WiFi - Approximate UDP Sending Delay

Materials

  • AmebaD [AMB21 / AMB22 / AMB23 / BW16] x 1

  • Windows computer connected to same network

Example

This example uses Ameba to send UDP packets to a computer and calculates the UDP sending delay.

Ameba Preparation

Open the “CalculateUdpSendDelay” example in “File” → “Examples” → “WiFi” → ” UDP_Calculation ” → “CalculateUdpSendDelay”.

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In the sample code, modify the highlighted section to enter the information required (ssid, password, key index) to connect to your WiFi network.

The server variable also needs to be changed to match the IP address of your computer. You can find the IP address using the “ipconfig” command in a terminal window.

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Computer Preparation

On the computer, Cygwin will be required to compile the code to send the UDP packets. Cygwin can be downloaded from https://www.cygwin.com/

Follow the instructions there to install it. Next, from the “CalculateUdpSendDelay” Arduino example, copy the code from the bottom between “#if 0” and “#endif”, into a new text file and rename the file to “UdpSendDelay.cpp”.

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Next, open a Cygwin terminal, change the working directory to the location of “UdpSendDelay.cpp”, and use the command “g++ UdpSendDelay.cpp -o UdpDelay” to compile the code. A file named “UdpDelay.exe” will be created in the same directory.

Running the Example

First, on the computer, run the UdpDelay.exe file, and the computer will begin to listen for packets from Ameba.

Next, compile and upload the code from the Arduino IDE to Ameba and press the reset button when the upload is complete.

The Ameba will begin to send UDP packets to the computer. Once 10000 packets have been received, the computer will calculate the average delay and print out the result.

It will take some time for 10000 packets to be sent.

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