btw

My problem is I have an existing btw instruction that is reading data and sending it but when I hit the set up screen I get an error stating that no modules exist in the IO config for this R/G/M. How can this be? Thanks Don.

that message refers to “documentation” for the modules ... NOT to the actual modules themselves ... think of the “documentation” as something like a “label” or a “tag” ...

secret handshake: the system does not need the “documentation” in order to work ... all it needs are the “rack/group/slot” address for the module ... that information is probably already in your processor ...

IMPORTANT ! stop whatever you’re doing and read this post before you make a mess ... you could be heading into some muddy waters if you decide to "add" the module "documentation" to your program ...

and welcome to the forum ...

I've got a pretty good idea that this is a PLC-5 we're talking about...

The I/O config in RSLogix5 is entirely optional. It's quite convenient, but the program will run just fine without it. It just means that block transfers have to be set up by hand just like we used to do it back in the old days with 6200 software.

The good news is, that if you enter the required data into the I/O config, then the setup button will work. When you enter the module in the I/O config (say for example a 1771-IFE) you will get a popup asking for the following information:
BTR Control
BTW Control
Input Data
Output Data

Enter the values from the BTW & BTR instructions, and the setup button should start working.

Good luck,

*DO* follow Ron's advice and read the reccomended thread. You definitely want to answer "Yes" to keep the existing configuration data.

Thanks

Thanks to all, that worked fine. Don