Ladder Logic - Rslogix Version 15 And Lower - ProSoft MVI56E-MCMR User Manual

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User Manual

6.8.6 Ladder Logic - RSLogix Version 15 and Lower

MSG_BLKS
The MSG_BLKS routine passes data between the module and the ControlLogix
processor using MSG instructions. Data transferred using these blocks is of low-
priority and completely under control of the ladder logic.
The first rung requests the module's error/status data:
The following illustration shows the format of the MSG block.
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MVI56E-MCMR ♦ ControlLogix Platform
Modbus Communication Module with Reduced Data Block
ProSoft Technology, Inc.