EV3 to Spike Prime Bluetooth

[codeadamca]

Hello, I just completed a fresh install of ev3dev. I'm attempting to install "bluepy". But getting all sorts of errors. My end goal is to read bluetooth advertisements from a LEGO Spike Prime device. Has anyone written code to achieve this?

[laurensvalk]

@JorgePe, any ideas?

[JorgePe]

Lots of ideas but not so much results. I've been "documenting" my achievements here:

https://github.com/JorgePe/EV3-Pybricks-Messaging

(as usual it's not fully updated, I remember some minor tweaks I still need to add to the end of this page)

Observing (i.e. read bluetooth BLE advertisements) is very demanding for the EV3, even with a decent USB BLE dongle (my best results were with a CSR chipset, its somewhat old and not so easy to find it these days).

I did try "bluepy" somewhere in my attempts but I can't find anything about it in my notes. Probably because it is one of those libraries that are no longer mantained.

I was about to give up when I found a custom ev3dev image with a more recent kernel and a more recent python. After compilling a more recent bluez I discovered that I could install "bleak" and that gave me some hope (last 6 or 7 years, whenever I google for something related to my own BLE problems, I always find some comment from David Lechner... ev3dev, bleak, pybricks... this man is everywhere :D )

But even "bleak" is evolving and I believe last versions will no longer be possible to use with ev3dev unless someone creates a new image.

So my "ideas":

• try that custom ev3dev image
• use bleak
• don't expect to catch 100% of the broadcasts, start with long duration broadcasts (1 second so ~10 advertisments)*

or...

use something like a Raspberry Pi / Pico / ESP32 as a gateway (BLE to Wi-Fi or BLE to USB). You will sleep much better :D

• with my "setup", when there are no more devices broadcasting in the same channel, ~100% is achievable with a 3-advertisement window so a 300 ms delay is more or less what I expect when sending something from my Technic Hub and detecting it with my overclocked EV3, enough for my initial goal (using EV3 as a text-to-speech companion to my Technic Hub) but not great for real-time control