RSLogix 5000 to PLC5 DF1 end-device


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I am trying to connect an AB ControlLogix PLC to a Schlagel distributor (for use in a frac sand processing facility). The link will be over serial DF1. However the distributor uses the older style mapping found in PLC5-500 units. I know I can map an array to PLC5 format, so in theory I have a tag (UIO_Array:(X)) which has been mapped across to N7:(X). My concern (I have not actually gone to the facility to implement yet) is communications. I've always worked on local PLCs only, never needing to communicate with end devices. Can someone give me a quick rundown of any important steps I need to know? Thanks in advance?
The "Map PLC/SLC Addresses" feature is only used if the ControlLogix is responding to an external inquiry. So if the Schlagel distributor sends a "Read N7:0, length 10" command, the ControlLogix will replay with the data from ArrayTag[x], Length 10. This works with Integer, Binary, and Floating Point data file types (B, N, and F in the PLC-5) because those are the only ones that are emulated by the Map PLC/SLC Address feature.

If the ControlLogix is initiating the data exchange, that feature is not used. Instead, the MSG instruction includes the remote address in PLC/SLC style, and a local tag in ControlLogix style with the appropriate data type (INT or REAL, usually).

The principal trick to getting an MSG instruction to work with the serial port of a ControlLogix is to know that the Serial Port is considered Port 2. For a point-to-point connection, I always use the CIP Path "2, 1", for Port 2, Node 1.

In a point-to-point DF1 connection, the initiating device is traditionally Node 0, and the target is traditionally Node 1.
That works from the ControlLogix side, but what if you're trying to create a MSG instruction in the PLC 5?

I'm not using point to point but a master slave configuration... so do I use "Remote" settings for the target device? I'm trying to do a write from the PLC5 in the PLC5. Do you know what Remote Bridge Link ID?