bitbangrelay

A simple tool for controlling USB relay boards based around an FTDI FT232R/FT245R chip in bitbang mode, for example SainSmart 4 or 8 channel USB relay modules.

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NOTE: This project is a work in progress, documentation and testing are currently very limited. If this project is useful to you, please let us know how it can be improved.

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Install

There has not yet been a packaged release of bitbangrelay, so the best way to install is via git:

pip install git+https://github.com/SanCloudLtd/bitbangrelay.git

Dependencies

bitbangrelay relies on the following Python modules:

• PyYAML for config file parsing.

• pylibftdi for interacting with FTDI devices.

  • Note that the C library libftdi must be installed separately for pylibftdi to import correctly.

Usage

usage: bitbangrelay [-h] [--version] [-c CONFIG_FILE] [-d DEVICE] channel action

USB BitBang Relay Controller

positional arguments:
  channel               Relay channel to control
  action                Action to perform: 'on', 'off' or 'cycle'

optional arguments:
  -h, --help            show this help message and exit
  --version             show program's version number and exit
  -c CONFIG_FILE, --config-file CONFIG_FILE
                        Config file to load, defaults to ~/.config/bitbangrelay.yml
  -d DEVICE, --device DEVICE
                        Relay device to control, defaults to 'default'

Example usage

• To turn on a channel: bitbangrelay bbe on

• To turn off a channel: bitbangrelay bbe off

• To power cycle a channel: bitbangrelay bbe cycle

  • The connected device will be powered off and then 5 seconds later it will be powered back on.

• To turn off all channels of a relay: bitbangrelay all off

Configuration

The bitbangrelay library parses a configuration file in yaml syntax to determine the available relay devices and channels.

Example configuration:

# Top level keys give names for the available relay devices. A relay device
# named "default" will be the default if no other device name is given.
default:

    # The id is required for each relay device. This is passed to pylibftdi
    # to select the appropriate USB device and is typically the device's
    # serial number.
    id: AAAAAAAA

    # The number of channels supported by the relay device. If this is not
    # provided then it is assumed that 8 channels are available.
    channels: 4

    # Channels can be selected by index or by alias. A dictionary mapping
    # alises to channel numbers may be provided for convenience.
    aliases:
        bbe: 0
        bbe-lite: 1
        beaglebone-black: 2
        raspberrypi4: 3

Maintainers

• Paul Barker ✉️

License

Copyright (c) 2021-2022 SanCloud Ltd.

• Code files are distributed under the Apache 2.0 License.

• Documentation files are distributed under the CC BY 4.0 License.

• Trivial data files are distributed under the CC0 1.0 License.