Specify Slc Messages; Specify Block-Transfer Messages - Allen-Bradley Logix5000 Reference Manual

Specify SLC Messages

Use the SLC message types to communicate with SLC and MicroLogix
controllers. The following table shows which data types that the instruction lets
you access. The table also shows the corresponding Logix5000 data type.
For this SLC or MicroLogix data type
F
L (MicroLogix 1200 and 1500 controllers)
N

Specify Block-transfer Messages

The block-transfer message types are used to communicate with block-transfer
modules over a Universal Remote I/O network.
If you want to
Read data from a block-transfer module
This message type replaces the BTR instruction
Write data to a block-transfer module
This message type replaces the BTW instruction
To configure a block-transfer message, follow these guidelines:
·The source (for BTW) and destination (for BTR) tags must be large
enough to accept the requested data, except for MESSAGE, AXIS, and
MODULE structures.
·Specify how many 16-bit integers (INT) to send or receive. You can
specify from 0...64 integers.
If you want the
Block-transfer module to determine how many 16-bit
integers to send (BTR)
Controller to send 64 integers (BTW)
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Input/Output Instructions (MSG, GSV, SSV, IOT)
Use this Logix5000 data type
REAL
DINT
INT
Select this command
Block-Transfer Read
Block-Transfer Write
Then specify
0 for the number of elements
Chapter 4
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