ELS61 EHS5 UDP differences | Telit Cinterion IoT Developer Community
July 22, 2021 - 11:47am, 2194 views
we are migrating with our app from a device with EHS5 module to a device with ELS61 module.
Now we have an issue:
Sending UDP datagrams does not work like before.
Are there differences between this two modules? Maybe in the connection string.
Actually we use "datagram://udpIp:udpPort".
In general there are differences between EHS5 and ELS61 Java APIs. In regard to UDP specifically, in ELS61 we expanded our API with new DatagramReader/DatagramWriter classes and SecureDatagramConnection interface. However, if you based your application only on the elements available in both EHS5 and ELS61 then the same source code should work on both of those modules - assuming that the respective MIDlets were built with the correct WTKs. The connection string also seems correct.
Could you explain in more details what you mean by saying that sending UDP datagrams works differently on ELS61? Do you get some Exception? Also, which WTK do you use to build your MIDlet for ELS61 module?
actual we use a WTK with the version 01.132 from 09.02.2018.
I also tried the WTK version from the old Module ( 03.510 from 13.04.2018 ).
Maybe you cold provide us with a actual WTK, and a short example for sending a UDP Datagram.
I do not get some Exceptions. Its just not working as on the other module.
I see. Could you share your module's response to ATI1 command to check what firmware version is installed on it? I'll then share the appropriate WTK and sample code with you via email.
sorry for the very long delay. This is the anwser for the ATI1 Command.
I've sent you an email. Please test the SDK. In case you have still issues with UDP please share the code you use for sending and the log what happens.
i detect the problem. The UDP connection is an own UDP logger. If i open the a new udp connection, the udp data send to my server. An other thread hold an tcp connection, thats not working now and an exception thrown. Now the tcp thread reconnect and now the udp connection catch an exception. Can the modem only handle one connection.
Is this problem related to SDK I sent you or is it general?
It is possible to open and use multiple connections (TCP/UDP sockets) at the same time. So I suppose that there may be an issue in your application. What kind of exception do you get?
The thread that you linked is about multiple PDP context to the same APN which is a kind of internet gateway for your apps. And the network may only allow one. But usually you only need one for your data traffic.
the keyword "the same APN" was the solution. Currently my first connection use a correct connection string with apn settings. The second connection string use only ip + port. Older versions of modem working with this procedere.
I extend / complete the second connection string with apn settings and now its working.
Thank you for the feedback.
It's better to explicitly set APN for all the connections to be sure that all are set up in the same way with the same PDP context.