Allen-Bradley Compact I/O 1769-ADN DeviceNet, Руководство пользователя

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Publication 1769-UM001B-EN-P - October 2002
Explicit Messaging Application Examples B-9
The following correlates the CIP Generic message terminology with
DeviceNet command terminology and illustrates the values needed
specifically for the Get 1769 I/O Configuration Size message:
Should a configuration error occur, the Logix5550 controller’s MSG
instruction will display the error as a hex code as well as in words.
The error code is two bytes, where one byte is the General Error Code
and the other byte is the Extended Error Code.
If the Extended Error Code is 00ff hexadecimal, the responding object
has no additional information to specify. For example, if we make the
third, fourth, fifth, or sixth word of the configuration portion in the Set
I/O Module Configuration command 0 rather than 1862 hexadecimal,
the MSG instruction will set the error bit and display an Error Code of
0009 hexadecimal with an Extended Error Code of 00ff hexadecimal.
The error description is “Parameter error in module configuration”.
Values (Hexadecimal) DeviceNet Terminology CIP Generic Terminology
10 Service
1
Service Code
30c Class 2 Object Type
10 (decimal) Instance
3
Object ID
1a Attribute 4 Object Attribute
8304 First word of the 1769-OF2 configuration file
5
8304 Second word of the 1769-OF2 configuration file 5
1862 Third word of the 1769-OF2 configuration file
5
1862 Fourth word of the 1769-OF2 configuration file 5
1862 Fifth word of the 1769-OF2 configuration file
5
1862 Sixth word of the 1769-OF2 configuration file 5
0000 Seventh word of the 1769-OF2 configuration file
5
0000 Eighth word of the 1769-OF2 configuration file 5
1 Service specifies the type of request being delivered. “10” hexadecimal is a “Single Parameter Write”.
2 Class specifies the desired DeviceNet class. “30c” hexadecimal is the class code for the object representing
1769 I/O.
3 Instance represents the slot number of the I/O module for which we want to set the configuration.
“10” decimal in this example is the analog output module in slot 10.
4 Attribute identifies the specific characteristics of the object towards which the transaction is directed.
“1a” hexadecimal means configuration data.
5 Configuration data is 8 words in length, although only 6 words contain actual configuration data. The last
two words must be included, but must be 0000 hexadecimal. The actual configuration data information may
be found in the Compact I/O Analog Module User Manual , publication 1769-6.0. Chapter 5 of that
publication shows the layout of the six configuration words for the 1769-OF2 module.
The first two words of the configuration file configure channels 0 and 1 respectively for such features as the
output data format (Raw/Proportional Data for this example) and output type (4-20mA for the example).
The next four words are values for the two channels in the event the controlling processor faults or is placed
into the Program mode. For this example, these four values must be in the range of 6241 or 31207 decimal
(1862 to 79E7 hexadecimal), which represents 4-20mA. Any values out of this range will result in a
configuration error.
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