150 Rockwell Automation Publication 5069-UM003B-EN-P - January 2020
Appendix C Programming Example
Figure 65 - Write MSG instruction from a Logix to an SLC or MicroLogix controller example.
Figure 66 - Read MSG instruction from a Logix to an SLC or MicroLogix Controller
Local controller scoped tag 
containing data to be written.
Remote SLC data table address 
into which data will be written.
Path (out serial port) 
to station (222).
Local controller scoped tag into 
which data will be copied.
Path (out serial port) 
to station (222).
Remote SLC data table address 
from which data will be read.