Rockwell Automation 1775-KA PLC-3 Communication Adapter Module User Manual - Manual (Page 127)

Full-Duplex Protocol
Chapter 10
10Ć23
Embedded Response Option
To simplify the design of the receiver in some cases, you can disable
transmission of embedded responses by turning off the embedded
response switch. If you turn this switch off, the 1775–KA module’s
multiplexer cannot embed response codes while sending a message.
Instead,it delays sending response codes until after it sends the next DLE
ETX BCC sequence.