amodem VS RadioHead

This will get you started:

Tony Fisher wrote V.32 soft modem stack for SGI Indy back in 1996. York University couldnt handle hosting whole 8 megabytes of his stuff https://www.cs.york.ac.uk/news/fisher/home-page but at least they had the decency to upload it to github instead of just deleting https://github.com/university-of-york/cs-www-users-fisher/tr... Randy Rossi rewrote this project and got working V.21/23 https://github.com/randyrossi/fisher-modem

Fabrice Bellard, because of course he did :), implemented his own version all the way to V.34 with parts of V.90 https://bellard.org/linmodem/

V.21 modem implemented in Gnu Radio https://web.archive.org/web/20170627151353/http://aaronscher...

amodem - good source of ready made modulation implementations https://github.com/romanz/amodem

minimodem- simple radio link FSK modem https://github.com/kamalmostafa/minimodem

audsl - leased line project, not compatible with standard modems https://www.araneus.fi/audsl/ but might give some ideas.

This one is excellent, you can transmit and receive data as audio OFDM : https://github.com/romanz/amodem You will probably need to pipe it to a modulator for RF transmission.

https://github.com/romanz/amodem is the tool i used to wrap netcat data into.

You need to "encode" it in some way; https://github.com/romanz/amodem can help.

//Transmitter code /* Reference: https://lastminuteengineers.com/433mhz-rf-wireless-arduino-tutorial/ http://www.airspayce.com/mikem/arduino/RadioHead/ */ #include #include // Not actually used but needed to compile RH_ASK driver; char xData[32] = ""; char yData[32] = ""; String msgX, msgY; void setup() { Serial.begin(9600);  // Debugging only if (!driver.init()) Serial.println("init failed"); } void loop() { // for debugging int xAxis = analogRead(A1);  // Read Joysticks X-axis int yAxis = analogRead(A0);  // Read Joysticks Y-axis Serial.print("X-axis: "); Serial.print(xAxis); Serial.print("\n"); Serial.print("Y-axis: "); Serial.println(yAxis); Serial.print("\n\n");   msgX = analogRead(A1);   msgY = analogRead(A0);   // X value msgX.toCharArray(xData,5); driver.send((uint8_t *)xData, strlen(xData)); driver.waitPacketSent(); delay(10);   // Y value msgY.toCharArray(xData,5); driver.send(yData, strlen(xData)); driver.waitPacketSent(); Serial.println(xData); delay(1000); }

If you do not use WiFi (though I would) and have to fall back to 433Mhz or similar RF signalling then look at the Radiohead library rather than reinventing the wheel.

These 433 style boards are the ones I would look at (range being a possible limit) - maybe using the RadioHead library and front end the Pi with a dedicated receiver board if you cannot find a compatible Pi library.

You need a networking stack. There are some good examples out there; I remember the RadioHead library from years back. I think someone said it sucks and use this other thing instead but I can't remember what the other thing was. You'd write a driver that performs modulation with the HackRF, then use the rest of the stack to do the packetizing and retransmission and stuff.

As mentioned, chirpstack works well if you still want to use LoRaWAN. Alternatively, you can use a system such as https://www.mysensors.org/ which builds its own protocol on top of lora. Finally, you can write everything from scratch using radio libraries (eg: https://www.airspayce.com/mikem/arduino/RadioHead/)

I have a project where I use LORA with the Radiohead-library (http://www.airspayce.com/mikem/arduino/RadioHead/) to gather data from various locations, and then publish that to the web.

I would take a look at https://www.airspayce.com/mikem/arduino/RadioHead/. I have not personally used this and it is not free for commercial use, but it is one option for providing higher level network functions.

You also need to determine if there is any kind of a conflict between these various packages you are using such as a pin number, etc. See RH_RF69 send hang due to waitPacketSent failed · Issue #12 · PaulStoffregen/RadioHead (github.com) So you need to be able to do testing with status messages to Serial so that you can see those logs.