Jetter JVM-407B-HMI, Руководство пользователя

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230 Jetter AG
10 Programming
If data are to be received via a TCP/IP connection, you can invoke the function
and assign the return value of a variable for further evaluation as follows:
Result := ConnectionReceiveData(hConnection,
Dummy,
Dummy,
ReceiveBuffer,
sizeof (ReceiveBuffer),
T#10s );
When using TCP/IP, data are sent via a previously opened connection.
Therefore, specification of the IP address and IP port is not required any more
and can be ignored in the function.
In the following situations, the task is not processed further after issuing the
command:
 Until the data have been received
 Until an error has occurred
In case of a TCP/IP connection, data are transmitted as data stream.
The device JVM-407B processes this function in the following steps:
Step Description
1
The device JVM-407B waits until data have been received, but no longer
than the specified timeout.
2 If ... ... then ...
the timeout has elapsed or the
connection has been terminated,
the function is exited and an error
message is issued.
data have been received, they are copied to the receiving
buffer given along with the data (but
not exceeding the amount given
along with the data). Then, the
function continues with stage 3.
3 If ... ... then ...
more data have been received than
could have been copied into the
receiving buffer,
these are buffered by the JVM-407B
to be fetched by further function
calls.
4
The function is exited and the number of data, which have been copied
into the receiving buffer, is returned.
If, with a server, data are to be received via a UDP/IP connection, you can
invoke the function and assign the return value of a variable for further
evaluation as follows:
Result := ConnectionReceiveData(hConnection,
IPAddr,
IPPort,
ReceiveBuffer,
sizeof (ReceiveBuffer),
T#10s );
Using this function with
a TCP/IP connection
Functioning principle
with a TCP/IP connection
Using this function with
a UDP/IP server