Entering WIFI Credentials with Morse ;)

The discussion about setting the WIFI credentials is an ongoing one. I came up with an unusual idea. Today I tested and it works. A short introduction:
Loudpeakers generate a magnetic field equal to the sound generated. Many projects contain a relay. This combination is used by me to create a solution to send the WIFI credentials to the Spark :grinning: How to make it happen? Well…look at the pictures:

  1. connect a relay to an analog input. bridge the coil with a capacitor of 180 pF. (This is to filter out HF noise).
  2. Read the analog input with my library.
  3. Create an app that generates binary ‘morse code’ . This app can read the WIFI credentials from your phone.
  4. Place your phone ON the RELAY, as close as you can!
  5. Press the start button.
  6. Wait until the beeps are done.

Here you can see that it works!
This is a photo of the debug output, you can see the information collected by the spark.
It is slow, but it works very good!

If people are interested in the code, let me know, than I will post it here.


These are interesting ideas but I am pretty sure the Electric Imp guys have some patents in this area that keep others from productizing things like this.

I have read their patent which seems to be specifically about optical transmission of setup information, but you would have to hire a patent attorney for an “opinion” about whether or not a method such as you show would infringe their patent or not. I can’t say.

Hi @bko,

I am aware of this, They use light to achieve what they want. But you and I are ‘experienced’ enough in life to know off those little pickup coils we used back in the day to record audio from a telephone earpiece.

This technique is basically the same. Think about audio modems we used in the eighties. And there are hearing aids with magnetic receivers build in ones skull. And what about installations that transmit audio through an induction loop in the ceiling, or floor? So plenty of applications use magnetic fields to transmit data.
I am a strong opponent of patents, and the abuse of them, so after careful consideration I decided to make this idea public. I especially do this because use of this technique is mostly interesting for the makers of non commercial applications, since it’s easy to implement.



Great job here! Is is possible you could send us any code to see the decoding the morse code?

Or any other info we can use?


Hi! has anyone test it ? Can someone share the code :slight_smile: ?
I am interested for the code ! :smile:

HI, @marcus! Any news? Anyone?