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Zugriff aus eigenen Anwendungen
11. Access from own applications
In addition to the numerous standardized access possibilities, the Web-IO also
offers the option of accessing from your own application.
This can be done via TCP/IP sockets from the common high-level languages.
However, it is also possible to use common web techniques such as AJAX or PHP
to communicate with the web IO.
Access using TCP/IP sockets
The Web-IO offers three ways to access using TCP/IP sockets:
• Command strings
ASCII
• Binary structures
BINARY
• HTTP requests AJAX
Command strings ASCII
The inputs and counters can be read and the outputs can be set by exchanging
simple command strings.
Depending on the configuration the Web-IO operates in this mode as a TCP server or
UDP peer.
A list of the supported commands and additional details on access via ASCII sockets
can be found in the Web-IO programming manual. (download at http:www.WuT.de).
Follow the manual link on the data sheet page of your Web-IO.
TCP server
To access the Web-IO as a TCP server using ASCII sockets, enable
TCP ASCII-
Sockets
under
Communication paths » Socket-API
. Specify on which server port
the Web-IO should accept connections. The Web-IO can provide up to four TCP
connections on the specified port at the same time. Any additional connection
attempt is rejected.
If the Web-IO does not receive a valid command within 30 seconds, it closes the
connection and is then free for a new connection. The Web-IO behaves in the same
way if an incorrect or unknown command is received.
