Communication Type Of Protocols - Mitsubishi Electric MELSEC-L SERIES Basic User Manual

11.2

Communication Type of Protocols

Receive and send packets from/to the connected device for the process execution are registered in a protocol. Packet
elements set using the predefined protocol support function correspond to the data part of the send/receive packets.
The following shows an example of packet configuration. For details on the packet elements, refer to Page 346,
Appendix 8.3.
(1) TCP/IP
Destination Sender's MAC
MAC address: address:
6 bytes 6 bytes
Ethernet header
(2) UDP/IP
Destination Sender's
MAC address: MAC address:
6 bytes 6 bytes
Ethernet header
Communications with the connected device using the predefined protocol function are performed with the
following procedure (communication types).
For the operations of each communication type, refer to Page 339, Appendix 8.1.
Communication type name
Send Only
Receive Only
Send&Receive
100
Maximum data length: 1514 bytes
Header
Type: IP: TCP:
2 bytes 20 bytes 20 bytes
TCP/IP header
Maximum data length: 1514 bytes
Header
Type: IP: UDP:
2 bytes 20 bytes 8 bytes
UDP/IP header
Sends a send packet once.
Receives a packet if it matches any of up to 16 defined receive packets.
Sends a send packet, then receives a packet if it matches any of up to 16 defined
receive packets.
Data
40 to 1500 bytes
Data
28 to 1500 bytes
Description