Arduino serialMux host library

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This Python library provides a simple way to create virtual serial interfaces created on an Arduino using the serialMux protocol.

Please see ReadTheDocs for the latest documentation.

Quick start

Plug in the Arduino device and run the serial multiplexer.

$ serial_mux /dev/ttyUSB0
Detected 2 virtual serial ports.
  Virtual serial device 1: /dev/pts/3
  Virtual serial device 2: /dev/pts/10

The virtual serial ports /dev/pts/8 and /dev/pts/9 can now be used to communicate to the virtual serial devices created on the device.

For more information, see the Usage section.

Introduction

This Python library provides a simple way to create virtual serial interfaces created on an Arduino using the serialMux protocol.

For more background information and the reasons that led to this project, see the motivation section of the device library documentation.

This project serves as a reference implementation for clients using the serialMux protocol.

Installation

The software is distributed via PyPI, it can be installed with pip.

pip install arduino-serial-mux

From source

The source is hosted on GitHub, to install the latest development version, use the following commands.

git clone https://github.com/jfjlaros/arduino-serial-mux.git
cd arduino-serial-mux
pip install .

Development

Tests are written in the pytest framework which can be installed with pip.

pip install pytest

To run the automated tests, run py.test in the root of the project folder.

Usage

The command line interface can be used to create virtual serial devices. For more information, use the -h option.

$ serial_mux -h

Initialisation

If the Arduino runs code that makes use of the serialMux protocol, like in this sketch, the serial_mux command will create virtual serial devices.

Start the serial multiplexer on a serial device, e.g., /dev/ttyUSB0.

$ serial_mux /dev/ttyUSB0
Detected 2 virtual serial ports.
  Virtual serial device 1: /dev/pts/8
  Virtual serial device 2: /dev/pts/9

Usage

We can now run the demo program that uses two-way communication over the first virtual serial device.

$ python demo.py /dev/pts/8
received: 0
received: 1
received: 2

Simultaneously, we can look at the log messages that are written to the second virtual serial device.

$ picocom -q /dev/pts/9
System time: 3432
System time: 6860
System time: 10290

Command Line Interface

Arduino serial port multiplexer.

usage: serial_mux [-h] [-o OUTPUT] [-l LOG] [-b BAUDRATE] [-w WAIT] [-v]
                  DEVICE

Positional Arguments

DEVICE

device

Named Arguments

-o

output file

Default: -

-l

log file

-b

baud rate

Default: 9600

-w

time before communication starts

Default: 2

-v

show program’s version number and exit

Copyright (c) Jeroen F.J. Laros <jlaros@fixedpoint.nl>

API documentation

SerialMux

class serial_mux.serial_mux.SerialMux(device, baudrate=9600, wait=2, log=None)

Serial multiplexer.

Parameters

• device (str) – Device name.

• baudrate (int) – Baud rate.

• wait (int) – Time in seconds before communication starts.

• log (Optional[BinaryIO]) – Open writeable handle to a log file.

send(port, data)

Send data from a virtual serial device to the serial device.

Parameters

• port (int) – Virtual serial port.

• data (bytes) – Data.

Return type

None

update()

Receive serial data and send it to the corresponding virtual serial device.

Return type

None

VSerial

class serial_mux.vserial.VSerial(mux, port)

Virtual serial device.

Parameters

• mux (object) – Serial multiplexer.

• port (int) – Virtual serial port.

receive(data)

Receive serial data.

Parameters

data (bytes) – Data.

Return type

None

update()

Send serial data.

Return type

None

Contributors

• Jeroen F.J. Laros <jlaros@fixedpoint.nl> (Original author, maintainer)

Find out who contributed:

git shortlog -s -e