prologix_gpib_async

Python3 AsyncIO Prologix GPIB Driver. This library requires Python asyncio. In contrast to a synchronous implementation, this library makes it possible to control multiple GPIB controllers at once and work with large setups.

The library is fully type-hinted.

Supported Hardware

Tested using Linux, should work for Mac OSX, Windows and any OS with Python support.

Setup

To install the library in a virtual environment (always use venvs with every project):

python3 -m venv env  # virtual environment, optional
source env/bin/activate
pip install prologix-gpib-async

Usage

This library makes use of asynchronous context managers to hide all connection related stuff and also handle cleanup. By the way: Context managers are great!

Initialize the GPIB adapter

from prologix_gpib_async import AsyncPrologixGpibEthernetController

# Create a controller and talk to device address 22
async with AsyncPrologixGpibEthernetController("127.0.0.1", pad=22) as gpib_device:
    # Add your code here
    ...

Sending a "my command" command to address 22 (as set up previously). Do note that strings have to be sent as bytes literals.

await gpib_device.write(b"my command")

Reading data from address 22

data = await gpib_device.read()

Example program, that queries the version string as can be found at examples/example.py

import asyncio

# Devices
from prologix_gpib_async import AsyncPrologixGpibEthernetController


async def main():
    try:
        async with AsyncPrologixGpibEthernetController("127.0.0.1", pad=22) as gpib_device:
            version = await gpib_device.version()
            print("Controller version:", version)
    except (ConnectionError, ConnectionRefusedError):
        print("Could not connect to remote target. Is the device connected?")


asyncio.run(main())

See examples/ for more working examples.

Support for Multiple Devices

The Prologix GPIB adapter supports talking to multiple devices, but there are (theoretical) hardware limits. The Prologix adapters do not have line drivers, so only a limited number of devices can be driven using one controller.

On the software side, there is full support for multiple devices and the driver will switch between different addresses transparently. The driver internally manages the connection and keeps track of the GPIB controller state and manages the state for each gpib object. It is important, that the driver is the only client editing the state of the GPIB controller. Otherwise, the driver state and the controller state may get out of sync.

:warning: Concurrency with multiple devices: Note, that when using a single adapter to control multiple devices, there is no concurrency on the GPIB bus. Whenever reading or writing to a remote device, the driver will lock the GPIB controller to ensure that reading from a controller is synchronous. This means, there is no speed increase, when making asynchronous reads from multiple devices on the bus. Using a GPIB Group Execute Trigger (GET) by invoking the trigger() function, concurrent measurements can be triggered though. Some devices also allow asynchronous function calls, that signal status updates via the srq register.

Example:

import asyncio

# Devices
from prologix_gpib_async import AsyncPrologixGpibEthernetController

ip_address = "127.0.0.1"


async def main():
    """This example will print the IDs of the two different SCPI devices"""
    try:
        async with AsyncPrologixGpibEthernetController(
            ip_address, pad=22
        ) as gpib_device1, AsyncPrologixGpibEthernetController(ip_address, pad=10) as gpib_device2:
            await gpib_device1.write(b"*IDN?")  # Automatically changes address to device 22
            print(await gpib_device1.read())
            await gpib_device2.write(b"*IDN?")  # Automatically changes address to device 10
            print(await gpib_device2.read())
    except (ConnectionError, ConnectionRefusedError):
        print("Could not connect to remote target. Is the device connected?")


asyncio.run(main())

Versioning

I use SemVer for versioning. For the versions available, see the tags on this repository.

Documentation

I use the Numpydoc style for documentation.

Authors

• Patrick Baus - Initial work - PatrickBaus

License

This project is licensed under the GPL v3 license - see the LICENSE file for details