DStarRepeater

A D-Star digital voice repeater controller for homebrew amateur radio hardware. DStarRepeater interfaces with ircDDBGateway or DStarGateway to provide D-Star networking — callsign routing, reflector linking, and ircDDB.

This is a headless CLI daemon written in portable C++17 with no GUI dependencies. It runs on Linux (x86_64, ARM/Raspberry Pi), Windows, and macOS, and has been tested on Ubuntu 24.04, Debian Trixie, and Alpine 3.21.

Supported Hardware

Modem	Interface
DVAP Dongle	USB serial
DV-Mega	USB serial
GMSK Modem (Dutch*STAR, DUTCH-UHF)	USB (libusb)
Sound Card / UDRC	ALSA (Linux), PortAudio (Windows/macOS)
MMDVM	USB serial
DV-RPTR V1, V2, V3	USB serial or network
Icom Terminal / Access Point Mode	USB serial
Split (multi-receiver)	UDP network

Quick Start

1. Install dependencies

Ubuntu / Debian:

sudo apt-get install g++ make libasound2-dev libusb-1.0-0-dev libmosquitto-dev

Raspberry Pi (Raspberry Pi OS / Debian):

sudo apt-get install g++ make libasound2-dev libusb-1.0-0-dev libmosquitto-dev wiringpi

Alpine Linux:

apk add g++ make alsa-lib-dev libusb-dev linux-headers mosquitto-dev

Windows and macOS — see the platform-specific notes below.

2. Build

make

3. Configure

Copy the example config and edit for your hardware:

sudo cp /etc/dstarrepeater/dstarrepeater.ini.example /etc/dstarrepeater/dstarrepeater.ini
sudo nano /etc/dstarrepeater/dstarrepeater.ini

See CONFIGURATION.md for the full configuration reference.

4. Install and run

sudo make install
sudo dstarrepeaterd /etc/dstarrepeater/dstarrepeater.ini

Build Options

By default, make produces a release build with MQTT enabled and GPIO enabled on ARM (Raspberry Pi). Any option can be overridden on the command line.

Command	Description
make	Default build (release, MQTT on, GPIO auto-detected)
make MQTT=0	Build without MQTT support
make GPIO=0	Build without GPIO support (even on ARM)
make GPIO=1	Force GPIO support on non-ARM platforms
make BUILD=debug	Debug build with symbols and assertions
sudo make install	Install binary, data files, and example config
make clean	Remove build artifacts

Defaults:

Option	Default	Notes
BUILD	release	Optimised, no debug symbols
MQTT	1 (on)	Requires libmosquitto-dev
GPIO	1 on ARM, 0 otherwise	Requires wiringPi; auto-detected via uname -m

Dependencies

Required (Linux)

Package	Ubuntu/Debian	Alpine	Purpose
C++17 compiler	g++ (GCC 13+)	g++	Compilation
GNU Make	make	make	Build system
ALSA dev libraries	libasound2-dev	alsa-lib-dev	Sound card modem support
libusb 1.0 dev	libusb-1.0-0-dev	libusb-dev	USB modem support (GMSK)
Mosquitto dev	libmosquitto-dev	mosquitto-dev	MQTT telemetry (enabled by default)
Linux headers	—	linux-headers	Required on Alpine only

Raspberry Pi (additional)

Package	Install	Purpose
wiringPi	sudo apt-get install wiringpi	GPIO controller support (enabled by default on ARM)

Note: On newer Raspberry Pi OS releases where wiringpi is not in the repositories, install from the unofficial mirror:

git clone https://github.com/WiringPi/WiringPi.git
cd WiringPi && ./build

Disabling optional features

If you don't need MQTT or GPIO support, you can skip those dependencies and disable them at build time:

# Without MQTT (no libmosquitto-dev needed)
make MQTT=0

# Without GPIO on a Pi (no wiringPi needed)
make GPIO=0

# Without both
make MQTT=0 GPIO=0

Windows

The codebase includes #if defined(_WIN32) blocks for Windows compatibility. A Windows build requires:

