Rockwell Automation Allen-Bradley DriveLogix 5730, Руководство пользователя

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Communicating with Devices on an DeviceNet Link 8-7
Mapping starts at word 0 for both the input and the output data image. The
input status and output configuration words are no longer included with the
I/O data scanlist. Use the status and configuration tags created in RSLogix
5000 software to read status or set configuration bits.
Transferring Data
There are 28 bytes of input data and 6 bytes of output data for this example.
The I/O modules in the adapter’s system are:
The total is 7 DINT words or 28 input bytes. The first DINT word is adapter
status, leaving 6 DINT words (24 bytes) for data. The input data maps to the
controller’s input data tag at the following word locations:
The output data can be determined in a similar manner. This data begins
with word 0 of the output tag in the controller as follows:
TIP: The input and output data being exchanged by the scanner and
adapter is packed data. This means that there is no special structure to it that
makes it obvious which I/O module it is associated with.
To establish which data is from which module, you must list the number of
input and output words each module has. Then, based on its position in the
I/O bank, you can determine where any module’s data is in the controller’s
I/O tags.
Module Input Output
ADN Status Information
(added by the 1769-ADN) 1 DINT word 0 words
1769-IA16 1/2 DINT word 0 words
1769-OB16 1/2 DINT word 1/2 DINT word
1769-IF4 3 DINT words 0 words
1769-OF2 2 DINT words 1 DINT word
Total Words 7 DINT words 1 1/2 DINT words
Total Bytes 28 bytes 6 bytes
Location Description
Word 0 1769-ADN status information
Word 1 1769-IA16 module’s input word
Word 1 1769-OB16 module’s input data (output data echo)
Words 2-4 1769-IF4 module’s input data
Words 5-6 1769-OF2 module’s input data
Location Description
Word 0 1769-OB16 module’s output word
Words 0-1 1769-OF2 module’s output words