rf95modem-go

README

rf95modem-go

Golang library to send and receive data over LoRa via a serial connection to a rf95modem.

This library was tested against the rf95modem commit acf3721, informally version 0.5.1.

Library

The primary focus of this library is the sending and receiving of data via LoRa. An io.Reader and io.Writer are provided for this purpose. It is also possible to register handler functions for incoming messages. Furthermore, both frequency and modem mode can be changed. For more information take a look at the documentation.

package main

import (
	"fmt"

	"github.com/dtn7/rf95modem-go/rf95"
)

func main() {
	modem, modemErr := rf95.OpenSerial("/dev/ttyUSB0")
	if modemErr != nil {
		panic(modemErr)
	}

	if _, err := modem.Write([]byte("hello world")); err != nil {
		panic(err)
	}

	buf := make([]byte, 64)
	if _, err := modem.Read(buf); err != nil {
		panic(err)
	} else {
		fmt.Printf("%x\n", buf)
	}

	if err := modem.Close(); err != nil {
		panic(err)
	}
}

Example: rf95logger

A simple logger script for incoming messages with their RSSI and SNR.

$ go build ./cmd/rf95logger

# Logging messages from /dev/ttyUSB0 at 868.1 MHz on mode 1, fast+short range
$ ./rf95logger /dev/ttyUSB0 868.1 1 | tee loralog.csv

Example: rf95pty

A small proof of concept is rf95pty to bind a rf95modem to a new pseudoterminal device. This code should work for POSIX operating systems.

$ go build ./cmd/rf95pty

# Node A provides a shell over LoRa - stupid idea, btw

$ ./rf95pty /dev/ttyUSB0
Starting modem with Status(...)
Opening pty device /dev/pts/5

$ socat /dev/pts/5,raw,nonblock,echo=0 exec:sh,pty,stderr,setsid,sigint,sane

# Node B uses this shell

$ ./rf95pty /dev/ttyUSB1
Starting modem with Status(...)
Opening pty device /dev/pts/7

$ screen /dev/pts/7