Rockwell Automation 1756-DHRIO_DHRIOXT ControlLogix Data Highway Plus-Remote I/O Communication Interface Module - Manual (Page 167)

Rockwell Automation Publication 1756-UM514C-EN-P - June 2014 167
Application Guidelines and Tips Appendix B
Increase Unconnected Message Buffer Configuration
Configure the message as shown below
Increase Unconnected Message Buffer Source Data
The source array tag needs to have data manually placed into some of the
locations. Set element #4 to the value desired of the UCB. The other values
cannot
be varied. The dialog box is shown below.