Unetstack C API with Unetsim simulator

Question

I am trying to run the C API for Unetstack. I have been trying to run the test code here.

I am running 3-node-network.groovy from the unetsim-1.4 sample code in my terminal to use as my modem network. I am using unetsim-1.4a for linux for my simulator.

This is how I call the test code:

make IP="127.0.0.1" ADDR=1 test

The test code is able to open the modem, but is not able to send packets through. This is the error I end up getting:

Packet transmission: FAILED
Packet transmission: FAILED

Segmentation fault (core dumped)

and I do not see any received packets on my simulator shell.

When I run the 3-node-network.groovy simulation with the Python API, everything works fine, and I can see packets being received on my simulator shell.

How should I set up the environment to run the Unetstack C API test code to transmit and receive through a simulated modem network on unetsim?

Answer 1

Follow the steps below to set up the environment to test basic modem operations using UnetStack C API with simulated modem network on unetsim :

1. Run 3-node-network.groovy from unetsim-1.4 sample code which creates a simulation environment with 3 nodes deployed as shown below for example:

   bin/unet samples/rt/3-node-network.groovy

2. Change the port number from 1100 to 1101 at this line in the code in your unet-contrib local repository.

3. Set the destination address to 2 at this line.

4. Set the carrier frequency to 25000 Hz at this line.

5. Navigate to this folder in your unet-contrib local repository and perform the following steps: make c c/examples localhost

You should be able to see successful transmissions from node 1 and corresponding receptions on node 2.