6 F 3 B 0 3 6 2
g.TCP reception processing example (Receive request issued first type)
Ladder program flowchart
TCP reception processing start
Socket status read/verify |
|
| No |
Are bits B and F both 1? | |
(Is a connection established?) |
|
Yes |
|
Is bit 9 set to 0? | No |
(In the state other than RCLOSE?) |
|
Yes |
|
Execute a TCP receive request
(CMD = 0038H).
Hold the input of function block in the on state until the RECV instruction completes.
Instruction completion
Verify the status
Did
the operationNo complete before being
Error result
The processing in this section can be performed at this stage or at the point the instruction terminates abnormally.
A connection has not been established with the specified TCP socket. (Open processing is required.)
The specified TCP socket is:
• Closed by the remote port
(The socket must be closed by the local port.)
Text was not received within the time limit.
timed out?
Yes
Normal complete?
No
An error occurred in reception processing. The specified socket could not receive the data.
Handle the error according to the completion and socket status.
Yes
Terminate TCP reception processing
