Allen-Bradley Logix5000 Series User guide

CompactFlash File
System on
Logix5000
Controllers
1756-L61, 1756-L62, 1756-L63,
1756-L64, 1756-L60M03SE
Application Solution

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.ab.com/manuals/gi)
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.
CompactFlash, Logix5000, Allen-Bradley, Rockwell Automation, TechConnect, PowerFlex, CompactLogix, ControlLogix, and RSLogix 5000
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.
IMPORTANT Identifies information that is critical for successful application
and understanding of the product.
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
•recognize the consequence
SHOCK HAZARD
Labels may be on or inside the equipment (e.g., drive or motor) to
alert people that dangerous voltage may be present.
BURN HAZARD Labels may be on or inside the equipment (e.g., drive or motor) to
alert people that surfaces may reach dangerous temperatures.

3Publication LOGIX-AP007B-EN-P - January 2007
Table of Contents
Important User Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Preface Purpose of This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Who Should Use This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Additional Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Chapter 1
CompactFlash Card
Enhancements Overview
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
CompactFlash Card Enhancements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Sample File Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
CompactFlash File System Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Possible Applications of the CompactFlash File System . . . . . . . . . . . . 9
Chapter 2
CompactFlash File System
Restrictions
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Restrictions of the File System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Number of Open Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Maximum Data Per Message. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Removal and Insertion of CompactFlash Card . . . . . . . . . . . . . . . 11
Minimum File Size/Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Memory Resources and Performance. . . . . . . . . . . . . . . . . . . . . . . 12
Controllers Supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Limited Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Read or Write Portions of a File . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Number of Files that Can Be Created . . . . . . . . . . . . . . . . . . . . . . 12
Chapter 3
CompactFlash Commands Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
CF_Data_Working Tag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Create Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Set Up the Create Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Write Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Set Up the Write Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Read Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Set Up the Read Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Delete Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Set Up the Delete Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Determine the Number of Bytes to Read or Write . . . . . . . . . . . . . . . 19
Chapter 4
Example Application Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Configure Message Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Set the Controller Slot Number . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Create a File on the CompactFlash Card . . . . . . . . . . . . . . . . . . . . . . . 23

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4Table of Contents
Write Data to the CompactFlash Card . . . . . . . . . . . . . . . . . . . . . . . . . 26
Read Data from the CompactFlash Card . . . . . . . . . . . . . . . . . . . . . . . 28
Delete a File on the CompactFlash Card . . . . . . . . . . . . . . . . . . . . . . . 29
Build an Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Set Up Recipe Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Create the File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Write the Recipe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Read the Recipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Delete the Recipe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Appendix A
Format a CompactFlash Card Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Format with a Personal Computer and a CompactFlash Card Reader 35
Format RSLogix 5000 Software and a Logix5000 Controller with
CompactFlash Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Appendix B
Performance Data Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Performance Data Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Access 450 Bytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Access 4500 Bytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Access 4500 Bytes with an HMI Load . . . . . . . . . . . . . . . . . . . . . . 44
Access 4500 Bytes with 16 Message Instructions. . . . . . . . . . . . . . 44
Access 4500 Bytes and Periodic Tasks . . . . . . . . . . . . . . . . . . . . . . 44
Appendix C
Troubleshoot the CompactFlash
File System
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Status User-defined Data Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Tag Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Message Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Appendix D
Expand the Code to Support More
than 4500 Bytes of Data
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Modify the Application to Access More Data . . . . . . . . . . . . . . . . . . . 49
Access 10,000 Bytes Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Modify the Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Modify the Data Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Rockwell Automation Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Installation Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
New Product Satisfaction Return . . . . . . . . . . . . . . . . . . . . . . . . . . 57

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Preface
Purpose of This Manual
This manual describes how you can use the CompactFlash file system on
Logix5000 controllers.
Who Should Use
This Manual
You should use this manual if you program applications that use
CompactFlash card and RSLogix 5000 programming software with the
following Logix5000 controllers:
•ControlLogix controller
Additional Resources
This table lists Logix products and documentation that may be valuable as you
program your application.
Related Documentation
To view or download these publications, go to:
http://www.literature.rockwellautomation.com.
To obtain a hard copy, contact your Rockwell Automation distributor or sales
representative.
Catalog
Number Title Publication Number
1756-L61,
1756-L62,
1756-L63,
1756-L64,
1756-L60M03SE
Logix5000 Controllers Common Procedures
Programming Manual 1756-PM001
1756-L61,
1756-L62,
1756-L63,
1756-L64,
1756-L60M03SE
Logix5000 General Instruction Set Reference 1756-RM041

Publication LOGIX-AP007B-EN-P - January 2007
6
Notes:

