions, except the ACL, can execute.
·Verifying that the buffer contains the required characters prevents the
ARD or ARL from holding up the execution of other ASCII Serial Port
instructions while the input device sends its data.
For additional information on ASCII Serial Port instructions, see Logix5000
Controllers General Instruction Set Reference Manual, publication 1756-RM003.
For example, the device sends s fixed number of characters, such as a bar code
reader:
EXAMPLE
A bar code reader sends bar codes to the serial port (channel 0) of the controller. Each bar code
contains 24 characters. To determine when the controller receives a bar code, the ACB instruction
continuously counts the characters in the buffer.
When the buffer contains at least 24 characters, the controller has received a bar code. The ARD
instruction moves the bar code to the bag_bar_code tag.
/
bar_code_count.EN
EN
DN
ER
ASCII Chars in Buffer
Channel 0
SerialPort Controlbar_code_count
Character Count 0
ACB
Grtr Than or Eql (A>=B)
Source A bar_code_count.pos
0
Source B 24
GEQ
EN
DN
ER
ASCII Read
Channel 0
Destination bag_bar_code
''
SerialPort Controlbar_code_read
String Length 24
Characters Read 0
ARD
42227

16 Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Chapter 1 Communicating with an ASCII Device
For example, the device sends a variable number of characters, such as a message
or display terminal.
EXAMPLE
Continuously test the buffer for a message.
·Because each message ends in a carriage return ($0D), the carriage return is configured as the
termination character in the Controller Properties dialog box, User Protocol tab.
·When the ABL finds a carriage return, its sets the FD bit.
When the ABL instruction finds the carriage return (MV_line.FD is set), the controller removes the
characters from the buffer, up to and including the carriage return, and places them in the MV_msg
tag.
/
MV_line.EN EN
DN
ER
ASCII Test For Buffer Line
Channel 0
SerialPort Control MV_line
Character Count 0
ABL
MV_line.FD EN
DN
ER
ASCII Read Line
Channel 0
Destination MV_msg
''
SerialPort Control MV_read
String Length 12
Characters Read 0
ARL
42226

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 17
Communicating with an ASCII Device Chapter 1
Send Characters to the Device
When you send characters to the device, you need to determine whether you will
always send the same number of characters each time and whether you want to
append terminations characters to the data.
For example, you always send the same number of characters and want to
automatically append one or two characters to the end of the data.
And then to always send the same number of characters:
EXAMPLE
When the temperature exceeds the high limit (temp_high is on), the AWA instruction sends five
characters from the string[1] tag to a MessageView terminal.
·The $14 counts as one character. It is the hex code for the Ctrl-T character.
·The instruction also sends (appends) the characters defined in the user protocol. In this example,
the AWA instruction sends a carriage return ($0D), which marks the end of the message.
temp_high EN
DN
ER
ASCII Write Append
Channel 0
Source string[1]
'$1425\1'
SerialPort Control temp_high_write
String Length 5
Characters Sent 6
AWA
42229
EXAMPLE
When the temperature reaches the low limit (temp_low is on), the AWT instruction sends nine
characters from the string[2] tag to a MessageView terminal. (The $14 counts as one character. It is the
hex code for the Ctrl-T character.)
temp_low EN
DN
ER
ASCII Write
Channel 0
Source string[2]
'$142224\01$r'
SerialPort Control temp_low_write
String Length 9
Characters Sent 9
AWT
42229

18 Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Chapter 1 Communicating with an ASCII Device
For example, you send a different number of characters each time and want to
automatically append one or two characters to the end of the data:
And then to send a different number of characters each time:
EXAMPLE
When alarm is on, the AWA instruction sends the characters in alarm_msg and appends a termination
character.
·Because the number of characters in alarm_msg varies, the rung first moves the length of
alarm_msg (alarm_msg.LEN) to the length of the AWA instruction (alarm_write.LEN).
·In alarm_msg, the $14 counts as one character. It is the hex code for the Ctrl-T character.
alarm Move
Source alarm_msg.LEN
5
Dest alarm_write.LEN
5
MOV EN
DN
ER
ASCII Write Append
Channel 0
Source alarm_msg
'$1425\1'
SerialPort Control alarm_write
String Length 5
Characters Sent 6
AWA
42229
EXAMPLE
When MV_update is on, the AWT instruction sends the characters in MV_msg.
·Because the number of characters in MV_msg varies, the rung first moves the length of MV_msg
(MV_msg.LEN) to the length of the AWT instruction (MV_write.LEN).
·In MV_msg, the $16 counts as one character. It is the hex code for the Ctrl-V character.
MV_update Move
Source MV_msg.LEN
10
Dest MV_write.LEN
10
MOV EN
DN
ER
ASCII Write
Channel 0
Source MV_msg
'$161365\8\1$r'
SerialPort Control MV_write
String Length 10
Characters Sent 10
AWT
42229

Rockwell Automation Publication 1756-PM013C-EN-P - November 2012 19
Communicating with an ASCII Device Chapter 1
Enter ASCII Characters
1. Double-click the value area of the Source.
A text entry box appears:
2. Enter the characters for the string.
3. Click OK.
IMPORTANT
This String Browser window shows the characters up to the value of the LEN
member of the string tag. The string tag may contain additional data, which
the String Browser window does not show.
42616
42615
Line feed ($0A)
New line ($0D$0A)
Carriage return ($0D)
The number of characters that you see in the
window. This is the same as the LEN member of the
string tag.
The maximum number of characters that the string
tag can hold.
Dollar sign ($24)
Single quote ($27)
Form feed ($0C)
Tab ($09)

20 Rockwell Automation Publication 1756-PM013C-EN-P - November 2012
Chapter 1 Communicating with an ASCII Device
Notes: