2 socket communications flow, Tcp udp – Yaskawa MP920 Communications Module User Manual
Page 181

7.7 Connection with Devices Manufactured by Other Companies
7-35
7
7.7.2
Socket Communications Flow
The following diagram shows the logical programming flow using a socket interface.
TCP
UDP
Note: With the 218IF Module, the sequence in the Master is automatically performed
by the MSG-SND system function, and the sequence in the Slave is automatically
performed by the MSG-RCV system function.
socket
bind
Socket created
Socket created
Connected
IP address and port
No.allocation
IP address and port
No.allocation
connect
Connected
send
Data sending
recv
Data receiving
close
Disconnected
Start
socket
bind
accept
Connection preparations
recv
send
close
Disconnected
Start
listen
Data sending
Data receiving
Connection established
Connection closed
Master
Slave
socket
bind
send to
rev from
Data sending
Data receiving
Data receiving
close
Disconnected
Start
socket
bind
Socket created
Socket created
IP address and port
No. allocation
IP address and port
No. allocation
send to
close
Disconnected
Start
rev from
Data sending
Master
Slve
Connection closed