Dependency	Source	Notes
Visual Studio 2019+ or MinGW-w64	Microsoft / MSYS2	Must support C++17 (/std:c++17 or -std=c++17)
libusb 1.0	libusb.info	Windows binaries available; needed for GMSK modem support
PortAudio	portaudio.com	Required for sound card modem support (replaces ALSA)
Eclipse Mosquitto	mosquitto.org	Optional; only needed for MQTT builds

The provided Makefile targets Linux. For Windows, you will need to create a Visual Studio project or CMakeLists.txt and link against ws2_32.lib (Winsock), portaudio.lib, and libusb-1.0.lib. Serial port, socket, and signal handling code uses Win32 APIs (CreateFile, Winsock2, SetConsoleCtrlHandler) that are included in the Windows SDK — no additional libraries are needed for those.

Note: The K8055 (Velleman) and URI USB controllers are currently Linux-only (they use libusb directly). On Windows they require their respective vendor DLLs, which are not yet integrated.

macOS

Dependency	Source	Notes
Xcode Command Line Tools	xcode-select --install	Provides clang with C++17 support
libusb 1.0	brew install libusb	For GMSK modem support
PortAudio	brew install portaudio	For sound card modem support
Mosquitto	brew install mosquitto	Optional; only for MQTT builds

The Makefile currently targets Linux. A macOS build would need adjusted compiler flags and library paths (e.g. via pkg-config or Homebrew paths). The endian handling and serial port code already support macOS.

Command-Line Usage

dstarrepeaterd <config-file>

The config file path is the only argument. All settings including log directory, verbosity levels, audio paths, and callsign lists are configured in the config file itself.

# Single instance
dstarrepeaterd /etc/dstarrepeater/dstarrepeater.ini

# Multiple instances with separate configs
dstarrepeaterd /etc/dstarrepeater/gb3in.ini
dstarrepeaterd /etc/dstarrepeater/gb7xx.ini

Running as a System Service

A systemd service template is provided in the debian/ directory. The instance name maps to the config filename:

sudo cp debian/dstarrepeaterd.dstarrepeaterd@.service /etc/systemd/system/dstarrepeaterd@.service
sudo systemctl daemon-reload

# Start with /etc/dstarrepeater/gb3in.ini
sudo systemctl enable dstarrepeaterd@gb3in
sudo systemctl start dstarrepeaterd@gb3in

The %i specifier expands to the instance name, so dstarrepeaterd@gb3in runs dstarrepeaterd /etc/dstarrepeater/gb3in.ini.

MQTT Telemetry

When built with make MQTT=1, the daemon can publish live telemetry to an MQTT broker:

• Log messages — timestamped log output
• Repeater status — JSON state updates (1/sec)
• D-Star events — start/end/lost/BER/text in Display-Driver-compatible JSON

See MQTT.md for full details on configuration, topic structure, and JSON format.

Documentation

• CONFIGURATION.md — Full configuration file reference
• MQTT.md — MQTT telemetry setup and topic reference
• BUILD.md — Detailed build instructions
• CHANGELOG.md — Version history

Architecture

DStarRepeater runs as a single process with multiple threads:

• Repeater thread — core D-Star protocol state machine (one of four variants based on operating mode: duplex/simplex, TX-only, RX-only, or TX+RX)
• Modem thread — hardware interface to the radio modem
• Controller thread — hardware I/O for PTT, heartbeat, and external control pins

The repeater thread communicates with a gateway (ircDDBGateway or DStarGateway) via UDP using the DSRP protocol.

Licence

This software is licenced under the GPL v2. See COPYING.txt.

Credits

Originally written by Jonathan Naylor G4KLX. Based on the original DStarRepeater with wxWidgets dependency removed and ported to standalone C++17.