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Chapter 1
CompactFlash Card Enhancements Overview
Introduction
This chapter reviews the enhancements for the CompactFlash file system.
CompactFlash Card
Enhancements
The CompactFlash file system has gone through several enhancements.
•Version 11: The CompactFlash card could only be used for saving
project image files with the NVS feature.
•Version 12: The CompactFlash card stored firmware as well as project
image files.
•Version 16: The CompactFlash card functionality has been extended to
include a file system that can be used for storing tag values, recipes, log
data, and other user data.
The CompactFlash file system as described in this document is available on the
following Logix5000 controllers, with version 16.x or later.
This document explains each feature and provides you with examples that
illustrate how to use those features. After you read and understand this
document and the examples, you will be able to add the CompactFlash file
system functionality to any of your programs.
Topic Page
CompactFlash Card Enhancements 7
Sample File Compatibility 8
CompactFlash File System Features 8
Possible Applications of the CompactFlash File System 9
ControlLogix Controller Version
1756-L6X/A 16.x
1756-L6X/B 16.x
1756-L60M03SE 16.x

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8CompactFlash Card Enhancements Overview
Sample File Compatibility
This document is compatible with the sample projects, version 3.2, dated
January 2007.
•CF_Read_Write_V3_2.ACD
•CF_Read_Write_V3_2_Example.ACD
CompactFlash File System
Features
The file system has the ability to perform a variety of operations to read or
write data to the CompactFlash card. The following are the basic operations:
•Create a file
•Write to a file
•Read from a file
•Delete a file
There is an additional command, verification if a CompactFlash card is
present, but as a user you will not access this, this runs as a background check.
For each of the basic operations of the file system, there are related
functionality.
•Open a file
•Close a file
•Set the file pointer
•Calculate file checksums
•Verify file checksums
•Data parsing
•Error handling
The application code is set up to handle a file up to 4500 bytes in size.
For more information on how to increase file size, refer to Appendix D,
Expand the Code to Support More than 4500 Bytes of Data.

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CompactFlash Card Enhancements Overview 9
Possible Applications of
the CompactFlash File
System
Using RSLogix 5000 software, version 16 or later, and using the application
provided in this publication, you can read and write data to the CompactFlash
card. This could include tag values, recipes, or data log information, just to
name a few.
A possible application would be to store a collection of recipes on the
CompactFlash card. Whenever a recipe needs data, it can be read from a file
on the CompactFlash card. Then if changes were made to the recipe the data
could then be written back to the CompactFlash card for later use.
CompactFlash cards can also be read and written to with a personal computer,
using a CompactFlash card reader. However, using the methods described in
this document, tag values will be written out as binary data to the
CompactFlash card.
Attempting to open the file in a text editor will work, but the contents
displayed will be the ASCII equivalent of the binary data. The application will
not allow for files to be created on a personal computer and then read into the
controller, because checksums are embedded into the data. If you create a file
on the personal computer, it will not have the checksums embedded. When
the data is read it will fail the checksum test.
There are numerous possibilities with this feature, but there are some clear
restrictions that are explained in Chapter 2, CompactFlash File System
Restrictions.

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10 CompactFlash Card Enhancements Overview
Notes:

11 Publication LOGIX-AP007B-EN-P - January 2007
Chapter 2
CompactFlash File System Restrictions
Introduction
This chapter describes the restrictions of the CompactFlash file system.
Restrictions of the File
System
The following are the restrictions of the CompactFlash file system.
Number of Open Files
The total number of open files at one time is one.
Maximum Data Per Message
The maximum amount of data that can be read or written to the
CompactFlash card at one time using the application is 450 bytes, this is
because we are using CIP Generic Messages. Attempts to read or write more
than this amount at one time is not permitted by the application code. If the
code is modified to access more than 450 bytes, the data will not be read or
written to the CompactFlash card. When you need to access more than 450
bytes of data, multiple calls to the file system must be performed and are
handled by the application code.
Removal and Insertion of CompactFlash Card
The application does not support the removal or insertion (RIUP) of the
CompactFlash card when a CompactFlash command is active.
Topic Page
Restrictions of the File System 11
Number of Open Files 11
Maximum Data Per Message 11
Memory Resources and Performance 12
Limited Life 12
Read or Write Portions of a File 12

