Allen-Bradley 1404-M4, User Manual

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Publication 1404-UM001D-EN-E - October 2004
Communications 4-33
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0E hex (14 decimal) = Get_Attribute_Single. Requests a read of
the entire assembly instance defined in the transaction body.
•
10 hex (16 decimal) = Set_Attribute_Single. Writes the data
contained in the message to the assembly instance defined in
the transaction body.
Words 3 through 5 comprise the DeviceNet path: Class, Instance, and
Attribute. For the Powermonitor 3000 data tables, Class = 4, Assembly
Objects; Attribute identifies the data table, and Attribute = 3, data.
Word 6 and following words contain data to write to the
Powermonitor 3000.
Once the message is assembled, your ladder program transfers the
integer file to the scanner module M0 file starting at word 224 (SLC
500) or block transfers the 64-word integer file to the scanner module
(PLC-5).
The ControlLogix controller includes in its instruction set a CIP
Generic message instruction that builds the transaction header and
path from information you enter into the message setup dialog in
RSLogix 5000.
TIP
A convenient way to build Words 0, 1 and 2 is to
multiply the high byte value by 256 and add the low
byte value, using decimal values for each parameter.
Example: TXID = 121; Command = 1. Word 0 =
121*256 + 1 = 30977.
Allen-Bradley HMIs