As part of a little research and also some fun I decided to try my hand at seeing how small of an ESP32 board I can make with functioning WiFi.
If you add another GPIO and make a silicone mold you could make an in-cable eavesdropper on USB connections that streams out the data via the wifi. That would be a pretty scary tool in the right circumstances.
These cables can be bought for like $200 mostly legally.
This is a very cool experiment, even if the board doesn't end up being that practical (the antenna hack is going to be an ongoing issue I think) your documentation looks great at a glance!
Thank you! I agree, antenna definitely needs some improvement.
Really cool. I just ran into a situation where it would be handy to have a small Bluetooth device that plugs into USB-C. However soldering something like this seems a bit beyond me, is there a more turnkey solution?
If it is a little bigger to incorporate a bigger chip antenna and some GPIO pins, it is going to be very useful for a lot of IoT projects!!
The XIAO series of ESP32s is exactly that.
They are 4x the size though, almost exactly double in both length and width.
there is plenty of those already and not all too hard to make yourself, see LilyGo T01-C3
Its of format of original ESP8 so you get serial + 3 IO pins
Definitely would be more functional with more of the GPIOs exposed.
If you want an ESP32 dev board with GPIOs exposed there are dozens (or hundreds, maybe thousands) of other options out there. It makes sense not to expose them when you're going for the smallest possible footprint.
Nice work, kudos!
01005? Oh no no no. I can barely do 0402s by hand and those are _2.5x_ larger.
With one of those mini-hotplates for reflow soldering and a LCD microscope it's still fairly doable.
FWIW, there's a step by step soldering guide in the readme:
https://github.com/PegorK/f32#building-the-f32
It looks doable, but of course a lot of carefulling is required when placing the components.
> PCBWay does also offer assembly services
Seriously? For a tiny board like this also? Genuine question.
yes, but they use a machine, they don't do it by hand.
> This can be seen in my highly necessary depiction below.
I love this. Fun and insightful article. Thank you.
Thanks for checking it out!