NPorts do not modify or manipulate the data segments of the serial frames passing through their serial ports. The serial stream is just segmented into different Ethernet packets for the purpose of time efficiency.
To create your own data segmentation rules, enable the Data Packing function in your NPort’s web UI. There are three methods to pack your data—Delimiter, packet Length, and force transit. Choose a method that fits your application and the serial data will be packed into the Ethernet packet as per your requirement. For more details on implementing data packing, refer to your NPort’s User Manual.