ASYNC PYSERIAL

Python bindings for a C++ serial port library providing asynchronous serial communication support.

Features

• Non-blocking and blocking read/write operations.
• Cross-platform support for Windows, Linux, macOS, and FreeBSD.
• Event-driven architecture for handling data events.
• Support for gevent, eventlet, asyncio, callback, and synchronous operations.
• Uses epoll, iocp, and kqueue for efficient, scalable I/O operations based on the underlying operating system.

Links

• Documentation
• PyPI page

Installation

You can install the async-pyserial package using either poetry or pip.

### Using Poetry

1. Install poetry if you haven't already:

   curl -sSL https://install.python-poetry.org | python3 -

2. Add async-pyserial to your project:

   poetry add async-pyserial

### Using pip

1. Install the package from PyPI:

   pip install async-pyserial

### FreeBSD Installation

For FreeBSD, you need to build the package manually:

1. Clone the repository:

   git clone https://github.com/Lei-k/async-pyserial.git

2. Navigate to the project directory:

   cd async-pyserial

3. Install the dependencies using poetry:

   poetry install

4. Build the package:

   python -m build

5. Install the package:

   pip install dist/*.whl

Usage

Here's a simple example of how to use async-pyserial:

from async_pyserial import SerialPort, SerialPortOptions, SerialPortEvent, SerialPortParity

def on_data(data):
    print(f"Received: {data}")

options = SerialPortOptions()
options.baudrate = 9600
options.bytesize = 8
options.stopbits = 1
options.parity = SerialPortParity.NONE # NONE, ODD, EVEN

serial_port = SerialPort('/dev/ttyUSB0', options)
serial_port.on(SerialPortEvent.ON_DATA, on_data)
serial_port.open()

try:
    while True:
        data_to_send = input("Enter data to send (or 'exit' to quit): ")
        if data_to_send.lower() == 'exit':
            break
        serial_port.write(data_to_send.encode('utf-8'))
finally:
    serial_port.close()

API

### SerialPort A class for serial communication.

#### Methods

• __init__(self, port: str, options: SerialPortOptions): Initializes the serial port with the specified parameters.
• def write(self, data: bytes, callback: Callable | None = None): Writes data to the serial port. Can be blocking or non-blocking. If a callback is provided, the write will be asynchronous. Supports gevent, eventlet, asyncio, callback, and synchronous operations.
• def read(self, bufsize: int = 512, callback: Callable | None = None): Reads data from the serial port. Can be blocking or non-blocking. If a callback is provided, the read will be asynchronous. Supports gevent, eventlet, asyncio, callback, and synchronous operations.
• def open(self): Opens the serial port.
• def close(self): Closes the serial port.
• def on(self, event: SerialPortEvent, callback: Callable[[bytes], None]): Registers a callback for the specified event.
• def emit(self, evt: str, *args, **kwargs): Emits an event, triggering all registered callbacks for that event.
• def remove_all_listeners(self, evt: str): Removes all listeners for the specified event.
• def remove_listener(self, evt: str, listener: Callable): Removes a specific listener for the specified event.
• def off(self, evt: str, listener: Callable): Alias for remove_listener.

### SerialPortOptions A class for specifying serial port options.

#### Attributes

• baudrate: int: The baud rate for the serial port.
• bytesize: int: The number of data bits.
• stopbits: int: The number of stop bits.
• parity: int: The parity checking (0: None, 1: Odd, 2: Even).
• read_timeout: int: The read timeout in milliseconds.
• write_timeout: int: The write timeout in milliseconds.
• read_bufsize: int: The read buffer size. Default is 0. When read_bufsize is 0, the internal buffer is not used, and only data received after the read call will be returned. If read_bufsize is not 0, both buffered and new data will be returned.

### SerialPortEvent An enumeration for serial port events.

• ON_DATA: Event triggered when data is received.

### SerialPortError An exception class for handling serial port errors.

• __init__(self, *args: object): Initializes the SerialPortError with the specified arguments.

### PlatformNotSupported An exception class for handling unsupported platforms.

• __init__(self, *args: object): Initializes the PlatformNotSupported exception with the specified arguments.

### set_async_worker A function for setting the asynchronous worker.

• def set_async_worker(w: str, loop = None): Sets the asynchronous worker to gevent, eventlet, or asyncio. Optionally, an event loop can be provided for asyncio.

Examples

The examples directory contains sample scripts demonstrating how to use async-pyserial for various operations. Below are a few examples to help you get started.

• Basic read and write operations.
• Non-blocking read with asyncio.
• Using gevent and eventlet for asynchronous operations.

Example scripts included in the examples directory:

• interval_write.py: Demonstrates periodic writing to the serial port.
• serialport_read.py: Demonstrates reading from the serial port with different async workers.
• serialport_terminal.py: A terminal interface for interacting with the serial port.

Platform Support

Supports Windows, Linux, macOS, and FreeBSD.

Development

To contribute to the project, follow these steps:

1. Clone the repository:

   git clone https://github.com/Lei-k/async-pyserial.git

2. Navigate to the project directory:

   cd async-pyserial

3. Install the dependencies using poetry:

   poetry install

4. Run the tests:

   poetry run pytest

License

This project is licensed under the MIT License. See the LICENSE file for more details.