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12 CompactFlash File System Restrictions
Minimum File Size/Resolution
The minimum file size supported is 450 bytes. If you create a file and write 4
bytes to the file the application will actually write 450 bytes. The same
concepts applies for reads and writes. If you read or write 500 bytes, 900 bytes
will be read or written.
Memory Resources and Performance
The subroutines described in this document depend on messaging to perform
the required operations to the CompactFlash card. These operations use the
same memory resources that might be needed to perform other messaging.
The performance of the CompactFlash card operations will be affected by:
•the communications system overhead time slice and amount of other
messaging or HMI communications that are occurring in the controller.
You can configure the System Overhead Time Slice from the Controller
Properties dialog.
•the task structure of the program. Motion, periodic tasks, or event tasks
slow performance when accessing the CompactFlash card.
Refer to Appendix B, Performance Data for more information.
Controllers Supported
Only the Logix series of controllers support read/write access to the
CompactFlash card using this feature.
Limited Life
Due to the limited life of any CompactFlash card, write to the card only when
necessary. Do not write to the CompactFlash card every program scan. Write
to the card only at predetermined intervals, such as a shift change.
Read or Write Portions of a File
The application code does not support reading or writing to portions of a file
that already exists. Only the entire file can be read or written. If a part of the
file needs to be modified, read the entire file from the CompactFlash card,
make changes, and then write the file back to the card.
Number of Files that Can Be Created
Currently, the application only supports creating files on the root directory.
Because the FAT16 format is used on the CompactFlash card you are limited
to 250 files. This is a Microsoft product limitation.

13 Publication LOGIX-AP007B-EN-P - January 2007
Chapter 3
CompactFlash Commands
Introduction
This chapter describes four of the CompactFlash commands, the ControlFlash
Data Working Tag, and how to determine the number of bytes to read or write.
The file system has the ability to perform a variety of operations to read or
write data to the CompactFlash card. There are four basic commands that you
can access:
•Create a file
•Write to a file
•Read from a file
•Delete a file
There is an additional command, verification if a CompactFlash card is
present, but as a user you will not access this, this runs as a background check.
Topic Page
CF_Data_Working Tag 14
Create Command 15
Write Command 16
Read Command 18
Delete Command 19
Determine the Number of Bytes to Read or Write 19

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14 CompactFlash Commands
CF_Data_Working Tag
Before explaining the four commands, you need to understand the layout of a
key tag in the application. The CF_Data_Working tag, a user-defined data type
tag (UDT), is at the program scope.
This is an example of a user-defined data type tag or UDT.
When a command is executed, the routines use this tag to get all the
information needed to perform the command, such as file name, data, or
number of bytes to read or write. The table below is a layout of the UDT in the
file structure area.

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CompactFlash Commands 15
The UDT tag's type is called CF_File_Structure. This will be important if you
create a Recipe_Manager. The only 3 tags you will need to manipulate in the
UDT are:
•File_Name
The name of the file that will be on the CompactFlash card. This name
can be up to 140 characters in length. The file name must include a file
extension. The .xxx is included in the 140 characters. For example,
testfile1.dat would be an 11-character file name. The format of the
filename follows standard Microsoft file naming conventions.
•Bytes_to_RW
The number of bytes that you want to read or write to a file.
•Data
The SINT array is where you place the data that you want to write or
where data read will be put. The baseline application supports up to
4500 bytes of data, but can easily be expanded.
Refer to Appendix D, Expand the Code to Support More than 4500
Bytes of Data, for more information.
Do not manipulate the other tags. They are used by the routines as they
execute; manipulating them could cause unexpected changes to the file
currently opened.
Create Command
Use the Create command when a file does not exist on the CompactFlash card
and you want to create one. A file must exist on the CompactFlash card before
you can use the other three commands.
The Create command is broken down into four commands:
•Sets the file attribute parameters.
You do not need to manipulate the file attribute parameters.
•Creates the file.
When a Create command is performed, the file is created and then
opened.
•Closes the file.
•Error handling is performed, if needed.

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16 CompactFlash Commands
Set Up the Create Command
To set up the Create command, define the filename including the file
extension, for example, testfile1.dat. To execute the Create command, set the
execute_CF_Create_File bit. The application code resets this bit.
Refer to Chapter 4, Example Application for complete instructions.
Write Command
Use the Write command to write data to the CompactFlash card. A file must
exist on the CompactFlash card before executing this command.
The Write command is broken into 11 commands:
•Data parsing
Only 450 bytes can be written at one time to the file. Therefore, writing
to the file is broken down into 450 byte chunks.
This moves the data into the data_to_write array from the data array in
the CF_Data_Working UDT, putting in the place holders for the
checksums. It also verifies that all arrays used are large enough to handle
the data.
•checksum calculations
This calculates the checksum for each 450 byte chunk of data and places
it into the place holders created in Data parsing.
•The file is open.
•The file pointer is set.
•The data is written.
•The file is closed.
•The file is opened.
•The file is read.
Only 450 bytes can be read at one time from the file. Therefore, reading
from the file is broken down into 450 byte chunks. This moves the data
into the data_read array.

