I recently got a few esp32-c3 superminis and clubbed them together with LLCC68 LoRa modules and was able to successfully setup a lora link between them here and here:
As this was successful, I wanted to turn these into the cheapest and efficient Meshtastic nodes. After some research and building the Meshtastic firmware from scratch for the esp32-c3 supermini module. This is the realization I had about the LLCC68 module for Meshtastic.
Does Meshtastic support LLCC68?
Answer: Yes and No
Yes, if you want a private mesh and No, if you want to join a public mesh
Why?
LLCC68 does not support the default channel “LongFast” the Meshtastic firmware ships with. And because LongFast is the default channel, almost all mesh devices use it and can communicate with each other on that channel which makes (almost) the whole public mesh.
LLCC68 supports most of the preset channels that Meshtastic ships with but not all. And most importantly, does not support the default channel the Meshtastic firmware and thousands of ready built nodes ship with.
Here is a list of channels and modes that are supported
| Channel setting | Alt Channel Name | Data-Rate | SF / Symbols | Coding Rate | Bandwidth | Link Budget |
|---|---|---|---|---|---|---|
| Short Range / Turbo | Short Turbo | 21.88 kbps | 7 / 128 | 4/5 | 500 kHz1 | 140dB |
| Short Range / Fast | Short Fast | 10.94 kbps | 7 / 128 | 4/5 | 250 kHz | 143dB |
| Short Range / Slow | Short Slow | 6.25 kbps | 8 / 256 | 4/5 | 250 kHz | 145.5dB |
| Medium Range / Fast | Medium Fast | 3.52 kbps | 9 / 512 | 4/5 | 250 kHz | 148dB |
| Medium Range / Slow | Medium Slow | 1.95 kbps | 10 / 1024 | 4/5 | 250 kHz | 150.5dB |
Here are the once that are not supported, LongFast being the default thats used almost everywhere.
| Channel setting | Alt Channel Name | Data-Rate | SF / Symbols | Coding Rate | Bandwidth | Link Budget |
|---|---|---|---|---|---|---|
| Long Range / Fast | Long Fast | 1.07 kbps | 11 / 2048 | 4/5 | 250 kHz | 153dB |
| Long Range / Moderate | Long Moderate | 0.34 kbps | 11 / 2048 | 4/8 | 125 kHz | 156dB |
| Long Range / Slow | Long Slow | 0.18 kbps | 12 / 4096 | 4/8 | 125 kHz | 158.5dB |
References:
LLCC68 datasheet: https://www.semtech.com/products/wireless-rf/lora-connect/llcc68
Mestastic Preset and default supported channels: https://meshtastic.org/docs/overview/radio-settings/#presets
So what next?
I will continue to build for LLCC68 for at least the couple of devices I have and make a private mesh to test it just for fun with supported channels and to bring this topic to closure. I will look for some more cheap enough RF modules that do support all the preset channels especially the LongFast mode.
If you have questions, comments, suggestions on this experiment, do let me know what you think in the comments below.
- Does Meshtastic support LLCC68? - 25/04/2025
- Cheapest LoRa Transceiver with the LLCC68 and ESP32‑C3 supermini plus - 10/04/2025
- Pine64 as a DLNA/uPnP Streaming media server for home - 22/01/2020
