LoRa-E5 firmware update using factory bootloader

Hi,

I want to put my own firmware in LoRa-E5 modules but using the bootloader that comes with the original firmware, but I have found exactly zero information about how thas bootloader works. Am I missing something?

You may be wondering why I don’t just use an ST-Link. Well, I have a number of deployed devices in which I use the AT command interface from another microcontroller, and I’d like to do the upgrade from that microcontroller, which can be done remotely without even opening the enclosure. I designed these devices so the microcontroller can put the module in bootloader mode, but I don’t know how to create the firmware update binary nor how to upload it to the bootloader.

I’m not sure about why Seeedstudio is kind of secretive about the factory firmware, but as far as I know, allowing to replace that firmware using their bootloader shouldn’t pose any risk to the factory firmware, should it?

Thanks.

You make any progress on this I would like to do something similar!?