This here is an ESP8266.
It's a little three dollar computer, all in one chip with wifi!
That's just insane.
The entire module, the whole thing here is available for about $3.
And up until April 1st, it did not have any way to connect by any way other than wifi.
But, I figured out a way to connect it up to Ethernet.
So, now it can have wired ethernet instead of wireless ethernet.
And, you might be wondering why would you want to do that, or how even?
The how is addressed inside the Hackaday article linked below or in the video that's - you
know - you can click on up there.
The why is a little bit, to me very clear - but may not be obvious.
Though it has a wifi chip, and you can connect to wifi networks using that, sometimes you
might want to do something with that wifi chip other than connect to a network.
With 802.11, the wifi standard that everybody uses, packets are generally flung around from
every device.
A device like my cell phone right here, which is uuh, configured in wifi teather mode is
now telling everyone "Hey!
I'm Charles' cell phone!
I have internet!"
And, Will's AP up there on the ceiling is saying "Hey I have internet, here is my name.
And every device all around says all sorts of information about itself and anyone can
listen, anyone who's tuned to the channel, even the ESP can hear it.
The difference is now, we can get the data off in a meaningful way.
So, I have the ESP here, hooked up and powered by this little power brick thing here.
It's not hooked up to my computer or anything, and over here, I have a webpage.
So, this is just like the other websockets webpages I've been using and right now, I'm
tuned to Channel 8 and I can see uuh.
This looks like my cell phone right there.
I can recognize the MAC address.
A MAC address is a unique identifier for all devices.
I can see the last time I saw a packet with it is consistently less than a tenth of a
second, and I can see that the signal coming from it is relatively strong.
I mean, after all, my cell phone is right there and the ESP is right there.
Anyway, in this website, I can actually browse that.
I can switch the channel back to say channel 1 and I can see all the other channels.
I'm actually connected to the ESP through this webpage here through an access point
in the ceiling into this houses' internal lan, out that switch and into the ESP.
So, it's really a convenient way of connecting the ESP to a network so you don't hae to worry
about connecting to wifi or anything else if you don't want.
Right now, let's switch back to Channel 8.
Surely I can get this to go.
As you'll see the, the amount of time since it's seen these access points and pieces of
hardware - many of them I don't recognize they could be neighbors' devices or anything
else - go away.
Now, all that I'm left with, mostly is my cell phone.
But you might be wondering "How do I KNOW that it's my cell phone?"
Well, as it turns out, you can actually, with Wireshark, connect to the ESP8266.
So, the ESP8266's address is 10.1.10.5, port 6648.
Netcat says "make a TCP connection to this address" on that port and use this symbol,
a pipe to pipe it into wireshark.
When you give wireshark these parameters dash k dash i dash.
It puts wireshark into a mode where it can just simply capture the packets straight from
what we call standard in.
So right now, this is just all the pactet captures coming from the ESP8266.
So, as you can see, there's just one packet after another after another coming from my
cell phone.
Yes, we can see my cell phone's name is "phone."
I know that's original.
You can see all these packets of it saying "Hey, I'm here" "Hey, I'm here" "Hey, I'm
here" and it's really cool that espressif has given us limited access to the wifi in
this way.
I say limited because it doesn't give us complete access to all of these packets.
Unfortunately it is a little bit limited in so far as the size of the data we can receive.
So, these beacon packets are fairly large, they're a hundred or two hundred nineteen
bytes wide, the ESP can only capture the first hundred bytes or so of it.
So, you can see here, that whoah, that here's all the data in the packet.
These are little messages that were sent on the air.
And unfortunately, right around here somewhere, there, it cuts off and we have to send zeroes
because I don't know what data's there because it's not being passed to me.
At any rate, all of this is a system by which you can turn any ESP8266, like that one there,
into a remote listening station for wifi signals and plug them into a network and take that
data and send it back to a central hub, or, whatever else you wanted to view the data
on.
I could even view it on my cell phone.
I hope you guys liked this video and it just goes to show another thing you can do with
the ESP8266 now that it can talk Ethernet.
So, once again I'd like to encourage everybody if they'd like to understand how this is working
to read the hackaday article, my github code is posted here.
So, anyway, yeah.
I hope you guys like it who knows - maybe someone will expand upon it or improve the
packet API, I don't know, there's a lot of places this could go and a lot more reliability
there could be.
"You gonna work?"
"Gonna work?"
"Huh?"
Hey!
It linked!
There is one big thing I need to mention about this project, I am still having some reliability,
link reliability issues, with both products, both the one that's raw and the one that's
hooked onto the board.
I don't really know what's wrong with them but I haven't sepent that that log debugging
them.
So, if it doesn't link at first, you might have to try again.
I'm not really sure why.