Omron sysmac NX102-9 Series Owner's Manual page 350

9 Socket Service
Additional Information
If TCP is used to send data to a different segment, the data is separated into 536-byte frag-
ments.
Using UDP
The conditions shown in the following figure occur when data is sent in fragments in UDP communica-
tions.
(1) A send request is sent from the user program at the sending node. It specifies a vari-
able with a data length of 2,000 bytes.
(2) The built-in EtherNet/IP port separates the send data into 1,472 bytes in data A and
528 bytes in data B.
(3) Data A and data B are sent in sequence by the sending node.
(4) Data A and data B are joined to restore the original send data, and the data is passed
to the user program.
Sending node (Controller)
User program
(1) Send request
2,000 bytes
Original data
Because UDP communications are performed in datagram units as shown above, send data is
returned to the original data format before it is passed to the user program.
9-6
Built-in
EtherNet/IP port
Ethernet line
(3)
(2) Fragmenting
Data A and
data B are
1,472 bytes
separated
and sent.
Data A
Data B
528 bytes
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User's Manual (W506)
Receiving node (host computer)
User program
Receiving node
(4) Receive request
2,000 bytes
Data A Data B