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CompactFlash Commands 17
•The checksums are verified and the data in data_to_write and data_read
are compared to make sure they are equal.
•The file is closed.
•Error handling is performed, if needed.
Set Up the Write Command
To set up the write command, you need to set the bit execute_CF_Write_Data.
The application code handles resetting this bit.
1. Define a file name including a file extension, for example, testfile1.dat.
2. Enter the number of bytes you want to write to the file.
3. Move the data to be written in the CF_Data_Working UDT into the
Data array.
We recommended that you clear the data array before moving the data
into the array. This will clear out any data from previous read or write
commands.
Refer to Chapter 4, Example Application for complete instructions.
TIP If the checksums are not calculated, compared, and
parsed, the file is closed and the write sequence is
restarted from the beginning.
The application will attempt to write a file four times.
After the fourth failure, a checksum error is set.

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18 CompactFlash Commands
Read Command
The Read command is used when you want to read data from the
CompactFlash card. A file must exist on the CompactFlash card before
executing this command.
The read command is broken into six commands:
•The file is open.
•The file pointer is set.
•The file is read.
Only 450 bytes can be read at one time from the file. Therefore, reading
from the file is broken down into 450 byte chunks. This moves the data
into the data_read array.
•The checksums are calculated and compared to those in the file. The
data is then parsed into the Data array in the CF_Data_Working UDT.
•The file is closed.
•Error handling is performed, if needed.
Set Up the Read Command
To set up the read command, you need to set the bit execute_CF_Read_Data.
The application code handles resetting this bit.
1. Define a file name including a file extension, for example, testfile1.dat.
2. Enter the number of bytes you want to read from the file.
3. Move the data from the data array in the CF_Data_Working UDT when
the read is completed.
Only 450 bytes can be read at one time from the file. Therefore, reading
from the file is broken down into 450 byte chunks. This moves the data
into the data_read array.
We recommended that you clear the data array before moving the data
into the array. This will clear out any data from previous read or write
commands.
Refer to Chapter 4, Example Application for complete instructions.
TIP If the checksums are not calculated, compared, and parsed,
the file closes and the read sequence is restarted from the
beginning.
The application will attempt to read the file four times.
After the fourth failure a checksum error is set.

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CompactFlash Commands 19
Delete Command
Use the Delete command when a file needs to be deleted from the
CompactFlash card. A file must exist on the CompactFlash card before you
can use the Delete command.
The delete command consists of two commands:
•Delete the file.
•Error Handling is performed, if needed.
Set Up the Delete Command
To set up the Delete command:
•define a filename including a file extension, for example, testfile1.dat.
•set the bit execute_CF_Delete_File. The application code handles
resetting this bit.
Refer to Chapter 4, Example Application for complete instructions.
Determine the Number of
Bytes to Read or Write
Tags of any data type, including arrays, user-defined types (UDT), and arrays
of UDT tags can be read and written to the CompactFlash card.
When reading and writing data to the CompactFlash card, you need to know
how many bytes are actually being read or written. The following chart
indicates the type and size of the atomic data types. The minimum memory
allocation for a tag is 4 bytes. When you create a tag that stores data that
requires less than four bytes, the controller allocates four bytes, but the data
only fills the part it needs.
For example, if one DINT type tag value is being written to the CompactFlash
card, 4 bytes is the amount of data that will be written. If an array of DINT
tags is being written, the number of bytes being written will be 4 times the size
of the array.
Data Type Bits
31 16 15 8 7 1 0
BOOL Not used 0 or 1
SINT Not used -128…+127
INT Not used -32,768…+32767
DINT -2,147,483,648…+2,147,483,647
REAL -3.40282347E38…-1.17549435E-38 (negative values)
0
1.17549435E-38…3.40282347E38 (positive values)

Publication LOGIX-AP007B-EN-P - January 2007
20 CompactFlash Commands
For example, the tag MYDINTS[100] will be 4 times 100 elements, or 400
bytes of data. Similarly, if a UDT is used, 1 instance of that UDT will be the
sum of the sizes of all the data types within the structure.
The following is a UDT that is the recipe for making waffles.
As you can see, the total size of the recipe is 72 bytes. This means that you
would want to read or write 72 bytes of data to the CompactFlash card. This
would be entered into the Bytes_to_RW element of the CF_File_Structure
UDT.
TIP When reading or writing to the CompactFlash card, it is
best to use UDT tags. This lets you mix different data types
together and lets you know the number of bytes that will
need to be transferred to and from the card.