Pulseroller ConveyLinx-Ai2 - Module Vs. Assembled Address with MSG Instructions; Message Configuration for Reading from Ai2 Module Registers

Publication ERSC-1521 Rev 1.0 – February 2019
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Connecting to Rockwell PLCs
MODULE VS. ASSEMBLED ADDRESS WITH MSG INSTRUCTIONS
What this means is that there are certain restrictions on what you can do with MSG instructions with an Ai2 module.
Here is a list:
• You can us a single MSG instruction to read one and up to 30 consecutive Module Modbus registers
• You can use a single MSG instruction to write to one (an only one) of the Module Modbus registers
• You can use a single MSG instruction to read any of the available Assembled Input registers in their entirety
• You CANNOT use any MSG instruction to write to any Assembled Output registers.
MESSAGE CONFIGURATION FOR READING FROM AI2 MODULE REGISTERS
Read MSG Setup
• Select “CIP Generic” as the
Message Type
• Select “Get Attribute Single” as
the Service Type
• Class is always set to 64
• Instance is the Module Modbus
register address. In this example
the Instance is 88 indicating
register 4:0088
• Attribute is the number of
registers to read. In this
example it is set = 2. This means
the MSG instruction will read
Module Modbus registers 4:0088
and 4:0089
• Destination Element is the user
defined tag for the MSG
instruction to place the data it
reads from the Ai2. In this
example, “TempDiagStatus” is
the user defined tag.
The acceptable values for Attribute are from 0x1 to 0x1E which is 1 to 30 contiguous registers. In the above example,
the data being read is Module Status #1 and Module Status #2 registers (4:0088 and 4:0089). This same MSG
instruction could be duplicated for each Ai2 in ZPA mode in a given conveyor system and used to populate an array
of module status data that could in turn be used for example to feed an HMI diagnostic application.