This page explains how to set up the development environment and create applications for Econais.
When a new TCP/IP session initiated on the Econais EC19D board, it always starts from port 49153 and a SYN packet does not have the tsval tcp option value. So, on the next time when the Econais board is restarted, it sends the first same SYN packet which will be treated as re-transmission by the TCP stack of the server. The following wireshark dump illustrates the problem.
The server treats this SYN packets drop as re-transmitted, therefore a new connection can't be established until the timeout expires and a new source port is chosen.
Use a random source port on the new connection opening:
|To open a new TCP/IP session on the Econais board, use randomly generated source ports.|
To build a sample application for Econais, at first you need to set up the development environment as described in the official “Econais programming guide.”
After the development environment setup is finished, proceed as follows:
Download an archive with a Kaa sample application and untar it.
$ cd /path_to_the_folder_with_the_archive $ tar xf./archive_with_application.tar.gz
Set the ECONAIS_HOME_VAR environment variable.
$ export ECONAIS_HOME_VAR=/path_to_the_econains_root_folder
where path_to_the_econains_root_folder is the path to the econais folder which is referenced in the Econais programming guide as <root>.
Go into the directory with the Kaa sample application and run the deploy.sh script.
The script will create the folder with all necessary files inside the <root>/applications folder.
$ cd KaaSampleApplication $ ./deploy.sh
Go into the <root> folder and run the following make command.
$ cd <root> $ make SDK_APP=KaaSampleApplication