Hello,
two of our devices ( which are using EG912Y modem) have some problems related to UDP datagram sending.
Our code sends the following command to the modem..
AT+QIOPEN=1,1,“UDP”,[IP],5052,0,0
..but the modem does not respond to this command, so it exceeds the 150s maximu timeout described in the at tcp manual.
This beaviour is not always the same: seems to depend by the device position (is mounted on a moving car).
The FW version is EG912YEUAAR01A08M16_01.001.01.001
We would like to understand more about this behavior. What are the cases in which an UDP datagram transmission takes so much..simply Opening the connection (I cannot call QISend if QIOpen does not return)? An UDP , unlike TCP, does not need an ack..so I expect that sending UDP is always a successfull and fast operation.
Thanks for your time.
in order to activate the context we actually use the AT+CGDCONT (activate PDP context). What is the difference using QICSGP instead?
What do you think could be the motivation for the
answer delay (exceeds the 150 seconds)? It seems to be related to using two concurrent connections (existing transparent TCP connection + QIOPEN on UDP). Another aspect that seems to be involved is the work place: the problem happens when the device is positioned in crowded places (=high cell load). Any suggestions?
