Porting Guide to new hardware

tc61 · January 4, 2021, 12:17pm

Hello, I happily stumbled on this project a few weeks after starting to build something very similar.

My DIY project is inspired by a commercial product by GoTenna, which is also very similar.
I would like to know if it is possible to port meshtasitc (firmware+app) to my own hardware setup ?

My hardware setup is also based on ESP32 and the LORA is from EBYTE (based on SX1872) and no GPS (keeping the BOM cost down, i dont think there is a need to duplicate the GPS function in the smartphone) ? can you explain the need/benefit of having a separate GPS ?

The other difference is that I added a walkie talkie module to add PTT capability.

If it is possible to use meshtastic as baseline ? is there a porting guide ?

Thanks…

geeksville · January 5, 2021, 2:07am

hi @tc61,

that sounds like a pretty quick port probably. A few things might help:

this (big) thread about porting to new hardware: Building for NRF52 boards (kinda unstructured, but might be worth skimming)
in short you mostly need to just add an entry to platformio.ini and configuration.h (to assign gpios). See here for a recent board that did this: https://github.com/meshtastic/Meshtastic-device/commit/5595fb38c1464804c2efbf164755c9172190b1ea
all of the hardware you listed is already supported so I think 95% of the work is just configuration.h
if you have questions/problems post either here or in the developer slack channel and I’m sure someone will help.

re: walkie talkie
I bet that could be added nicely using the (young so you might find bugs?) plugin api. You’d define a new port number for ‘voice’ and send those packets when the user sends.

re: gps
gps is optional, if the device doesn’t have one the android app will auto fill-in (using the same protocol). But the reason I’m a fan:

I wanted weeklong runtime with location data for nodes. The gps (+ heavier CPU) in the phone burns a lot of current in that case.
Every node having high quality time will eventually allow us to save more power by leaving even lora receivers sleeping most of the time, and turning on briefly to see if anyone in the mesh wants to send something. (That said, for nodes without a phone or a built in GPS, they will use (less good but not horrible) network time (as long as at least one node in the mesh has a GPS or phone).
really cheap now adays

tc61 · January 5, 2021, 2:52am

thanks for the quick response…

my approach (not very far) is using ESP32-A1S (audio) and using BLE (for data) and phone BT HFP(or HSP) for voice

and ESP32 as AG and route the voice to walkie talkie module

(via I2S convert to MIC/SPKR), do you see issue (or are you suggesting a different approach ?)

(have yet to see if two radio module can co-exist side by side ??)

i am also planning to try a DMR (single module, instead of one LORA and one WALKIETALKIE module), but DMR module is quite expensive

as for GPS, i was thinking about that after posting the question, i can see two use cases for that… one as “BREAD CRUMB”… ie if someone is going

on a long trip, he may possibly drop a NODE along the way as repeater, and then that GPS position can be used to COLLECT these CRUMBs on the

way back… (that can possibly extend the range to many miles)

also, another possibilty is to use a small DRONE or a ballon (POOR MAN’s STARLINK :0 ) having a node/repeater in the sky (good line of sight!)