Fire - Core2 and module Lora

Carles B.

I have an M5Stack Fire and a Core2 and two Lora modules. The idea is to use one to send and the other to receive. The examples LoraSender and LoraReciber are only for M5Stack,
is it possible to use the Lora module between a Fire and a Core2, or can they only be used with the M5Stack?

Thanks in advance
Carles

felmue

Hello @Carles-B

a lot of module have been designed for M5Stack and before M5Core2 came out.

That said most of them can be used with M5Core2, but unfortunately there is no general rule if a given module will work with M5Core2 or not.

Often you'll need to adapt the pin assignment and modify the source code accordingly. Sometimes you'll need to cut a trace on the module board to get around an incompatibility with M5Core2.

What should help you is looking at the schematics of M5Core2 and the desired module to figure out which connections use which GPIO.

A while ago I made a comparison sheet regarding the GPIOs on the M5Stack Bus and M5Core2 Bus - some GPIOs are the same, some have changed position, some are only available on either core.

And lastly there are reports that some modules have mechanical issues (pins too short) to properly fit and make contact with the M5Core2.

So all in all, if a module isn't marked to be compatible with M5Core2 it's probably safe to say that it won't just work out of the box, unfortunately.

Thanks
Felix

felmue

Hello again

I just noticed that the source code for a couple of Modules and Units have been adapted to M5Core2.

Cheers
Felix

Carles B.

Thanks for your information and link @felmue

My initial idea was to buy two TTGO LoRa32 but I preferred these two cores because I saw that they had Lora modules. For the moment I'm going back to the NodeMCU that I find much more comfortable and in a few months I will look at the M5Stack again.

Thank you for your time
Carles

Carles B.

Hello @felmue

If you remove the white board from the Core2 and want to insert the Lora module, the slot is too small and does not fit. You will have to have some modules for the M5Stack, I hope all models are compatible, and other modules for the Core2.

In short if I want to use Lora I have to buy another Fire or similar.

Regards,
Carles

felmue

Hello @Carles-B

I understand you not only have to remove the small white board, but also unscrew and remove the gray bottom plate from M5Core2 in order to attach the module.

Note: Be careful when removing the gray bottom plate as it holds the battery which is connected to the M5Core2 main board.

Thanks
Felix

Carles B.

Hola @felmue

I just saw your photos on the Core2, but I don't think it all fits together. For the moment I leave it on hold, I just installed IUFlow on the Fire and I'm going to practice a bit with it.

Regards,
Carles

felmue

Hello @Carles-B

yeah, I cannot say for sure if the LoRa module would actually fit as I don't have one to try.

Good luck with your experiments and thank you very much for your donation. I appreciate it.

Thanks
Felix

michelepagot

I have both a M5Stack Core2 and Lora868 moduel infront of me right now.
The core module has been disassembled in 2 parts (3 considering the sensor module by removing the 4 screws. To do so I also disconnected the 2 whire battery connection between the battery, sticked to the grey backplane module and the main board. Now the Lora blue module can be connected to the main core board (the white one). It fit perfectly. Now it is the turn of the back plain but I can see at least two problems here:

there's no way to connect the battery back to the mainboard now that the lora module is in between. Maybe I can drill the lora board PCD and sacrifice a couple of empty pcb vias there or add an additional couple of wire segments to go through them.
the battery or the grey plastic frame on the back plain mechanically hit the Lora module metal shield. This second one seems more difficult to fix.

The result is that the backplane cannot be reconnected to the sandwich if the Lora module is in between.

Any idea? Are a couple of photos useful here?